[amsat-bb] Re: Frustration

Bob McGwier rwmcgwier at gmail.com
Mon Nov 30 04:20:33 PST 2009

Do you have a 70 cm source of any type that you can use downrange to 
prove that the system is working?  That is,  all together as a complete 
system.  If you can drive the source away until it is demonstrably 
weakening,  then you can test the beam pattern, etc.  If the preamp 
front end is hooked to a dummy load (non functioning antenna system in 
front of it),  then the noise from the dummy load will increase.  You 
need an external source.


Michael Tondee wrote:
> Andrew,
>  I definitely can heart an increase in noise when I power up the preamp 
> and also see an S-meter response. Unfortunately I have absolutely no 
> terrestrial repeaters within my range on 70cm. I've never been able to 
> get into one  even back in the days when I had my TS-2000X. Never been 
> able to hear them either. Checked the preamp cables to make sure they 
> weren't backwards also.
>  In reference to some questions from others I've had, I am compensating 
> for doppler on receive and I've checked all my cables except for the 40 
> foot piece of LMR 400 for open or short with an ohmmeter.
>  Just for giggles I decided to see if  I could copy NOAA weather on 162 
> Mhz band and I can. Don't know if that means anything. I will check my 
> antenna pointing. Getting an accurate fix on true north has sort of been 
> my achilles heel before but I've managed.There is not that much 
> declination here. When I did happen to pick up the brief SO-50 
> transmission last night the rotator was making a fairly large change in 
> Azimuth though. I may just whip up a quick little groundplane to give me 
> a baseline as someone suggested also.
> Thanks for all the responses I've gotten so far.
> Michael

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