[GreenKeys] ID Relay 35 ASR

[Ralph Irish]

Hi guys 

The 101A and 101C both had wire spring relays in them. The mounting plate had a few spare holes to 
add more. A friend of mine did some mods on his 101A which required two relays. It was fortunate 
that the AK4 Relay had two units on a single frame, and the contact arrangement was such that they 
worked just fine. 

His 'mod' was to be able to use the Data Set with his Model 28KSR on the Detroit area "Telex"** 
system, without having a separate phone line but still have his machine respond to 'data calls' while 
'voice calls' would also go through. Sounds confusing, I know. 

He put in a few PUT timers (PUT = Programmable UniJunction Transistor) so that this would all work 
for him. One would call his number for a 'data call', allow one ring, then hang up. Immediately dial 
the number again. If the second ring came through MORE than six or seven seconds later, but 
BEFORE 20 or 30 seconds, the Data Set would respond, pull the line into service and turn on the Teletype 
for a data call. If the second ring came in in the normal time, the 'ring' would be passed to the phones 
in his house. He had the phones set so that all 'first rings' were suppressed, and the phone's bells 
remained quiet until a legitimate voice call came in. 

Later on, during the IC development period, he would have probably used a couple of 555 timers or 
maybe a 556, which was two 555s in one package. 

73, 

Ralph 

** This amounted to about 20 people with a spare teletype in their home 
and access to a 101A or 101C Data Set. It was all informal and a big 
thorn in the side of Michigan Bell. They could not stop this from 
happening with their 'foreign attachment' rule. The Data Sets were 
all designed and built by Western Electric to meet the Bell System's 
requirements. 

- - - - - - - - 

From: "WAYNE" <teletypeparts at comcast.net> 
To: "Ralph Irish" <w8roi at wowway.com>, "Ken Wiebe" <me at networkguy.com> 
Cc: "Thomas Tillson via GreenKeys" <greenkeys at mailman.qth.net> 
Sent: Monday, June 10, 2019 11:33:19 AM 
Subject: Re: [GreenKeys] ID Relay 35 ASR 



Those relays look the same as the ones in a Western Electric 101-C modem. 




More useless comments but maybe it will help. 




73, 




Wayne 

KB1FDW 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20190610/0ff681f4/attachment.html>