Skip to main content

QG, The "electronics" of those old pw whistles was a relay which would pull in in the presence of direct current, or an unbalanced AC.  A makeshift controller was to put a carbon-zinc D cell into the track circuit, which would mean half the sine wave was 3 volts higher than the other half, and this would trigger the relay.  Only sine waves were available from the PW & pre-war transformers.

Add Reply

Post
OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
330-757-3020

www.ogaugerr.com
×
×
×
×
Link copied to your clipboard.
×
×