[GreenKeys] FRF FSK conv. (was - Two eBay Novelties)

[Duncan Brown]

David,

Yes, that sounds like the AFSAV-133 (aka AN/FRA-86).  You can see the 
manual at 
http://www.nj7p.info/Common/Manuals/PDFs/Military/AFSAV%20133D%20Feb%2062%20NJ7P%20AS.pdf

And Nick has info on his http://www.navy-radio.com/ site.

We had 4 or 5 of them at the 370th ASA Co at Ft. bragg in 1968-70, but I 
never heard any DFSK signals on them.

I assume that you do not have any of them any more??

I've been looking for one for the AWA Museum.

Duncan
K2OEQ

On 09-Feb-14 21:00, David Burns wrote:
> On 2/9/2014 8:12 PM, Nick England wrote:
>> This "dual channel" FRF unit is just dual diversity....The FRF wasn't 
>> an intercept
>> unit.
> Indeed, dual diversity.  I wasn't suggesting it was an intercept unit, 
> but yes, diversity and not analogous to the Russian system.
>> I believe the Soviet system you are thinking of was DFSK running two
>> different TTY signals on a pair of frequencies.
> The NSA units I had decoded four audio frequencies each separated 
> (from the next lower) by a standard shift (determined by a plug-in 
> filter group encased in a metal can about the size of a TV B+ 
> capacitor with an octal plug on one end of the assembly), and when 
> both channels were running the scope presented a square pattern. (As I 
> recall, I only saw that once.)  It had a plug-board (associated with 
> the filter plug-in) to allow for dynamically assigning M-M, M-S, S-M 
> and S-S to different frequencies.  My NSA buddy said it didn't take 
> long to determine the correct mark-space frequency assignments once a 
> transmission started.  I only used the standard 850 shift 
> single-channel decoding.  It was a single monolithic unit (scope, 
> power supply, decoding logic, filters) about two feet tall in the 
> rack.  I think I had 5 or 6 of them, and two that worked (using about 
> $100 in tubes [each] at the time.)  It output keyed tones for each 
> channel.
> ______________________________________________________________
> GreenKeys mailing list
> Home: http://mailman.qth.net/mailman/listinfo/greenkeys
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:GreenKeys at mailman.qth.net
>
> 2002-to-present greenkeys archive: 
> http://mailman.qth.net/pipermail/greenkeys/
> 1998-to-2001 greenkeys archive: 
> http://mailman.qth.net/archive/greenkeys/greenkeys.html
> Randy Guttery's 2001-to-2009 GreenKeys Search Tool: 
> http://comcents.com/tty/greenkeyssearch.html
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>


---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com