[GreenKeys] New Teletype Model 28 ASR

[William Wuttke]

My “new” 28ASR is functioning very well. I saw that the felts were still wet with oil after 11 years of storage, so I gave it a quick check.

Keyboard, Typing Unit, TD, Keyboard Typing Reperferator (keyboard perforator), Answerback (after replacing a resistor), all work OK.  Still need to check the line reperforator.

It’s got some homebrew mods that I have to sort out. Also need to mod for 20 ma. I found that no schematic available online has a unit wired like mine, or even has some ot the same equipment. My Keyboard Typing Reperforator has a remote operated punch on/off (disabled over the years). The ESU has the Line Shunt Relay, Line/Test switch, Line Relay subchassis without Line Relay or socket, Local loop power supply, and Power entry module. Right now the reperf selector magnets operate in line mode only (homebrew switch). I’d like to be able to use it in local mode as well. It doesn’t look too difficult - I’ve been using colored pencils to trace the signal flow in the Western Electric large schematic.

I’m taking a month-long vacation overseas, so won’t be able to get it “online” until after that.

Thanks to everybody for your help.

Here’s a quick video of initial testing:

https://youtu.be/ACKng7bL0iU <https://youtu.be/ACKng7bL0iU>

73,
Bill Wuttke
KE3BK
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