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Random Wire and no tuner.

Dan Baker
 

 So what I’m considering doing is letting the ultimate 3S band hop into say a 60 foot random wire antenna. I guess the worst that can happen is I have to replace the BS170. Has anyone tried this?

Thanks,  Dan KM6CQ 

 

After 45+ years of doing beams, resonant antenna, and careful attention to detail, I simply stopped worry.

I have spent many afternoons in the local woods/ gravel pit clearing, taking a random length from the corner pile of my garage, another random length for a ground wire, and that's it. I have yet to have an afternoon without sunshine, conversation and many happy CW contacts.  I do the same with my WSPR and QCX contacts on 40M.

I generally run 3 watts or less and have never had to replace a BS170 yet. But I seem to enjoy the afternoon ham time more than ever !  This is about having enjoyable fun, isn't it !

Frank  W1FRA

James Anderson
 

Hi Dan. 

I used to use a short approximately 5 metre piece of wire with no ground other than the PSU ground, if that made any difference. 

Literally hanging out of the bedroom window on 40m. 

Only TX with very low power, single transistor with no detrimental effect on the poor U3S. 

This is my spare U3S out of three so if the final went pop, it wasn’t the end of the world. 

I’ve plenty spare HiHi. 

I did get spots. Nothing earth shattering but it was still very surprising what can be achieved. 
Just do it and see where you can get too. 

Kindest, James. 



On 9 Jun 2019, at 17:49, Dan Baker <km6cq@...> wrote:

 So what I’m considering doing is letting the ultimate 3S band hop into say a 60 foot random wire antenna. I guess the worst that can happen is I have to replace the BS170. Has anyone tried this?

Thanks,  Dan KM6CQ 

SkipF, NT1G
 

The 'army' had a long wire fed by a 50 ohm resistor, mainly to protect
the final tube.

On Sun, Jun 9, 2019, 12:49 PM Dan Baker <km6cq@...> wrote:
 So what I’m considering doing is letting the ultimate 3S band hop into say a 60 foot random wire antenna. I guess the worst that can happen is I have to replace the BS170. Has anyone tried this?

Thanks,  Dan KM6CQ 

Alan de G1FXB
 

Not 60ft, I run mine into a random length around 15ft at 9Ft AGL

Have to admit, I run it through a 3dB attenuator to mitigate the unknown mismatch, the downside I loose half my RF.
Has run that way since 2013, single BS170 at 5V and works fine, don't sweat it.


Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az
??2019-06-08 09:06?? ??G1FXB?? ??7.040103?? ??-8?? ??0?? ??IO91?? ??0.1?? ??VK4ICE?? ??QG62nr?? ??16563?? ??49??
??2019-06-04 12:10?? ??G1FXB?? ??14.097106?? ??-11?? ??0?? ??IO91?? ??0.1?? ??FY5KE?? ??GJ35?? ??6988?? ??242??
??2019-06-09 13:48?? ??G1FXB?? ??28.126094?? ??-23?? ???????? 0?? ??IO91?? ??0.1?? ??SQ5ALQ?? ??KO02hi?? ??1484?? ?????????? 78??
??2019-06-08 22:48?? ??G1FXB?? ??28.126159?? ??-23?? ??0?? ??IO91?? ??0.1?? ??IZ0FKE?? ??JN61fw?? ??1474?? ??131??
??2019-06-06 09:18?? ??G1FXB?? ??28.126106?? ??-17?? ???????? 0?? ??IO91?? ??0.1?? ??EA1GAR?? ??IN52pb?? ??1197?? ?????? 212??
??2019-06-09 09:18?? ??G1FXB?? ??28.126112?? ??-10?? ???? ?? 0?? ??IO91?? ??0.1?? ??LA3FY/2?? ?????? JP40fj?? ??1152?? ?? ?? ?? 27??

On 09/06/2019 17:49, Dan Baker wrote:
??So what I???m considering doing is letting the ultimate 3S band hop into say a 60 foot random wire antenna. I guess the worst that can happen is I have to replace the BS170. Has anyone tried this?

Thanks, ??Dan KM6CQ??

Dan Baker
 

Thank guys. Those are my thoughts as well. I have plenty of wire and room so I thought why not?  I can let it band hop this way and forget about resonance since 200 mW seems to cover a multitude of sin.  

Dan 

John Kirby
 


98% end fed wire antenna since 1957

They work
Easy to hang
Easy to feed
Portable
Height not critical and slopers more directional than horizontal
Add a tuner (for 1:1 SWR) (if that's you thing)(most bands) 

Wire lengths to avoid
https://udel.edu/~mm/ham/randomWire/

72 73
John
N3AAZ

Bill Cromwell
 

Hi,

I have been a fan of end fed wires and other antennas used in a multi-band role. That SWR of 1:1 for a 50 ohm load is not just to keep finals happy. I have also noticed that most of the radios don't care about that. What does care about that 50 ohm load is the output filters that are designed for a 50 ohm load. We are depending on those filters to keep our harmonics off the air. You do care about that don't you?

I have a lot of on-air hours with tube finals and pi output networks. My procedure was to tune up the pi-network into a 50 ohm dummy load, Then switch to the matcher (aka tuner) and show the (now) 50 ohm pi network the 50 ohm load it is set to. Whatever happens to the clean signal at the antenna end of the feedline enough of it escapes into the ether to be heard. So don't be too cavalier in dismissing the match between transmitter and feedline.

73,

Bill KU8H

On 6/9/19 5:45 PM, John Kirby wrote:
98% end fed wire antenna since 1957
They work
Easy to hang
Easy to feed
Portable
Height not critical and slopers more directional than horizontal
Add a tuner (for 1:1 SWR) (if that's you thing)(most bands)
Wire lengths to avoid
https://udel.edu/~mm/ham/randomWire/ <https://udel.edu/~mm/ham/randomWire/>
72 73
John
N3AAZ
--
bark less - wag more

Braden Glett
 

Why do you operate in a gravel pit? Doesn't that block all the signals except for NVIS? Just curious about your experience with that. Thanks.
Braden

 

It is a big wide open gravel pit area. Probably half mile across.  80% is woods on the sides. The owner lets me have free run of the place . 40M during the day I usually work into Europe , the Southern States, lots of East Coast. lots of South America during sunrise and sunset.

On Mon, Jun 10, 2019 at 10:11 AM Braden Glett <bradenglett@...> wrote:
Why do you operate in a gravel pit? Doesn't that block all the signals except for NVIS? Just curious about your experience with that. Thanks.
Braden

Bill Cromwell
 

Hi,

Not all parts of all gravel pits is below grade.

73,

Bill KU8H

On 6/10/19 10:52 AM, Frank W1FRA wrote:
It is a big wide open gravel pit area. Probably half mile across.  80% is woods on the sides. The owner lets me have free run of the place . 40M during the day I usually work into Europe , the Southern States, lots of East Coast. lots of South America during sunrise and sunset.
On Mon, Jun 10, 2019 at 10:11 AM Braden Glett <@kd8zm <mailto:@kd8zm>> wrote:
Why do you operate in a gravel pit? Doesn't that block all the
signals except for NVIS? Just curious about your experience with
that. Thanks.
Braden
--
bark less - wag more

ajparent1/KB1GMX
 

Dan Baker,

Two things to get best results...

Use a 1:9 transformer (unun) to match the antenna better.
Add a counterpoise  wire of any convenient length, though
around 10M should be enough.

Allison

Dan Baker
 

Hi Allison. 
Thats exactly what I was thinking. I would wind a 9:1 transformer. Then I could mount the radio on the other side of the wall and run a 1ft just jumper from the radio to it. That should help to minimize loss

Thank you, Dan  

Dan Baker
 

Thank you for your comments Bill. 
I am not too concerned about stressing the components since I’m only running 200 mW however, I did not consider spectral purity.  I will use my SDR receiver to look at the IMD on each band it transmits on and determine whether or not it is in compliance.

73, Dan

Stephen Farthing G0XAR JO92ON97
 

Hi Dan, 

There is a fairly active end fed antenna group on Facebook plus some videos on YouTube on how to make the transformer plus the choke balun by Steve Ellington W8JI.

If you are at all interested in what’s going on with your aerial you could do worse than invest in one of the SARK analysers which are available on eBay or from one on the Chinese auction sites for little money. With one of these it’s possible to tune your end fed and do away with the need for any tuner at all. 

Regards 

Steve G0XAR