Hi Lee,
The only thing I've noticed are some pops going on some of the receive antennas
that I think may be an electric fence or some power line arcing. They are about
1-2 seconds apart. I see them sometimes and I can see it causing the AGC on
fast to cut back the gain on the receiver. But that does not sound like the
constant static I hear.
Just bought some new RG-6 coax from Norvac to replace this old stuff and make
sure it's not that. Also got some resistors and 'gators' for checking my 4:1
and 9:1 XFMR's like Tree was telling me. Also got some fence post and 1 1/2"
PVC to put up a NE beverage that I hope will reach at least 400 feet or better.
Terry
KI7M
> On January 13, 2018 at 11:50 AM Lee STRAHAN wrote:
>
>
> Hello All,
> I may not have seen all of the posts on this topic but will comment
> anyway.
> Two things come to mind about this noise. Number one is you do not want
> to connect the shield of the coax going to the receiver to the ground stake
> for the antenna. It's important that the transformer you use has an isolated
> winding for the output to the cable leading to the shack. The other comment
> is you may have some local arcing or digital noise that the Tx antenna does
> not hear. The best clue to checking for this is to use the AM mode on your
> receiver and listen for the characteristic hum from a power line or switching
> supply.
> Good Luck
> Lee K7TJR OR
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces@contesting.com
> mailto:topband-bounces@contesting.com ] On Behalf Of terry burge
> Sent: Saturday, January 13, 2018 11:09 AM
> To: David Olean ; topband@contesting.com mailto:topband@contesting.com
> Subject: Re: Topband: Topband Digest, Vol 181, Issue 16
>
> Hello Dave and Group,
>
>
> I had responded directly to Martin and will include my comments to him.
> Right now I hesitate to pull the tape off the coax at the XFRM but will do
> that ASAP to check it out. When I took it off the old spool it had not been
> used but it is donated to me from a junk yard lot. I also got a 4 foot spool
> nearly full of 1/2" hardline I'm planning on replacing my ground run of
> LMR-400 with. 75 ohm but it should work if I can build the connections to the
> LMR-400 PL-259's, etc.
>
>
> Disconnecting the ground as well as the BOG (in this case) from the XFRM
> causes the noise to drop down to about S-1 to S-2.
>
> With ground connected to the XFRM I get about S-5 noise level without any
> antenna.
>
> Per my note to Martin you can read my other test. Right now with the
> 550-600 ft. beverage hooked up along with ground of course, I get S-5 noise
> level and can't hear an S-9+10 over signal on 7.235 Mhz.
>
>
> Terry
>
> KI7M
>
> ---------------------------------------------
>
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