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Fly Your Radio

Johnny Angel (W4XKE) on December 30, 2007
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Johnny, W4XKE

( Article ) Fly Your Radio

What do model planes have to do with ham radio? Well, for one thing in 1937 twin brothers, Walt Good, W3NPS and Bill Good built the first successful radio controlled model airplane. Radio and modeling have been married ever since.

(Photo - Walt & Bill Good 1937)

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(Photo - Walt & Bill Good 2000)

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My introduction to radio and modeling occurred in the early 1950s. Many a boy has learned the value of a dollar at the model shop. My friends and I used to search the roadsides for pop bottles that we could redeem at the local grocery store for a 2 cent deposit. Fifty pop bottles would buy one 98 cent model kit and 2 Tootsie Roll Pops. Ever try to ride a bike while carrying a burlap bag of 50 bottles? 0x01 graphic

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Here's a photo of the bicycle / model shop where much of my time and money was spent. The shop owner was everybody's “Grandpa Charlie” who promoted the model Texaco fly ins and he would talk airplanes with us kids as long as we had time to kill. We all knew every item he had in the glass case and how many pop bottles it would take to buy them.

Over the years I built scale, free flight and U-control model planes. Eventually I got into RC with a Babcock radio (that used a single vacuum tube) that provided rudder only control with a Bonner rubber band escapement. The guys that had good jobs were spending big money on “full house” RC planes using reeds. Up was full up and left was full left. Proportional control didn't come out for several more years.

One plane that I really flew the pants off of was a Carl Goldberg Skylane 62 with a K&B .45 and a Kraft radio. Oh the stories I can tell about flying that plane! Let me warn you, once you've built and flown a model, the blue sky is incomplete without an airplane in it.

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Modeling Memories Last a Lifetime

I'd like to tell you about one of my all-time favorite planes. It's a marvelous little airplane that is worthy of some discussion. Sometimes in our efforts to strive for the ultimate model, we burden ourselves with expensive equipment, complex, time-consuming designs and many extra hours at the bench. For the most enjoyment, I say we need to go back to the basic model that is cheap, simple and easy to build.
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Here is Ken Willard's Top Dawg. It's easy, quick to build and depending on your preferences, can be very inexpensive for an RC model. Roger Hite was the first person I saw flying one of these. I had my Skylane 62 out at the old concrete Navy field and others there were flying their pattern ships. There was a Bridi Super Kaos, a Banshee, a Kwik Fly III and other high end (expensive) models.

Roger brought out his little Top Dawg with a single channel, rudder-only control and a Babe Bee .049 engine. I watched as he peaked the little Cox until it was shrilly screaming. He checked his rudder and let it go.

I was curious what would happen when it became airborne. He couldn't reduce the engine's power and all the control he had was left and right. There was no need for me to worry. The Dawg screamed away from us with the tail high and quickly left the concrete. Upon liftoff, Roger gave it a touch of rudder and began a climbing right spiral. He continued the upward spiral until he had gained some altitude, then let it go straight. At full throttle it began to steepen the climb until it finally stalled, dropped the nose and went into a power dive. I thought it was a goner because he had no elevator to pull out.

The Dawg screamed straight down toward the ground. As the speed increased, the Dawg's flat bottom wing developed more and more lift as the nose came up into an inside loop. Roger topped the loop and came down the backside into another power dive. This time as the Dawg leveled out at the bottom and started up once more, he pushed hard rudder and had two quick snap rolls. Afterward, he rolled into another climbing spiral and circled the field. I couldn't believe the performance of this ship with a single channel control!

Roger continued to frolic in the sky until the little engine screamed into a frenzied peak and went silent. He eased the Dawg into a gentle descending spiral, lined it up for a landing and let it go straight. It glided perfectly into a dead stick landing that left us in awe. I looked around and all the guys with the big pattern ships, their kids and even the wives were affixed on the performance of Roger's little airplane.

If allowed to climb, it'll stall and go right into a power dive, followed by a loop. To control the climb, just feed it some rudder and let it circle. Tighten the circle and the nose will drop. Ease out of the turn and the nose will rise. Let the speed build and hit a hard rudder and you have some quick snap rolls. Trim the ship for a nice power off glide and it will land itself. Roger made us feel foolish for having spent so much money. We could have built a dozen of these for the money we'd invested in our planes. To top it off, he seemed to be having a lot more fun! We had big field boxes with fuel pumps, electric starters and gallon-sized fuel cans. Roger had a battery, a pint squirt-can of glow fuel, a chicken stick and a rag hanging from his hip pocket.

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A Fine Example of A TOP DAWG (cheek cowls can be added for extra cooling)


Of course you still have the option to mount a .15 or a .19 up front and hinge the other control surfaces for a 3-axis radio. The flat bottom wing could be changed to a symmetrical foil to keep it straight at all speeds. There are plenty of designs that already do that however. The original ship's flat bottom wing, the simplicity of construction, and the incredibly low cost is where the Top Dawg really shines! You can't get more bang for the buck.

As an FCC licensed radio amateur, you are qualified to operate a radio control system on the 6 Meter band. If you haven't explored your ham privileges in modeling, you may be missing much of the fun. It's never too late and remember, “Model Building Builds Model Boys” (Even older boys.)

Footage of Walt and Bill Good:

http://www.youtube.com/watch?v=2kEGUgSoJm0

Johnny, W4XKE

Member Comments:
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Fly Your Radio  
by KG4RUL on December 30, 2007 Mail this to a friend!
My favorite RC model aircraft was a Cleveland Condor glider kit (72" WS) that I built up. It had a two tube receiver, single channel in it that used the little "peanut" tubes. The rudder was controlled by a rubber band powered escapement. It had 4 states: rudder centered, full right rudder, rudder centered, full left rudder, which it cycled through until the rubber band was unwound.
 
RE: Fly Your Radio  
by N6HPX on December 30, 2007 Mail this to a friend!
seen some of these planes up in Kitsap Washington when I came there by ship.Nice models and wanted one but the sea bag has its limits.
 
RE: Fly Your Radio  
by KF4HR on December 30, 2007 Mail this to a friend!
Great article Johnny! I've been in the RC hobby since the early 70's. It was interesting reading about models I had flown or seen before. RC is a great past time and a great way to blend two hobbies, especially when you add some ATV gear and a camera in the model! Over the last 10 years or so RC has really started to take off (so to speak); with real jet engines, 50% scale models, computerized RC radio's, and numerous other innovations. There's no telling where it'll go from here!
 
Fly Your Radio  
by KB2DHG on December 30, 2007 Mail this to a friend!
What a wonderful nastalgic journey!
AHHH those were the days! HOBBIES yes HOBBIES no matter what they were, it was just great fun. I was into slot car racing and did some R/C flying too. What happend to these kids of today? I love, to this day building modles and having hobbies! I cant imagine my life without them?
I don't want to get inot a negative feeling of our youth of today but I rarely see kids today building modles, coming into Ham Radio or even playing outside stick ball and the simple games we played.

Well, Thank you for this stroll back to a much better time!
DE: KB2DHG
 
RE: Fly Your Radio  
by N4CQR on December 30, 2007 Mail this to a friend!
Excellent piece.
 
RE: Fly Your Radio  
by W5GNB on December 30, 2007 Mail this to a friend!
I really enjoyed your writeup Johnny. I have been in R/C since I was a kid and started out with the old single channel radio stuff, I believe it was a Heathkit if my memory serves me right. As a kid, I got all the "hand-me-downs" from the older guys and amazingly I made most of it fly and operate with little trouble.

I have several R/C systems operating on Six meters and 2.4Ghz now so in a way, I am operating Ham radio while at the field.

I now have the BEST of equipment and High Resolution video transmitters on board and the works, But I still have a few of the old simple models around to have fun with.

73's and we will see you on CW and hopefully at one of the R/C airplane meets one day.

Gary - W5GNB
 
Fly Your Radio  
by K1CJS on December 30, 2007 Mail this to a friend!
Nice article! Although it is mostly about modeling and flying--not ham radio, it is a refreshing change from the pieces that usually are printed here. Thanks!
 
Fly Your Radio  
by KC9MAV on December 30, 2007 Mail this to a friend!
Very intersting when I go to the local field (palos rc flying club) all the ham frequencys haven't been taeken but know sadely spektum has made a radio that has it's own frequency. Benifits the flyers maybe some people will see the ham frequencys and they will get a license. I love to fly my GWS stick and my dad's mini telemaster along with his sailplane. Currently though my hobby is ham radio.
 
Fly Your Radio  
by K3UD on December 30, 2007 Mail this to a friend!
Great Topic!

I started out at about 1957 at age 6 with slip together chuck gliders usually Comet, Testor's, and most of all, Jim Walker's American Junior designs like the catapult launched Interceptor and the rubber powered AJ Hornet. I lived within 3 blocks of a municipal park where modelers flew
U control and I knew that I wanted to do what they were doing. It was in 1959 when my cousin George gifted me with a well used Jim Walker Firebaby.

It came with a Wen Mac .049 engine and a spare OK Cub .049, some fuel and a starter battery with alligator clips that attached to the top of the glow plug and the engine mount. I was thrilled to get it. My father took it out to the patio and showed me how to fuel and start the engine. With the help of an older kid in the neighborhood I began to learn how to fly U control. The Firebaby was just what I needed to learn with.

Eventually the Firebaby ended up in a crash while I was attempting inverted flight. I started to buy the COX, Wen Mac, Aurora, and Comet ready to fly models. While they all flew OK and looked great they did not perform as well as the old Firebaby did. In the end I started to build U control models from balsa kits by Scientific, Berkley, Top Flight, Sterling and Goldberg. I think I liked the Goldberg designs the best.

In the early 60s I got my first taste of radio controlled flight when my father took me to Willow Grove Naval Air Station just outside of Philadelphia. It seemed that there was a model aviation contest going on there. I had no idea that this was the AMA Nationals. I could not believe how well those models flew, especially the radio controlled models. My father got some information about radio control in the local area and found that there was an RC flying field at Valley Forge. We went out there on several consecutive Saturdays and got close up with those who were flying.

This led to my first RC model kit. It was a Sterling Mini Mambo. I built the kit and then purchased a Controlair 5 RC regen receiver kit, A Bonner escapement and a Kraft transmitter, The torque for the escapement came from a wound rubber band. This was single channel rudder only control but it was more like free flight than anything else. It did fly though.

A bit later I upgraded to a Goldberg Falcon 56 and a Controlaire Galloping Ghost radio system. This gave me 3 channels of control, rudder, elevator and Engine. For those who never saw a Galloping Ghost system ( of Glitchy Ghost), it worked by keeping the rudder and elevator flapping during the flight. Setting it up and keeping it in sync was a bear.

I had purchased an Enya .09 RC engine for the Falcon as it was all I could afford at the time. In retrospect, I wonder why Goldberg ever recommended an .09 for the Falcon 56. In my case, hand launches were the order of the day and while it flew it was never very satisfying. One of the guys at the flying field gave me a .19 engine it it added the needed power for runway takeoffs and some lazy aerobatics.

I was very active in RC up to about 2002 and have flown Pattern, Quickie 500, Sailplane duration and usually I was the instructor for the clubs I belonged to over the years. Maybe someday I will get back into it.

I mentioned American Junior. Many of Jim Waker's designs are back in production. I have a new Interceptor and AJ Hornet. For those who might be interested here is the URL.

http://www.americanjuniorclassics.com/

73
George
K3UD
 
RE: Fly Your Radio  
by WI7B on December 30, 2007 Mail this to a friend!

Johnny K4XKE,

Really enjoyed reading this article! I used to fly a small model with a Cox .049 engine as a kid. There are so many different avenues for hams to explore in R/C (e.g. model sailing, cars, rocketry). But watching your own 'bird' take off and soar is right up their in terms of fun.

73,

---* Ken
 
RE: Fly Your Radio  
by W6TH on December 30, 2007 Mail this to a friend!
.

Flying Your Radio, mine was a little different as it consisted of the B1-B Bomber and the Space shuttle.

I flew models many years ago and was a fun project. May give it another try when it warms up a bit. How about the Kite hobby as well?

Thanks for a nice read, a change of pace sure is needed and ham radio is not the only enjoyable hobby.

73, W6TH.

.:
 
RE: Fly Your Radio  
by KL7IPV on December 30, 2007 Mail this to a friend!
My first plane was a red 1/2A Wen Mac plastic model that a neighbor kid said he could help me with. He took the control lines and quickly augered the model into the ground ruining the plastic. I never got to fly it. My brother had gotten a Wen Mac plastic 1/2A car that ran in tethered circles. He had more fun with that than I got to have with the plane. But I didn't give up. I then built my own control line model, a 1/2A flying wing. I was too young to buy the fuel so I spun it in circles and it flew reasonably well. Then I went to a galloping Ghost in 1963 and it has been uphill from there. Built a Heathkit GD-19 on 50Mhz (ham radio finally!), bought a MRC 5 channel for me and and a Kraft brick 2 channel for my wife. I now use a 1986 Circus Circus JR single stick 7 channel on 50Mhz. I am not going to replace the module with a 2.4GHz spread spectrum unit. I have gone from CL to RC power semi scale warbirds to soaring. Less mess, a lot quieter and if I hit something, less mess!
73,
Frank
 
RE: Fly Your Radio  
by WY3X on December 30, 2007 Mail this to a friend!
I still sport scars where a prop got me 5 times across my right pinky finger before I could get my hand away from the plane! I wasn't meant to be an r/c pilot. I have an electric jobbie now, but it has nowhere near enough power.

I think it would be an interesting project to send up a beacon CW transmitter in an r/c plane to see how far it could be heard. Anyone have a website with kits of this type for sale?

Thanks, -KR4WM
 
Fly Your Radio  
by KB9RQZ on December 30, 2007 Mail this to a friend!
well you did over look the other ways in Hamradio intragrates to RC

PersonalyI tend to run the comon 75 mhz Or was 78 I look it up when I need to to know) but I put my smalest FS ATV gear allows me to go flying wihthout leaving the ground and suffering the effects of that

not to mention that a smal APRS package has helped recover my aricraft (put one on the my second traner after the first one kinda "escaped" I still have the second trainer aircraft for some reason
 
Fly Your Radio  
by KB9RQZ on December 30, 2007 Mail this to a friend!
well you did over look the other ways in Hamradio intragrates to RC

PersonalyI tend to run the comon 75 mhz Or was 78 I look it up when I need to to know) but I put my smalest FS ATV gear allows me to go flying wihthout leaving the ground and suffering the effects of that

not to mention that a smal APRS package has helped recover my aricraft (put one on the my second traner after the first one kinda "escaped" I still have the second trainer aircraft for some reason
 
RE: Fly Your Radio  
by KI4HVT on December 30, 2007 Mail this to a friend!
One of the main reasons I took my technician's test was so that I could fly on 50Mhz sinnce 72Mhz was always crowded. Since then, I have used APRS so that I can track my flights with a moving map display on my laptop. Additionally, I have used 2.4Ghz wireless video to record my flights. Great article!

http://www.bijouxdesigns.com/video/osdgps2sml.wmv

http://www.bijouxdesigns.com/video/night%20flight_final.wmv

-dave
 
Fly Your Radio  
by N0PSH on December 30, 2007 Mail this to a friend!
Great article. I too fly R/C. Still have an ACE single stick on 52megs. Started out on C/L as a kid then graduated to R/C and haven't looked back since. Didn't fly this past summer (busy schedule) but you sure struck a cord with me and will be flying this summer. Come on out to the midwest and fly with us.
TNX for the article.
de AL kc0mce
 
RE: Fly Your Radio  
by KF4KQI on December 30, 2007 Mail this to a friend!
It has always amazed me how many hams are into RC flying.
It comes up many times in my QSO's when I first meet someone on the bands.

 
Fly Your Radio  
by N0AH on December 30, 2007 Mail this to a friend!
best eHam article ever-
 
RE: Fly Your Radio  
by N7YA on December 30, 2007 Mail this to a friend!
My sons CAP meetings are held on Nellis AFB, so many of the CAP senior members are active military already at work, many of them are into RC modeling.

I agree, its a great hobby. At one of the meetings, the flight instructor decided instead of ground school paperwork, he would show the kids some videos and slides...one was of a HUGE RC model of a B-52...with 8 fully functional jet engines. This thing was the size of a piper cub, no lie! And it flew...the builder should have a contract with the military. A lot of the kids perked right up when the video of the jet models was shown, and when the picture of the B-52 popped up, i gave a very audible and youthful "COOL"...dads arent supposed to do that! hihi...couldnt help it. Look it up online, amazing build.

This is a great thread, shows that our interests are varied. I used to do model rocketry as a kid, i also liked to buy a bunch of those balsa wood wind up planes at the hobby store and make one big multi-engined rubber band powered mostrosity (sometimes i got lucky and it flew). One day, when i was 12, my dad worked on Elmendorf AFB in Alaska in the old inbound terminal right next to base operations. All the officers and enlisted personel got used to seeing me hanging out all the time and flying my planes. many of the pilots would come in and hang out with me, one P3 crew even took my plane when i was away and was out on the tarmac flying it off the wing of their aircraft. I really loved everything about flying...so much so that a colonel (who i later found out was my teachers husband, go figure) brought me back into base ops and showed me how it all worked, then took me with him to clear the main runway of FOD. All because of an interest in aviation. RC modeling is a great introduction to flying for many kids and adults alike that could lead to greater things. Nice article.

73...Adam, N7YA
 
RE: Fly Your Radio  
by W9OY on December 30, 2007 Mail this to a friend!
You flew the space shuttle? WOW
 
RE: Fly Your Radio  
by W6TH on December 30, 2007 Mail this to a friend!
.
The radio flew, not me.

.:
 
Who wants to start a NET or a ROUNDTABLE?  
by W4XKE on December 30, 2007 Mail this to a friend!
Gee whiz, I didn’t know there was such a swell bunch of experienced modelers in our midst. By the way George, thanks for posting the link to Jim Walker’s page in your comment. Jim was definitely one of the ‘greats’ of the day. I wish I’d had opportunity to meet him. I’d like to encourage each one of us to look at this web site and to click on each link that is provided on the site. It is very, very interesting reading for us boys!

Let me also offer these additional 3 links that tell a video story of a model airplane meet of long ago. It provides some more wonderful nostalgia:

Plymouth Dealer’s 1947 Model Contest:

Part 1 http://www.youtube.com/watch?v=mTssIzyi5kA&NR=1
Part 2 http://www.youtube.com/watch?v=Q0sgIYdubrI&NR=1
Part 3 http://www.youtube.com/watch?v=q2udiOCnsgA&NR=1

We’ve already heard from some wonderfully unique hams that have accomplished incredible things. It just goes to show, you never know who might answer your CQ! A rocket scientist; An electrical broadcast systems engineer; A rocket driver! WOWSERS! Others like myself have taken their modeling a step further and have been flying the real thing as private pilots. There are a lot of avenues of interest represented among us. Maybe we’ll stir the interest of some youngsters of the Twenty-First Century?

I’ve already had several emails from hams who are interested in setting up a Net or Roundtable for those of us who like to compare notes on modeling. (Oh NO! Not another net on 40 meters? HI HI )

Right now I only have an antenna up for 40 Meters (and spent the day outside working on it with my neighbor, Tom, K4TCH but it still has problems.) Flat SWR but apparent RF feedback problems that drives computer equipment nuts.

I can schedule a time on my EchoLINK node # 215860 or go to an IRLP reflector such as 9255 where we can meet. Whatever’s your cup of tea; (HF 40, EchoLINK or IRLP)

Soon I’ll have capabilities of some other bands so anything is possible and suggestions are sought. This would be a good time of year to kick off an new idea… January 1, 2008.

Johnny, W4XKE
 
RE: Fly Your Radio  
by N6HPX on December 30, 2007 Mail this to a friend!
I wanted to get into the airplanes but didnt have an area to fly em, spent all my time with model railroads and slot cars myself, but was also a snake and lizard lover.
'
 
RE: Fly Your Radio  
by UC1AWX on December 30, 2007 Mail this to a friend!
by W6TH on December 30, 2007

Flying Your Radio, mine was a little different as it consisted of the B1-B Bomber and the Space shuttle.

I flew models many years ago and was a fun project. May give it another try when it warms up a bit. How about the Kite hobby as well?
--------------------------------
Triple shot here! Kite in the sky on Looong Wire makes good launch platform for RC Glider :)
 
Fly Your Radio  
by W4XKE on December 31, 2007 Mail this to a friend!
I belonged to the Converse R/C Club. We were fortunate to live near a huge octagonal airstrip that was built for the US Navy carrier trainers for WWII at Converse, IN. There was never the problem of a crosswind unless you wanted to deliberately take off in that direction. The navy had decommissioned the place and leased it to the city of Converse for their municipal airport and the city commissioner allowed us to fly there.

Actually, several clubs and individuals from Marion, Peru, Sweetser, Oak Hill, and Wabash frequented there because it was such an ideal place to fly. (Concrete as far as the eye could see, out in the middle of hundreds of acres of farm land.) There was often a crow that you could chase with your model plane.

Being a military field, they didn't allow any buildings or structures like a toilet, a trash barrel or a sun shade. The city commissioner would often come out and inspect the area where we were flying and scold us if he found any pieces of wood or rubber bands laying on the ground. Sometimes, midnight lovers would go out there and throw trash (beer bottles, clothing articles, etc.) and so we would have to police up the whole area before we began flying so we weren't blamed for the debris. (I'm sure the commissioner knew we weren't responsible for a lot of the trash but he knew he had a free clean-up team if he threatened to restrict us from the site if we didn't keep it tidy.)

The only bad thing about flying from concrete is when you really dork one in, there’s nothing but the tail feathers and some fragments left. When MonoCote came onto the market it made our cleanup much easier. There would be a colorful plastic baggie full of balsa particles left out on the field to pick up in one stroke.
 
RE: Fly Your Radio  
by W0FM on December 31, 2007 Mail this to a friend!
Hi Johnny,

My first RC aircraft in 1968 was also the Goldberg Skylane 62. I built the Heathkit 4 channel RC transmitter, receiver and four servos and flew the Skylane for sometime after that. (52 MHz)

About three years later my son and I restored the old Cessna and still fly it today.

Happy Landings!

Terry, WŘFM
 
Fly Your Radio  
by KD5SFK on December 31, 2007 Mail this to a friend!
Very cool R/C model airplane article, but I'd like to know more about the "radio" side of the hobby!
 
Fly Your Radio  
by KE4ZHN on December 31, 2007 Mail this to a friend!
Great article. Ive been into RC off and on for the past 23 yrs. Tried everything from RC cars to boats to even motorcycles! Gas powered RC motorcycles are kind of rare in the US and very challenging to control. No gyros or special balancing is used. Just keep it moving at speed and it will self balance. Turning is another matter and takes time to master. I had 8 boats at one time in all classes. Including one of the first weed whacker powered models. And yes, of course planes too. The only thing I havent tried to master is RC helicopters. Im currently down to one RC bird and havent flown in some time. I think its time to dust off my Ultastick 40 and run some nitro through it.
 
RE: Fly Your Radio  
by KG6WLS on December 31, 2007 Mail this to a friend!
"You flew the space shuttle? WOW"

RE:

"The radio flew, not me".


And so did a few tiles.
 
RE: Fly Your Radio  
by KG6WLS on December 31, 2007 Mail this to a friend!
"I wanted to get into the airplanes but didnt have an area to fly em, spent all my time with model railroads and slot cars myself..."

Hey, Larry. You and I DO have something in common after all!

When I had the room, I was a model railroader myself and ran the H.O. scale. It wasn't radio but, it did involve some solder smoke from time to time. Still have the steamers, engines, cars, etc. packed neatly away for the next time. Good scale to work with. Not too big, and not to small. Every now and then I visit the model railroad museum at Balboa Park in San Diego. It's still growing with more track and landscape each time I visit there.

73
 
Fly Your Radio  
by N0AH on December 31, 2007 Mail this to a friend!
I always find it amusing to read postings that claim the current article is nice to read but too bad it does have a whole lot to do with amateur radio.

I think these folks should get out their ARRL operating manuals and read-

Robotics-
Model Planes-
Satellites-
Farm Equipment-
sink proof radio controlled boats built for floods-

etc......
 
RE: Fly Your Radio  
by KF4A on December 31, 2007 Mail this to a friend!
Great article Johnny. Brings back a lot of memories of past times.

Donnie - kf4is
AMA 39099
 
The Electrical Side of Radio Control  
by W4XKE on December 31, 2007 Mail this to a friend!
KD5SFK wrote: "Very cool R/C model airplane article, but I'd like to know more about the "radio" side of the hobby!"

So KD5SFK, this is for you and others who have an interest in the radios. (Some flyers like to build, some like to machine the engines and others like to design the electronics.)

Information provided by Jaymen, Some Digital-Proportional History, R/C Universe

Walt Good developed the first pulse systems for model radio control that were proportional. This system, called TTPW(Twin Tone, Pulse Width modulated) was a bit tricky. It used a motor like a Mighty Midget with spring or rubber bands to center it, driving a toque rod, or string linkages to the control surfaces. The end result was that the rudder and elevator flapped equally in each direction at neutral. The plane would ignore the flapping and fly straight. When the joystick on the control box was moved, the rudder, and/or elevator would flap in one direction more than the other, and the plane would respond accordingly. You could get a measure, or a proportion of control relative to the amount of joystick movement. When it worked, it was far superior to escapement, or multi channel because you had infinite control, and trim on both functions.

The transmitter was an old tone rig, ground based, but with a new control box attached in place of a push button handle/key. The control box had a joystick, and the early ones used a motor and cam to trip switches, thereby pulsing the two-tone generators on and off in the transmitter. The joystick controlled the motor speed which controlled the pulse.... crude, but effective. In the receiver, relays were used to switch power, as transistors were not around yet, it was all tube. G-forces generated by hard maneuvers could easily "pin" the relay arm closed, resulting in a loss of control, so modelers quickly learned to mount the relays vertically in the plane. This was also done later with reed banks.

The terms "kicking duck", and Mickey Mouse were applied to these early proportional systems, because they were a bit flaky if everything was not "just so" and the elevator rate at full up was slow enough that the plane followed it in a jerking/kicking motion. Galloping Ghost came from the same phenomena of the plane following the surfaces at certain stick positions, like a ghost had control of it. These systems were extremely popular back on the east coast, and eventually in the mid-west.

Dr. Good, Maynard Hill, MacEntee, and even Zel Ritchie all had their own versions of this system, many built their own, and all were hand built at first. Multi-channel tone came in because it was relatively simple to set up. You could get a ready made matching transmitter and receiver, then all one had to do was wire up the servos and battery packs. Linkages were much more straight forward that with pulse systems too. Moreover, you could get a full 4 functions(Rud,Elev, Throt, Ail) whereas with Pulse/TTPW, you only had two functions, no throttle. This made reeds and multi the choice for precision aerobatics.

Out west, if you flew pulse or TTPW, they poked a lot of fun at you and made jokes about the "flapping" If you didn't fly reeds, Orbit in particular, you were in the stone age and not "with it". Flying a single channel with a Vari-Comp was more respectable than "flapping", even if it was Proportional. Most of the major manufacturers had committed their production and designs to multi-channel reed systems, it was the "premier" system and considered state of the art. The pulsed proportional guys were considered on the fringe and not regarded as mainstream, they were the oddballs. Reeds reached such a high state of development at that time(1961) with the advent of the Bonner Transmite, the Deans reed bank, the Orbit 10 channel superhet that other systems could not begin to compare with them. Even if you had a transistorized TTPW, you still had a home-brew set-up. The first analog proportional systems like the Ulti-Multi were also viewed with skepticism, and besides, they were not available for sale. No, if you wanted to fly aerobatic pattern, and didn't have an electrical engineering degree, you flew multi-reeds. Pulse was kind of forgotten about for the time being.

Along in the mid 1960's some guys back east came up with some more sophisticated versions of TTPW, and someone got the wise idea to eliminate one tone and in it's place add rate/ frequency shifting to the remaining tone, giving you two functions from the rate and pulse width shifts of a single tone. This, coupled with the advent of the solid-state superhet tone receivers, which were inexpensive basic single channel rigs, and the availability of lightweight European actuators and motors like the Micro-Mo, and Bella-matic made pulse proportional a bit more practical. But you still had to come up with a pulser. Cannon, Ace, and others offered pulser boxes to convert your single channel tone transmitter to pulse. In these systems, you typically had proportional rudder, and positionable throttle. Some used tone off and a Pulse Omission Detector(POD) in the receiver for throttle commands. Others cycled high or low with full tone on, or off respectively. The more advanced set-ups required you to build your own joystick and modify the pulser for rate control to get elevator...it was still a tinker's world. It was around this time that the term Galloping Ghost was coined.

By 1965, the Bonner Digimite was out, and the significance was that many could now obtain the Bonner 2-axis stick for use in a homebrew pulser box. This quickly led to many R/C manufacturers offering their own versions of pulse proportional. Strangely, the leader in this renaissance of pulse was Min-X, and they used their own stick, which was superior. The rest, like Controlaire, F&M, Hallco, and others all came out in quick succession with 3 function pulse proportional rigs. Later, companies like Bonitron, and EK had refined versions of Ghost, EK called theirs a "Digi-Ghost"! The last rage was dual actuator at high rate; it gave almost interaction free control at the cost of eating AA pen cells like popcorn!

By 1972 the Galloping Ghost fad was over, it lasted only 5 years, but in that time it afforded a relatively reliable and cheap alternative to full-house multi, and proportional, it was a gap filler. By 1969, digital proportional had become fairly reliable, and a few years later the prices finally dropped below $300.00 so it took over even the entry-level radio market.

Looking back at the surviving vanguards of the first modern digital radios of the early sixties, there was considerable competition in development and manufacturing.

After the Spreng/Mathis Digicon debacle, Frank Hoover introduced his F&M Digital 5. Frank had reversed the modulation scheme to keep the RF carrier on during the sync pause, providing a more continuous RF link from Tx to Rx, and more importantly this stabilized the output of the receiver's AGC circuit which improved glitch resistance significantly.

In the meantime, established names like Space Control, Bee Dee, and Sampey were still considered more reliable. Even though Hoover had the digital market to himself, he was still attempting to perfect the servo feedback system and this led to several different servos of different manufacture being offered.

Around this time, Zel handed over Space Control to the Dunhams and went to work for them. It seems his accountant had swindled his bank accounts dry while he was away on a trip to Chicago! Zel tried to continue on for a while after a move to Sylmar(cheaper rent) but the deathblow had already been dealt, so he became an Orbit employee.


Bill Cannon though his association with Doug Spreng subsequently came out with the Digicon II, which incorporated all the updates to the original Digicon, including the afore mentioned revised modulation scheme.

At this time everyone jumped in at once, but proportional was very expensive due to the high count of germanium and silicon diode and transistor semiconductors required, and the 2 axis joystick assemblies. Howard Bonner, Phil Kraft, the Dunhamms(Orbit), WS Deans, Min-X, EK, and Citizen-Ship all came out with digital radios within a year of each other. There were many changes in versions of each make. For a while, open gimbals were popular, but then almost everyone used the Bonner stick, as it was cheap. Finally everyone came up with there own closed gimbal, and here the Kraft became an industry standard used by many other later on.

Digressing to Howard Bonner. How did an escapement and multi servo manufacturer leap frog the whole single channel, then multi-tone reed, and later analog proportional radios and suddenly release the Digimite with no previous radio system manufacturing experience?
Well, Howy hired a couple characters named Bob Eliot and Gerry Krause to design the Digimite. The system is interesting in that it still used an analog voltage feedback servo, thus it was slow and lacked torque coming off neutral when compared to a pulse comparator type servo. Almost instantly, E&K left Bonner to form EK Logictrol, where they perfected a true pulse comparator type servo amplifier.

By 1966 everyone was in the market, as nobody made any effort to protect their intellectual knowledge, but rather they freely shared it. As such, only a few came out on top in the end, and Phil Kraft was the one guy who really made it into a moneymaker. He got Cliffy from Bonner, Jerry Pullen from JPL, Chuck Hayes (Dick Railing's right hand man at Orbit), Joe Martin from Micro Avionics, and many others together under one roof, thus assembling a huge talent pool that specialized in R/C, it truly was a golden age. Ironically the radios produced by that group where the Gold Medal Series, so named for the numerous national and world championships Kraft radios had won.

Howard Bonner sold out early to Gordon Larson, having been sued by Sperry over the harmonic drive he used in the later 4RS servos, he wanted out. The Dunhams also sold out to Datatron, and Micro was pulled back in house after that because the they had reliability issues. This left Novak, Spreng, and Mathis free to find other pursuits. Novak wound up with Larson and RS Systems, which he eventually inherited form Gordon. Doug went off to England and developed some propo radios there. Mathis and Dunham continued to drink at the bar over in Garden Grove! Hoover was trying to recover from his Magnavac servo fiasco and in the meantime Kraft had created PCS, and was selling radios to HeathKit. Joe Fossgate left EK, and went on to form Pro-line, but that was a bit later. EK had moved to Texas and was contemplating making radios in Mexico, which they ultimately did, remember the LRBs?

As one can see, everyone in the industry moved around quite a bit before the dust really settled, so prolific where those days of the early transistor era. It was a time when technology made great leaps in terms of miniaturization due to the post war introduction of the transistor, and other semi-conductors such as the IC. The designs existed, but where large and crude because they used tube and relay technology. The rage was to take and create a solid-state versions of these designs, which made them much smaller, more reliable, and simpler....but not cheaper, well not at first!

The biggest problem beyond the servo, which was licked first, was the decoder in the receiver. Many of the SCS(silicon controlled switches) type decoders tended to latch up and quit working, or shift channels. JK flip-flops had issues as well. When the first good TTL counter chips came out like the 74SN174, decoders became reliable. The introduction of ICs to R/C propo came in the Bonner Digimite receiver, they were flat pack surface mount and years ahead of their time, but suffered the problems mentioned above. Thus, the Bonner was quickly surpassed as everyone was making improvements to their systems as newer devices became available.

So digital had several false starts at the beginning of the sixties, and it took about four years for it to become a mature technology. In ten short years, many companies came and went, many of the key players being the same behind the scenes.
 
RE: The Electrical Side of Radio Control  
by VA7HYD on December 31, 2007 Mail this to a friend!
Cool article... thanks!

Oddly enough RC airplanes are what got me into Amateur Radio... ... I spent a few hundred hours out over the North Atlantic looking for "big grey things with Russian accents".

Several years ago I started flying RC airplanes... and a couple of years ago, a couple of us crashed for no apparent reason.

A hand held scanner sweeping the 72MHz band revealed the presence of a 72MHz signal unrelated to the transmitters in use at our flying field. I knew how to DF a signal. I knew how to "fix" the position of an emitter by obtaining a couple of bearing lines. I knew that it was possible to make a directional antenna... but I didn't know how to construct such an antenna.

Help from a "ham" had me making a small loop antenna and a Yagi for 72MHz... we never did prove who was turning on a transmitter to "shoot down" our airplanes.... but a couple of subtle "threats" later and the problem went away...

...and thanks to the help I got from a ham, I have my own "ticket" and am invlolved with a local ARES group.

...funny how my airplanes led me to a second expensive hobby...
 
Fly Your Radio  
by K6YE on January 1, 2008 Mail this to a friend!
Johnny,

Congrats on a great article. I always enjoyed watching RC planes and helicopters in Van Nuys, California. In addition, on behalf of the San Fernando Valley Amateur Radio Club, I invited two hams to give talks and demo their wares on a regular basis. I was always amazed at the physical construction, flying skill, electronics, displayed.

I never pursued this aspect as I was already engrossed in DXing. This is another one of the many facets available in our great hobby. Have fun.

Semper Fi,

Tommy - K6YE
DX IS
 
This is SWELL ... even for a HAM!  
by W4XKE on January 1, 2008 Mail this to a friend!
Dave, KI4HVT posted these two links and I’m going to post them here again just in case somebody missed them:

http://www.bijouxdesigns.com/video/osdgps2sml.wmv

http://www.bijouxdesigns.com/video/night%20flight_final.wmv

The narrator of the 1940s video clip asked where the bright young minds of modelers would eventually go. I believe those kids in that old black & white film would be very surprised and much impressed with Dave’s videos. (We’ve come a LONG way, baby!)

I’ll bet a lot of modelers besides me have dreamed of having airborne video. As a matter of fact, Buford Gross of Peru, IN once mounted a Brownie 8mm camera on top of his wing with rubber bands. All went well with the flight until he pulled up into a stall/spin when he discovered the big camera disrupted his ability to recover from the spin. We were all invited to a special club meeting to see the film showing exactly how it would look to die in an unrecoverable spin!

Please pay attention to the text and numbers in Dave’s video… That’s the time & date allright but look closer… ALTITUDE – AIRSPEED – Engine RPM and Dave’s Callsign, KI4HVT. If that isn’t enough to knock off your socks, look at his next video!

What modeler hasn’t dreamed of putting lights on his plane so he could fly at night? I must say though, it NEVER occurred to me to light up the WHOLE airplane! Very ingenious, Dave!

The cherry on top has to be the orchestrated, stereo background music to emphasize what you’re looking at. How would you like to be able to take these two films back to the ‘40s and show them to the pioneers that started all this? ULTIMATE! … Absolutely ULTIMATE! I am totally impressed and I have been around and seen a lot of stuff! Who is going to represent the next generation of modelers to top this? 2008 is going to be a good year!

Johnny
 
Fly Your Radio  
by AB0O on January 1, 2008 Mail this to a friend!
Excellent article. Brings back fond memories.
I began free-flight and CL modeling in 1964, RC flying in 1972, and Ham Radio in 1981, and my RC radios are on 50Mhz, and have been so for a long time.
Great hobbies, both are.

John
 
Fly Your Radio  
by K6LHA on January 1, 2008 Mail this to a friend!
W4XKE posted:

"Gee whiz, I didn’t know there was such a swell bunch of experienced modelers in our midst. By the way George, thanks for posting the link to Jim Walker’s page in your comment. Jim was definitely one of the ‘greats’ of the day. I wish I’d had opportunity to meet him. I’d like to encourage each one of us to look at this web site and to click on each link that is provided on the site. It is very, very interesting reading for us boys!"

"Let me also offer these additional 3 links that tell a video story of a model airplane meet of long ago. It provides some more wonderful nostalgia: Plymouth Dealer’s 1947 Model Contest:"
-------------
I sort of remember a Plymouth Dealer's 16mm version film that was presented to our Rockford, Illinois model club. It inspired me to try for the Detroit 1948 Plymouth Internationals. Made it, got 2nd in Class A Gas, free-flight, with a Comet (Carl Goldberg's) Interceptor, Junior Age Class. New AMA rules for '48: 15 second engine run, first two flights counted for 10 maximum minutes. Dethermalizer on the Interceptor failed and thermals and wind carried it faster than I could run. Free-flight in the 1948 Internationals was held at a USNR field and dress-white sailor pairs did the timing. The one stop-watching my engine run showed me exactly 15.0 seconds...just made it. The second sailor timed the whole flight while the first kept checking the 10 minute mark and keeping the model in sight. My Dad tried to get a 'radio truck' the USNR supplied but all were out following others. Two months later a kind farmer found the Interceptor after it had been diagonally chopped by a corn-picker. I got it back by mail and the engine plus spark plug ignition was still intact.

First place winner had 12 minutes plus in total time for three flights, flew early that morning. Second place at 10 minutes even wasn't bad, nice trophy and $100 (!) check. Why Plymouth was sponsoring all those contests at the time is still a mystery to me.

Simultaneously with modeling in 1947 I had wanted to learn more about radio control, having seen a Walker demo flight near Chicago. Would have been great to avoid those flyaways from thermals afflicting free-flight. The AMA forbade R/C on contest free-flights in '48 or '49.

The war surplus hoard hit the only local 'electronics' store in late '47 and I got some brand-new ARC-5 things to play with in order to learn more about this 'radio' thing. No sooner had I finished on Rx-Tx (after learning about simple power supplies) I got an offer to buy it by a returning vet from WWII. Happened twice. With the $100 from Plymouth and a modest (very) profit on the ARC-5 conversions, I bought a National NC-57 communications receiver.

So far, that should be a standard 'how I got into ham radio' story. Several things happened in 1948 to modify it: I became a professional modeler during summer vacations and some weekends, working as an assistant in Testor's model shop. The Buckbee Street plant was only five blocks from my house. My Dad had become the woodshop superintendent and responsible for all the nice sheet and block balsa wood from Testor's. SIG of Montezuma, IA, would later find out how it was done by 'visiting' the place one weekend; security was almost non-existant there. Testor's had teamed with Duro-Matic Products of Santa Monica (makers of the McCoy 'Red-Head' engines) and the new kit line was for U-Control. I drew the plans for the Fresh-Soph-Jr-Sr series kits and made prototypes, had to learn to overcome dizzyness while flying them. Testor's had made some solid scale kits, was venturing some interesting formed-wood-sheet scale kits (didn't sell).
I had no problem getting balsa or their stock-in-trade, 'dope' (the lacquer as we called it). By '49 the model shop moved to the other office in Rockford where the chemical labs were...Testor's began selling hot fuel (methanol with nitropropane additive plus castor oil) and I banged fingers starting engines in a small spray booth in the chem lab (chemists HATED that), learning to use a GR Strobotac to record engine RPMs. Didn't have the specialized instruments available now.

1949 was the start of my senior high school time and I was getting to know the nice young blonde lady who would eventually become my wife. Outside of making her an instant-on AM BC radio using battery tubes, radio consisted of trying to get Chicago TV signals from 90 miles away (no local TV stations yet). Amateur radio interest? Not strong. I helped my Dad and Testor's at the Model Hobby Shows in Chicago and did the high school activity thing. Korean War broke out in June, 1950. After a year of work after high school I volunteered for the US Army in March 1952, somehow managed to get into the Signal Corps, learning to be a microwave radio relay operator-maintainer. New stuff. Got an assignment to the Far East in January 1953, wound up at the transmitter site of the 3rd largest station in the Army worldwide net. That is described in a photo essay I put up on Hal Hallikainen's website download area: http://sujan.hallikainen.org/BroadcastHistory/uploads/My3Years.pdf

That three years was total immersion in HF communications plus state-of-the-art in microwave communications circa 1950. It changed my eventual career goals of industrial illustrator to electronics engineering and beginning a career in electronics of aerospace here in California. 26 years ago I put my hands on the combustion chamber of an SSME at Coca Site in Rocketdyne's Santa Susanna Field Test Site, wondering how in the world it could produce TONS of thrust out of a beachball-size chamber? Rocketdyne was exploring possibility of replacing the on-board engine computer with a Motorola MC68000-like processor to replace the Minneapolis-Honeywell strap-on engine controller. [throttleable liquid-fuel engines couldn't measure liquid oxygen flow so the computer did it for them by temperature and pressure calculations...LOX would eat up conventional flow meters then] So, solid-state computers on rocket engines, the integrated circuit here to stay, transistors making multiple-quantum-leaps in all of electronics. And a bunch of old-timers of amateur radio demanding all HAD to learn morse code to get a HOBBY license? I did that right after the code test was tossed. For my retirement fun and games.

By the way, Testor's changed, Nils Testor had left this world, succeeded by his partner from Duro-Matic Products, Charlie Miller Sr. Testor's stopped producing stock balsa, got into plastic scale kits, moved their plant in Rockford. Charlie Miller Jr took over from his Dad. Charlie Jr's sister is actress Susan St. James; I had seen her as a very young child long ago. Wasn't impressed by her, only meeting and talking with some Model Hobby Names, one of those being Carl Goldberg. Testor's is still in business, remarkably, but it is DIFFERENT. :-)

I never did finish my 1947 R/C project, couldn't afford the transmitter parts at the time. AMA and the Model Hobby Industry lobbied for and got 100 channels at 72 MHz and R/C was never the same as the olden days. The closest I ever got to R/C was finding a source of interference with a movie-TV special effects group (another SFX company, brokered a change in channels and everyone was satisfied). R/C and its parts are used often in the movie-TV industry here in Los Angeles, notably for puppets and anything else that will move on command. Besides the actors.

My last bottle of Testor's 'dope' was used up three years ago, as resist for a PCB one-of-a-kind. Lacquer works wonderfully well for that but the 'fuel-proof' kind sold since 1960s not so well. Acetate good, nitrate marginal. Now I use clear lacquer from a do-it-yourself chain, dye it black with a lacquer compatible dye liquid (from a local plastics company).

73, Len AF6AY
ex AMA-19700
af6ay@arrl.net
LenAnderson@ieee.org

 
Fly Your Radio  
by KC2SKG on January 1, 2008 Mail this to a friend!
Great Article!

I would love to build one, right after I finish reading, and absorbing, the 2008 handbook.

So little time, so many hobbies!!!

73's

KC2SKG
 
RE: Fly Your Radio  
by W4XKE on January 2, 2008 Mail this to a friend!
Len, AF6AY, that's a fantastic story! It's really cool to have someone that was actually THERE, being a part of it! We have obviously missed out on a lot and it's too late to go back and do it over. Thanks for sharing that with us.

Another link that should be of some interest; here’s a 3D model airplane demonstration that is quite remarkable:

http://www.youtube.com/watch?v=Gulv_bvZS94

This guy would have been able to master multi-channel, full-house reeds!

Johnny, W4XKE
 
Fly Your Radio  
by WA2JJH on January 3, 2008 Mail this to a friend!
Nice work!! I saw a demo at a hamfest many years ago.
Were you the OM that had the RC plane that had a video camera and 440mhz TX in it?

I saw this at Dayton or Timonium. The camera was in the tail. Some joked that they could see the bargains without the long walk.

Radioshack now sells a hydrogen powered rocket.
Hydrogen gas is extracted from water by a very efficient "Hoffman device". The rocket is sold as a toy. I guess it could not support the weight of a micro
sized 440 TX and camera.

Great artical. Good details. R/C is a great attraction for ham radio. Keep up the good work.
 
RE: Fly Your Radio  
by WA2JJH on January 3, 2008 Mail this to a friend!
Nice work!! I saw a demo at a hamfest many years ago.
Were you the OM that had the RC plane that had a video camera and 440mhz TX in it?

I saw this at Dayton or Timonium. The camera was in the tail. Some joked that they could see the bargains without the long walk.

Radioshack now sells a hydrogen powered rocket.
Hydrogen gas is extracted from water by a very efficient "Hoffman device". The rocket is sold as a toy. I guess it could not support the weight of a micro
sized 440 TX and camera.

Great artical. Good details. R/C is a great attraction for ham radio.
 
RE: This is SWELL ... even for a HAM!  
by KI4HVT on January 3, 2008 Mail this to a friend!
Johnny (W4XKE)- Thank you very much for the kind words. That has to be the most complimentary thing anyone has ever said/written about me! Thanks! In case you are interested, I am also working on a head tracking system where the user wears video goggles that has a gyro attached. The gyro senses the user's movements and moves the camera inside the aircraft for co-ordinated pan and tilt. This gives the illusion of actually being inside the aircraft. Another project is an autopilot system that guides the aircraft from gps waypoint to waypoint. The waypoints are created in Google Earth and sent to the autopilot as a text file. In the event of radio failure, the aircraft returns to take off gps coordinates and loiters overhead at a preselected altitude. Please note, I am not the inventor of these devices, mearily the assembler of components designed by much smarter individuals. :)
-dave
KI4HVT
 
Fly Your Radio  
by KE4GRP on January 3, 2008 Mail this to a friend!
Nice article and nice comments.

Whenever I fly out at the Columbus Areo Club, I always talk up Ham radio. What a great combination of hobbies.

I love flying helicoptors and lately, have gotten into planks.

de Ke4grp
 
RE: Fly Your Radio  
by K3UD on January 3, 2008 Mail this to a friend!
This thread is outstanding in every way!
Great Read.

BTW... it was model aviation that led me to become a licensed private pilot in 1972. I have talked with many hams who are pilots. Astronomy also seems to be another hobby that hams also enjoy.

73
George
K3UD
 
RE: Fly Your Radio  
by N7YA on January 3, 2008 Mail this to a friend!
Whats outstanding about this thread is the fact that it provides very little for that online ham subculture to throw negativity into...i agree, outstanding article!
Weve come this far and everyone is still being really cool and into it, every so often an article comes along like this, we need MANY more.

Just goes to show, some folks thrive in negativity, and the rest of us are here to work hard so we can enjoy our lives, family and hobbies. Keep up the good work. :-)

73...Adam, N7YA
 
RE: Fly Your Radio  
by KF3CW on January 4, 2008 Mail this to a friend!
Very nice article. I actually attended my first Radio Control Meeting at Walt Good's house as a member of DCRC in 1976. Walt was a Scholar and a real gentleman and his wife made "real good" cookies. This was a start to a great hobby for me and I use the 50mhz portion of the amateur radio band to fly my many model airplanes and helicopters on today. I didn't get involved in amateur radio until 1997 - but enjoy the DX and rag chewing portion of the hobby when I'm not flying my models.
 
Fly Your Radio  
by N2BLZ on January 5, 2008 Mail this to a friend!
Hi All,

I sent this email to Johnny and he ask me to put it on the forum:

Hi Johnny,

A friend sent me your article. I enjoyed it very much. I thought you'd like to know a couple of things.

In the film there is a shot of (L to R) Walt, Lester and Bill. Lester was their father and Bill is my Dad.

To the best of my memory, that part of the film was taken at the 1940 Nats.

Also, my Dad's call sign back then was W8IFD. When he moved to the District 2 it was changed to W2CVI,

and remained that until his death in 2001.

Thanks again for a very nice article.

Gary Good, N2BLZ

 
Fly Your Radio  
by K6LHA on January 5, 2008 Mail this to a friend!
Can anyone suggest some source for the technology of present-day R/C electronics? Something more than the "R/C for Dummies" simplified sort.

I'm somewhat familiar with the 'reed' type that got started with the initial 'Bell Boy' pager from AT&T and wasn't too happy with that. In the mid-60s I did some experimentation with a digital system, intending to use it on the 23 cm band...ran into some bad spark transmission from early DC motors of the brush kind and that proved unsolvable back then. Intended to do full R/C over a 30 mile distance and back...something which has since been far ecipsed by others. Crossing the Atlantic was so much greater and such an accomplishment that it isn't worth trying to surpass now. :-)

Still, I think it is an area worth looking into now with the present systems. But, to do that requires some knowledge (up close and personal) without having to buy a system just to 'reverse engineer' it to find out how it works in intimate detail.

Suggestions are welcome.

73, Len AF6AY
ex AMA-19700
 
RE: Fly Your Radio  
by W4XKE on January 5, 2008 Mail this to a friend!
Len, AF6AY asked, “Can anyone suggest some source for the technology of present-day R/C electronics?”

A Google search for digital radio control theory will result in many sources of information on modern electronic design and practice. I have selected a few to present here as an example that should get you started in the right direction.

I included the link to an electronics design lab to illustrate modern methods of circuit development. While this particular lab is rather limited in scope, you can get the general idea of using these tools. You can select an electronic component from the toolbar and drag it into your circuit. Usually a right click will open a box where you can assign a value to your new component. Drag the mouse from node to node to connect the components.

Once the circuit is built, you can ‘turn on the power’ to see it operate with actual voltages, currents, waveforms, etc. More powerful labs are available for modest money but this freebie is a good introduction.

The more elaborate ones have test instruments such as oscilloscopes, frequency counters, signal generators, digital multimeters, etc. that you can use to check your circuit. Just drag the probes of the selected instrument to the nodes to be analyzed. You can evaluate your circuit without blowing diodes or burning off your fingerprints. Ain’t technology incredible? I love it. Johnny, W4XKE

Theory of Operation for Radio Control Systems
http://webpages.charter.net/rcfu/HelpsHints/RadioOps.html

Digital Receiver Project
http://www.tcrobots.org/articles/microrx.doc

Electronics Design Lab
http://www.cs.technion.ac.il/~wagner/index_files/ckt_anim/

Library of Electronic Circuits
http://www.educypedia.be/electronics/circuits.htm
 
RE: Fly Your Radio  
by K6LHA on January 6, 2008 Mail this to a friend!
W4XKE posted on 5 Jan 08:

Len, AF6AY asked, “Can anyone suggest some source for the technology of present-day R/C electronics?”

"A Google search for digital radio control theory will result in many sources of information on modern electronic design and practice. I have selected a few to present here as an example that should get you started in the right direction."

Thanks, Johnny, the first link was a help in getting me up to speed on present-day systems.
..........
W4XKE: "I included the link to an electronics design lab to illustrate modern methods of circuit development. While this particular lab is rather limited in scope, you can get the general idea of using these tools. You can select an electronic component from the toolbar and drag it into your circuit. Usually a right click will open a box where you can assign a value to your new component. Drag the mouse from node to node to connect the components.
Once the circuit is built, you can ‘turn on the power’ to see it operate with actual voltages, currents, waveforms, etc. More powerful labs are available for modest money but this freebie is a good introduction."

Good on that. But, as an old hand with CAD and CAE, I would suggest another freebie which turns out to be a full-featured SPICE program from Linear Technology (the IC folks). It originally came out as a booster for their switchmode power supply ICs but Linear expanded it to include ALL devices. The installable program is available from:

http://www.linear.com/DESIGNtools/software/switchercad.jsp

The name was originally SwitcherCad but it also known there as LTspice. I've used it for a couple of years and it compares very favorably with other expensive SPICE packages. The schematic drawing program is simplistic but it works fine for making a netlist automatically, will let you know if a connection was missed on the drawing.

Note: LTspice has been upgraded over the last 3 years and it is easier on download time to get the full .EXE package and unpack it, install it, off-line. I found that out when informed I hadn't upgraded it for a year and a half. :-)
..........
W4XKE: "The more elaborate ones have test instruments such as oscilloscopes, frequency counters, signal generators, digital multimeters, etc. that you can use to check your circuit. Just drag the probes of the selected instrument to the nodes to be analyzed. You can evaluate your circuit without blowing diodes or burning off your fingerprints. Ain’t technology incredible? I love it."

Computer simulation technology is great, I agree! I was a latecomer to it in 1972 (variation of the old IBM ECAP used by RCA Corporation) and that got me started full-bore in programming computers. :-)
...............
W4XKE:

Theory of Operation for Radio Control Systems
http://webpages.charter.net/rcfu/HelpsHints/RadioOps.html

Nice set of pages. I was hoping for a bit more on timing windows, allowances for same, and whether or not the channel signals were pulse-position-modulation or pulse-width-modulation? And the time range of those?

It's been a very long time since the Raytheon RK-61 regenerative thyratron single-tube rudder-only R/C and 'plate relay' to sense a signal...not to mention the rubber-band-powered escapement as the precursor to the modern servo. As to modeling, my fingers were long ago healed from all the hand-starting prop kickbacks of the little gas engines. I still like the sweet smell of acetone in the 'dope' and glues. Oddly, the old X-Acto knives have continued to be produced since the end of WWII! :-)

73 and TNX, Len AF6AY
 
Fly Your Radio  
by G0WSP on January 7, 2008 Mail this to a friend!
Loved the you tube clip Johnny.
I recently got back into R/C after a 20 year break, was a glider and yacht fan but always wanted to fly a Heli - with the battery and micro revolution , WOW !how the technology has changed.
We now have a number of R/C fans in our radio club !!
73 de Phil
Hope you like our link
http://www.youtube.com/watch?v=O7fG-G0ndkI
 
RE: Fly Your Radio  
by W4XKE on January 9, 2008 Mail this to a friend!
We can see by this last video clip that radio control has improved remarkably since those early days when simple turns were a major accomplishment. Phil, G0WSP certainly demonstrates his dexterity and his confidence, flying a helicopter indoors with a room full of people! Thanks, Phil.

Several hams and modelers have emailed me to express their appreciation for the detailed radio history piece that I posted in the comments of this article. Having today made contact with the author of that information, I’d like to give credit to him for his fascinating material. Known by the username, “jaymen” you can find many more interesting facts that he has posted in the forums at

http://www.rcuniverse.com/index.cfm

Jay is undoubtedly a very unique, knowledgeable and friendly individual. Here is an excerpt of his email to me:

“ My name is Jay Mendoza. I worked for Cox, Airtronics, Tekin, and Futaba over a 15-year period. I met and married my wife at Futaba. She stayed on there until they moved to Illinois, when I left for a great job in aerospace/telecom. From time to time I post-technical discourses on RC Universe about how each type of radio works. If you do a search on "jaymen" as the author on RC Universe, you can find pictures and other tech articles I have done. There are some nice pictures of several Galloping Ghost systems and a plane I'm building with one installed on that site, take a look.
Zel Ritchie and I have struck up a good friendship, I see him all the time. We work on old radio together; it's fun. Regards, Jay, (ex) K6KVK ”

I’d like to offer a very special thanks to Jay for sharing his wealth of knowledge. I fear that much of this early history might well have been lost without his firsthand experience and recollection of the events as they occurred. Thanks Jay!

Until recently, I didn’t know much about the people and the circumstances that brought about those first digital proportional control systems; only the product names and the features they provided. Now it all has taken on a lot more meaning and I have a greater appreciation.

Whether we spend our Saturdays chasing DX, gluing balsa, machining tiny engine cylinders or applying solder to our latest circuit, there is a tremendous opportunity for us to learn, share, experiment and enjoy the many aspects of our hobbies. It is these people who passionately pursue their ambitions that continue to make our leisure hours so richly rewarding.

In behalf of all hams and modelers everywhere, I’d like to say thanks for the contributions of so many people who have helped to make it all possible.

Johnny, W4XKE
 
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