[amsat-bb] FM Squelch blocks everything!

Roger ai7rogerroger at gmail.com
Fri Feb 3 14:37:38 UTC 2017


Sounds like it's time to clip the lead on that guy and deposit it in
circular file.!


73, Roger
W7TZ
CN83ia

On Fri, Feb 3, 2017 at 5:57 AM, Robert Bruninga <bruninga at usna.edu> wrote:

> Fired up our next PSK31 cubesat card for first test and the ground station
> got full S9 carrier but signal was full of noise totally masking the PSK31
> tones.
>
>
>
> Turned off.  Channel was clear. Then opened squelch and there was S9 noise
> over 5 Mhz around our UHF downlink.
>
> Went down the  halls with HT and signal tapered slowly down in all
> directions.
>
>
>
> Came back and with 1” of wire in the HT antenna connector narrowed it down
> to a cheap battery charger.
>
>
>
> Lesson over and over again, is that a squelch HIDES everything  Even 20+S9
> noise sources.  Zero bars while squelched.
>
>
>
> Reminded me of when we had local repeater problems.  Turns out it was the
> megawatt balloon radar operating in VHF looking over Washington DC.  No one
> could hear it with their radio squelched.  But open the squelch and every
> channel throughout 2m would show 60+S9 bars on the noisy trash.
>
>
>
> It was similarly baffling at the peak of packet in the 90’s when some hams
> would complain that their packet system wasn’t working, and yet they never
> turned up the volume to listen by ear to the channel to see what was going
> on.  I still see that sometimes in our students who think that all you have
> to do is hook-up two wireless thingy’s and is should just work… but never
> think to listen to a channel or use a spectrum analyzer to see what they
> are dealing with.
>
>
>
> Turns out, this battery charger (now that I remember) was the SAME one that
> got me several years ago.  I was just too old to remember until I had again
> done the full DF search through the entire academic building and ended up
> right back at the same point.
>
>
>
> The older we get the more we have to learn over and over again ;-)
>
> Bob, WB4APR
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
>


More information about the AMSAT-BB mailing list