Call Search

New to Ham Radio?
My Profile

Friends Remembered
Survey Question

DX Cluster Spots

Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement

donate to eham
   Home   Help Search  
Pages: Prev 1 2 [3] 4 5 6 7 8 ... 10 Next
 on: Yesterday at 07:34:40 PM 
Started by KI7LFD - Last post by K4RVN
I ran my 5 band hex beam for some time without a thrust bearing. The mast was 12 ft. I did install a very inexpensive Yaesu thrust bearing when I replaced my 20 plus year old rotator. I have 10 ft. sticking up beyond the thrust bearing now on my K4KIO 5  band hex beam and HD73 rotator. It has been up several years with no problem. The wind load and weight is easily handled by the HD 73. The hex beam does not tend to coast when the rotate lever is released due to its' profile.
I have had the hex beam up for about 8 years now without antenna problems. Mine is on a Hazer I modified.


 on: Yesterday at 07:05:07 PM 
Started by NW7US - Last post by HFCRUSR
NW7US good to catch ya here. How's the pipes?? I'm not a ham but have a pretty decent listening shack here, replete with 3 antennas, 4 comms receivers, one being a boatanchor...and a couple antiques. When I was little my 1st SWL radio is (still have it) a little blonde AIWA AM/FM/SW model AR-123. Most I ever got on that one with that little whip was R. Moscow, WWV, CHU, and the Woodpecker from my little desk in my room in Itasca, Ill. But what "hooked" me was my grandma's Grundig Majestic console with the German and right-to-left tuning. It was running on a TV aereal on her roof and got tons on SW. I was the only one using that thing if it got any use at all. Then when I was about 10 my uncle gave me a '64 Zenith TO 3000-1 (still have that one too) and from that beauty on I've remained addicted as hell, almost inexplicably, to this SWL mystery.

 on: Yesterday at 07:04:07 PM 
Started by KI7LFD - Last post by KI7LFD
This spring I'll be installing a 40' tower out behind my barn. I intend to place a hex beam antenna on top of the tower with a small rotator to spin it. ( Considering a  Yaesu G-450A. The G-450A handles a wind load of 10 Sq. Ft. and a vertical load of 242 lbs.) So, I'm proposing 10' of mast from the antenna to the top plate, with the remaining 10' under the top plate connecting to the rotator. The top plate would of course have a thrust bearing. (So, hex beam to 10' of mast to a thrust bearing, then thrust bearing.....followed by another 10' of mast to the rotator.) The 20' mast itself would be made of cold drawn steel with 2" OD, with a yield strength of ~ 50,000 lb/in squared.

Several of the rotator manufacturers indicate that the max. distance from the antenna to the thrust bearing should be limited to a meter (~ 3 1/4 feet). Whereas, I'm proposing 10 feet between the antenna and the thrust bearing. The hex beam weight is ~ 25 lbs and the wind loading area is 5.1 sq. feet.

This seems like a sensible design and I believe I'm being reasonable in my approach.

Any comments and feedback would be appreciated.

Rich  (KI7LFD)

 on: Yesterday at 06:59:12 PM 
Started by KJ6DRG - Last post by W6EM
Any relays, of course.  And, the solenoid operated water valve(s).  Might be useful to control a garden hose operated sprinkler with....

 on: Yesterday at 06:57:20 PM 
Started by KB8CSL - Last post by N3DT
Boy, this goes back to 2009. But yes the ALC is not really necessary, but if there's a lot of overshoot on the driving rig, it may be somewhat problematical, but most of the time not. I don't even run up the ALC on my TS2000 and AL80B combo. I keep the 2000 at about 70W out which usually gives me 7-800W out registering on my LP100A, which I trust.

 on: Yesterday at 06:52:47 PM 
Started by N5PG - Last post by K6UJ
Anyone who has concerns or questions the ability, knowledge, skill, and experience of this DXpedition team should see this lineup, which says it all. This is not just a bunch of guys who got together one day and decided to get on a ship and go to Bouvet.

As for $$$NA or $$$USA spots, I've seen that coming out of Europe when they had 70% of the QSOs.

I agree 100% Hal.   It is evident Zenki is naive about DXpeditions and the Bouvet team.  Perhaps he is trying to prove he is a ham with his rambling.   Cheesy


 on: Yesterday at 06:50:46 PM 
Started by AA4PB - Last post by N3DT
Don't know about youse guys transceivers, but my TS2000 has an adjustable transmit bandwidth. When I use FT8 I kind of max it out. It does make a difference how much power you put out at the extreme ends of the spectrum. I can see it on my LP100A. YMMV. Now why these guys stick to the bottom, anyone's guess.

 on: Yesterday at 06:45:48 PM 
Started by N5PG - Last post by KB8GAE
Is 3y0Z going to be a "verticals on the beach" operation or will they be using decent antennas. Theres no information on their web page on the planned antennas   that will be used.

Here is a link to the proposed camp and antenna layout.

This is a first-class, top-notch team and they will do their very best to work every station, regardless of location, that they possibly can.


Rich  KB8GAE

 on: Yesterday at 06:30:03 PM 
Started by K1VCT - Last post by HAMHOCK75
I restored an old 5BTV with two bad traps. In the process, I asked Newtronics about how to set the traps up after I worked on them. They sent instructions for a physical alignment but no information about what the resonant frequency is supposed to be. I measured the resonant frequencies and all the traps are resonant below the band for which they are labeled.

The tube below the 10M trap is too short to resonate on 10M but adding the tube above the 10M trap makes it too long. So the 10M "trap" is a capacitor on 10M raising the resonance of the two sections to 10M. It is actually even more complex because of the interaction of the higher sections.  

Also, the antenna is closer to 1/8 wavelengh long on 40M so the radiation resistance at resonance is much lower than on 10,15,20M but a poor ground which adds series R can make it look good. I added radials two at a time and noticed every time I added a pair of radials, the 40M swr got worse but it was still resonant on 40M.

No one asked but I was curious if the radiation pattern was changed by having an arrangement where radiation occurs above above the trap. I did an EZNEC analysis which showed virtually no difference.

 on: Yesterday at 06:27:43 PM 
Started by NW7US - Last post by WA2ISE
Listening to rock and roll on the AM radio, wanted to know the technology behind it.  Later I dabbled with (gasp!) CB.  Then wanted to do "real" radio, and got my tech plus in 1976.  Got my extra in 2000.  Also majored in electrical engineering and got my BSEE in 1978 Syracuse U.  Cheesy

Pages: Prev 1 2 [3] 4 5 6 7 8 ... 10 Next
Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!