W076/M452 replacement cards

From: Mike Cukr <cukr_at_massnet1.net>
Date: Tue Dec 2 19:19:00 2003

> Hmm. I am going by "Figure 5-7 Teletype Connections", which led me to
> expect Relay+ to be connected to the relay, and to the cathode of a diode.
> I expected Relay- to be connected to the anode, and also to a resistor,
> which connects to the other side of the relay. It shows a capacitor
across
> the relay contacts, which also connect to the local switch and the reader
> solenoid.
>
> I don't suppose I could prevail upon you to trace the
connections/schematic
> for me?
>
> Thanks!
>
> Vince
>
>
It was just as you describe except the capacitor is a MOV on mine,
except there was a 10mf cap across the relay coil, that micht have
been a non-DEC FCO and from tha soldering job I know who did
it. The relay is a reed relay marked as 12vdc coil and measured
328 ohms which works out to about 37ma. BTW the run relay
is mounted on a small PCB mounted vertically near the left end
of the keyboard assy. There are four wires that run back into the
rats nest at the rear of the PS.

Mike
Received on Tue Dec 02 2003 - 19:19:00 GMT