[Milsurplus] aircraft transmitter & dynamotor

[Morrow, Michael A.]

I wrote:

> Resistor 143 in the TM-AH-172 junction box is about 10 ohms...in
> series with the dynamotor unit's choke-filtered B+ output, which
> junction box TR relay 153 switches to either supply B+ to the all
> receiver stages except audio output, or supply B+ to all transmitter
> stages.
>
> I forget what the manual says the function of resistor 143 is, but it
> can't really be all that essential.

I checked my SCR-AL-183 manual last night.  It states that resistor 143
is a "damping resistor" used to reduce sparking at the contacts of relay
153.

Mike / KK5F