[GreenKeys] Model 28 ASR short on current loop interface.

[Duncan Brown]

Charlie,

Some units will put a short on the line when the power is off to the unit.

Good luck,

Duncan
K2OEQ


On 4/20/2026 6:25 PM, Charlie Beck via GreenKeys wrote:
> Hello,
>
> I have a model 28 ASR wired in half duplex. I had been successfully 
> using it with an interface I am building until it stopped operating. I 
> measured the resistance of the loop and it's a dead short. After 
> unpluging evreything from the Electrical Service Unit there is still a 
> short on the loop. I checked the coils and they are not shorted. I am 
> not very knowledgeable on the workings oif these machines apart from 
> the basics. Is there anything that come to mind that might be the 
> source of my problem?
>
> Thanks,
> Charlie Beck
>
> ______________________________________________________________
> 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 toduncanancy at earthlink.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20260420/12d4d9c1/attachment.html>