[GreenKeys] Navy Teletype Message Generator

[Gillian Webb]

Nifty! I found the original plans this appears to be built from, or at
least a very similar "solid state fox box" circuit, on page 30 of the
November 20, 1976 issue of Ham Radio Magazine:

https://archive.org/download/hamradiomag/ham_radio_magazine/Ham%20Radio%20Magazine%201976/11%20November%201976.pdf

What's the info printed on that white chip? I agree it looks like they
"adapted" something in - thinking a comparison to this reference design
could shed light on this.


Cheers,
Gillian

On Tue, Jan 24, 2023, 9:42 AM Jeffrey Golas <jeffg at junknet.net> wrote:

> Thought you guys and gals might find this interesting...I volunteer on
> Battleship NJ and found this tucked away. Appears to be Navy-like but
> mentions "project" on it, serial #3 lol. Other than WMS on the board theres
> no manufacturer.
>
> Its a RTTY/Teletype message generator that does the "quick brown fox"
> message. Whats really interesting is that all that is based on ONE chip
> whose sole purpose is exactly that. A MM5220DF. Other chips in that series
> have similar purposes, like ASCII-BAUDOT conversion.
>
> Theres what looks like a white CPU, but Icant find any docs on it. It
> almost looks like something they had a surplus of, and with no rom,
> possibly wired it as a NOP (no-operation) so that it would just be an 8 bit
> counter. I think anyway.
>
> It does seen to work after cleaning all the switches, I plan to test on
> the loop. All it does is keying via a solid state relay. I tried piping my
> signal gen through it but Fldigi couldnt decode.
>
>
>
>
> Jeff KC3GJX
>
> ______________________________________________________________
> 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
>
> >>> Jordan Spencer Cunningham's GreenKeys Search Tool:
> https://teletype.net/gksearch
> >>> 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
> Message delivered to thaeli at magfest.org
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20230124/9254607a/attachment.html>