Strange UHF Behavior

[Jim Frame]

I had a site today that was giving me a lot of grief with regard to UHF communications. The LS would get a few clicks, then the UHF signal would drop for anywhere from a few seconds to 30 seconds or more. After 5 minutes or so I accidentally discovered that if I lay my finger lightly against the LS case the UHF would come back. I was about 3.5 miles from my base. I had tied this point last week from the same base with no trouble. I was getting ready to fetch the external antenna when I found the finger trick.

Any of you ever seen this kind of behavior?

 

[Vladimir Zhukov]

Hello Jim,
did you attach the external UHF antenna to the TRIUMPH-LS?
what is your base station and its programmed output power?

Regards,
Vladimir

 

[Duane Frymire]

I had a site today that was giving me a lot of grief with regard to UHF communications. The LS would get a few clicks, then the UHF signal would drop for anywhere from a few seconds to 30 seconds or more. After 5 minutes or so I accidentally discovered that if I lay my finger lightly against the LS case the UHF would come back. I was about 3.5 miles from my base. I had tied this point last week from the same base with no trouble. I was getting ready to fetch the external antenna when I found the finger trick.

Any of you ever seen this kind of behavior?

Did you have your tin foil hat on?

 

[Nate The Surveyor]

All kidding aside, at the marginal edge of range, radio signals are funny things. It is possible that your body/finger is acting like an antenna, and when you put your hand there, it simple boosts the faint signal enough, to get it going.
When we were kids, we learned that sometimes standing in one place made the radio play better. Or, standing in another blocked signal, or added static.
It's easy to delve into UFO theories, discuss esp, or to think you have found a portal into the bermuda triangle, (were you wearing bermuda shorts?)
But, I think it's pure science, due to marginal signals, and the effects of the iron content in your blood, and it's blocking/collecting/or damming up effect, concentrating the rf just right.
We can speculate endlessly, but it's the interaction of the human body, with faint R/F.
Nate
PS, is your mother in law evil?

 

[John Thompson]

Any of you ever seen this kind of behavior?

I observed this same thing twice today. I have a 4W transmitter with the antenna about 12' off the ground and was less than a mile away, but down in a valley that blocked the signal. I tried the finger trick and it did just like you showed, but not as consistent. I tried to get some video, but it didn't work when I got my camera out. I also tried rotating the LS in azimuth, which proved much more repeatable. With the internal UHF antenna on the back of the LS pointed toward the base it worked, but pointed away from the base did not. I think Nate is right. Probably focusing or reflecting the signal just right somehow. Sometimes I think it would be useful to be able to see more of the electromagnetic spectrum than the tiny range of wavelengths that we can see. I'm sure the world would look very different.

 

[Jim White]

The orientation of the internal UHF antenna really does make a difference. Touching the unit makes you part of the antenna and grounding. Try holding your car key to your head when you unlock it... it probably doubles the range.

 

[Nate The Surveyor]

Jim,

Try holding your car key to your head when you unlock it... it probably doubles the range.

Jim, it made no difference. On my 1998 dodge! I think I'm a carmudgeeon. Now, I gotta go saddle up the horse.....
Seriously, I think about stuff like a large folding rf collector. In fact, I went to my local radio shop, bought a Yagi, and some wire, and connectors. I use backwards. I plug it into the LS, and use the yagi as an rf collector. It works. Total cost was maybe 100$.

N