[GreenKeys] M28 ASR full duplex?

[Jeffrey Golas]

On the NJ, each model 28 actually has 4 loop connections. Now they were wired as low level, but looking at the panel the keyboard, printer, and TDS were all seperate loops so definitely possible to do full duplex. In the low level ESA, there was a jumper wire for having the printer in line with the keyboard.

On the converters, yes they have seperate input and output, but the manuals say you can just jumper across the plugs for a half duplex arrangement.

Other than the drive I spent all day today inside a 28. I smell like a 28. I think I can taste it too. Not as good as it smells LOL.

It took me waay longer than I expected to splice a bunch of wiring back together, and Im way more sore than I expected lol. (I had to fix some AC wiring in the base).

Jeff KC3GJX

-------------- next part --------------
A non-text attachment was scrubbed...
Name: image0.jpeg
Type: image/jpeg
Size: 128275 bytes
Desc: not available
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20230408/89cab8de/attachment.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image1.jpeg
Type: image/jpeg
Size: 164996 bytes
Desc: not available
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20230408/89cab8de/attachment-0001.jpeg>
-------------- next part --------------




> On Apr 8, 2023, at 2:02 PM, Duncan Brown <duncanancy at earthlink.net> wrote:
> 
> ?I'm mainly a Kleinschmidt guy, and I have never had to dig into the M28 wiring before.  Other than change a couple of motor-start capacitors, my M28s have just run.
> 
> But now that I am getting into this M28 ASR wiring for our TMC station, it looks like the M28 (especially the AN/UGC-6) was mainly used with TX & RX in just one loop.
> 
> Was the M28 ever used in full-duplex (separate TX & RX loops)?
> 
> Ham TUs like HAl & Dovetron would take one loop and separate the TX & RX signals.  But what about military units like the CV-2460?  Just looking at the manual, it looks like it needs separate TX & RX connections from the TTY, but the UGC-6 does not seem to offer that option. (At least not from looking at the UGC-6 schematic, Fig 12-38.)
> 
> From the Teletype Corp. schematics, I can see that the M28 ASR has very flexible wiring and you could bring out the keyboard contacts separately.  But I'm surprised that the UGC-6 schematic doesn't show that option. Or is there another schematic to show separate TX &RX wiring?
> 
> Thanks,
> 
> Duncan
> K2OEQ
> 
> 
> 
> ______________________________________________________________
> 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 jeffg at junknet.net