Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
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
About eHam.net

donate to eham
   Home   Help Search  
Pages: [1] 2 Next   Go Down
  Print  
Author Topic: Given enough wire, could a person use a standard antenna tuner...  (Read 4064 times)
N0PQK
Member

Posts: 109


WWW

Ignore
« on: October 09, 2017, 02:28:20 PM »

Given enough wire, could a person use a standard antenna tuner that currently tunes the 160 meter band for the 600 meter band.

A quarter wave on 600 meters is 495 feet

Has any one in Europe or Canada tried this? If so how about something like a Palstar HF-AUTO or an Icom AH4.

No smart a$$ comments please, I know others are wondering the same thing. This is all new territory for many US hams.
Logged
VA3VF
Member

Posts: 940




Ignore
« Reply #1 on: October 09, 2017, 04:50:09 PM »

Given enough wire, could a person use a standard antenna tuner that currently tunes the 160 meter band for the 600 meter band.

It may be possible, but tuning is the 'easy' part. Efficiency is the more important issue. Have a look at the LWCA (Longwave Club of America) website for lots of info. I don't remember seeing anybody try that before, and report good results on TX.
« Last Edit: October 09, 2017, 04:55:28 PM by VA3VF » Logged
KC4ZGP
Member

Posts: 1637




Ignore
« Reply #2 on: October 10, 2017, 07:41:41 AM »


Sure.

A larger inductor and larger capacitors. Tune it down man.

A guy mentioned the Long Wave club of America. Was a member and had a beacon at 184.5KHz.

A friend of mine and I made a beacon. A ten inch diameter PVC for the coil form. The antenna
was a giant hammock of wire thirty feet high, ten feet wide by thirty feet long.

We grounded the beacon to my copper water pipes. Holy cow did it draw the RF amps. We had
that baby working so well, we could hold a florescent tube like Luke Skywalker and every time
the beacon keyed, the tube lit up like no body's business.

Oh man.

Kraus
Logged
KB4QAA
Member

Posts: 3258




Ignore
« Reply #3 on: October 10, 2017, 08:27:00 AM »

Quote
Has any one in Europe or Canada tried this? If so how about something like a Palstar HF-AUTO or an Icom AH4

As Kraus has pointed out, low frequency antennas can develop big voltages.   Using some off the shelf small tuner is going to get zapped.  I think auto tuners with small matching coils and relays will likely fry themselves as well through shorts.  

You need to be thinking MANUAL tuners with big coils, and capacitors with widely spaced plates rated for high voltages/power.  Think ATR-30 class.  

Even small changes in frequency are going to require re-tuning as may precipitation or soil conditions.  Auto tuners are for kids at high power/voltage.
« Last Edit: October 10, 2017, 08:35:22 AM by KB4QAA » Logged
VA3VF
Member

Posts: 940




Ignore
« Reply #4 on: October 10, 2017, 08:36:24 AM »

Quote
Has any one in Europe or Canada tried this? If so how about something like a Palstar HF-AUTO or an Icom AH4

Using some off the shelf small tuner is going to get zapped.  I think auto tuners with small matching coils and relays while fry themselves as well.  

You need to be thinking MANUAL tuners with big coils, and capacitors with widely spaced plates rated for high voltages/power.

I was thinking manual tuners as standard tuners. The auto tuners will likely fry themselves. Some popular auto tuners cannot handle more than 30W on digital modes, although rated to 100W.

There are some nice installations using vacuum capacitors, and inductors remotely adjusted.
Logged
KC4ZGP
Member

Posts: 1637




Ignore
« Reply #5 on: October 10, 2017, 10:03:50 AM »


Yup.

My 949D Versa Tuner was OK at 100 watts, 160 meters. But when I upped the power to just 200 watts,
the dielectric tucked around the capacitor's shaft and the steel chassis arced and made like
Cheech and Chong...up in smoke.

I ended up building a giant manual matcher for just 160 meters. A 35 micro henry roller inductor and two
4,500 volt, 200 pF air variable capacitors from RF Parts.

I'm having tons of 160 meters Morse fun.

And by the way, I found an Ameritron AL-811H on eBay. It says for parts or not working. I don't think the
individual knows what he is selling; a non-ham. He said, "I couldn't get any thing out when the exciter was
connected." I ain't never called the transceiver an 'exciter'. Hmm....

Current bid at $271.00. We'll see.

Kraus


Logged
N0PQK
Member

Posts: 109


WWW

Ignore
« Reply #6 on: October 10, 2017, 11:53:45 AM »

Kraus, I presume these inductors will be up to the task for a 10 watt transmitter on the 600 meter band.

http://www.kintronic.com/product-category/am-medium-wave-and-shortwave-products/rf-inductors-capacitors-and-contactors/inductors-and-accessories/fixed-inductors/
Logged
KC4ZGP
Member

Posts: 1637




Ignore
« Reply #7 on: October 10, 2017, 03:56:28 PM »

Holy cow. Now there's some coils. The 200 amp job looks like a shower stall.

I saw a picture of a room with coils on the walls and floor. Looked like a tuning
room for one of them international broadcasters. The old man had the white
hair the German worker hat and holding a wrench. He had a big smile on his face.

It's near 2300UTC and 1.815MHz is coming alive. Quite noisless compared to Sunday.

Kraus
Logged
N7ZDR
Member

Posts: 110




Ignore
« Reply #8 on: October 10, 2017, 08:23:05 PM »

I have said this before but will say it again--- If you like to home brew things don't buy a antenna tuner as your just wasting your hard earned money. A trip to you local hardware store will get you everything but the caps. Wind your own inductors, E bay has tons on old used caps (just be patient- the right one will come along for less then 30 bucks).
A chunk of plywood and mount the thing to you shack wall. Folks coming in to the shack will be shocked to see all the 6 inch diameter coils on the wall (look at the wall in my shack -qrz)

Kraus--- I heard you tonight on 160,you had just singed off with someone. By time I got fired up I didn't hear you any longer.
The station down on 1.802 was loud here and sounded like a ARRL bulletin??
Maybe another night.
Cheers
Larry
Logged
KC4ZGP
Member

Posts: 1637




Ignore
« Reply #9 on: October 11, 2017, 05:31:00 AM »


Larry,

Alrighty! The KC4ZGP loop works. I had slow fading. A character then a long space then
another character. A struggle to copy.

Was my fist OK? Shall we have a go at it say 8:00p.m. your time?

Yes, 1.8025MHz is ARRL's code practice and bulletin frequency. When I hear it here in Georgia, I know
I have a good chance to be heard. They boom in at S-9 +10dB.

Coils on the wall? Alrighty a tasteful shack. All I have on the wall is pictures of the Trinity, Moe Larry and Curly.

Oh and a Stooges clock.

Kraus





Logged
KC4ZGP
Member

Posts: 1637




Ignore
« Reply #10 on: October 11, 2017, 05:36:57 AM »


Larry,

Yow. Look at those coils. Those are two L-network matchers?

I use a trombone capacitor for my magnetic loop. Two sizes of copper tubing and yo-ho-ho!

"Get rid of those plated caps and go trombone." I always say.

160 is the fun band.

Kraus

Logged
KC4ZGP
Member

Posts: 1637




Ignore
« Reply #11 on: October 11, 2017, 05:38:43 AM »


N0PQK,

How goes the 630 meters coils project. Look at Larry's picture of his 'coils in the shack'.

Scooby-doobie-doo.

Kraus



Logged
AA2UK
Member

Posts: 379




Ignore
« Reply #12 on: October 11, 2017, 08:39:06 AM »

You really want the 630 meter tuner at the base of the antenna. That's lots of amps and high voltage to have mounted on the shack wall. It should be installed near the antennas ground system at the feed point.
Bill AA2UK
Logged
VA3VF
Member

Posts: 940




Ignore
« Reply #13 on: October 11, 2017, 09:06:09 AM »

You really want the 630 meter tuner at the base of the antenna. That's lots of amps and high voltage to have mounted on the shack wall. It should be installed near the antennas ground system at the feed point.
Bill AA2UK

Yes... the insurance company would not look very favorably to a fire claim of this sort.  Grin
Logged
AA2UK
Member

Posts: 379




Ignore
« Reply #14 on: October 31, 2017, 08:42:11 AM »

I think the title of the thread should be given enough wire and antenna height could one use a conventional ATU or no ATU at all.
Bill, AA2UK
Logged
Pages: [1] 2 Next   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!