[ARC5] Re: [Milsurplus] Re: 6m "Golden Era" Radios with Squelch

[jcoward5452 at aol.com]

Dave,
  Kool idea,my read is an upconverter to 75MHz? I had one once labeled 
BC-666.Had pencil tubes but I sold it as the "radio from Hell" due to 
it's numeration.(tongue firmly planted in cheek!).
 Jay KE6PPF


-----Original Message-----
From: David Stinson <arc5 at ix.netcom.com>
To: Old Tube Radios <boatanchors at theporch.com>
Cc: Milsurplus <milsurplus at mailman.qth.net>
Sent: Mon, 19 May 2008 7:24 am
Subject: [Milsurplus] Re: 6m "Golden Era" Radios with Squelch


> ----- Original Message ----- > From: "David M. Upton" 
<david at wb1cmg.mv.com> 
>>I would like to know if any of the classic AM 6m rigs were equipped 
with >>carrier squelch. My recollection is very few if any. This is a 
>>consideration in setting up a monitoring capability on 50.4 MHz .... 
 
I had an idea- though I haven't done it yet- 
of how to put those little 75 MC "marker beacon" receivers to use as 
band-opening alerts. A little NE602 converter would provide 
both gain and conversion. They're wide enough that signals on both 
50.400 and 50.125 would be detected. Or you could use the old 
40-something MC paging channels (don't know if they are still as active 
as they used to be), or channel 2 television carriers, etc. 
Put a whip antenna on the converter and 24 volts to the little unit, 
set the "trip level" and forget it. 
When there's an opening, you'll get a relay closure 
to connect a speaker, flash a light or blare a siren, as you see fit. 
I have a circuit for the converter, which takes 10 parts and a perf 
board. 
The only slightly-expensive part might be the crystal. 
Tuning the set freq of the receiver around 
might allow a surplus xtal to work; the 602 will do 3rd overtones or 
fundamentals, and several harmonics of the xtal freq as well. 
If you're really good and use quality parts, you can wire the 602 with 
a VFO local osc. and skip the crystal. 
 
73 Dave S. 
 
______________________________________________________________ 
Milsurplus mailing list 
Home: http://mailman.qth.net/mailman/listinfo/milsurplus 
Help: http://mailman.qth.net/mmfaq.htm 
Post: mailto:Milsurplus at mailman.qth.net