The AM Forum
March 28, 2024, 08:00:17 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: HQ 170 CW sidetone monitor  (Read 1252 times)
0 Members and 1 Guest are viewing this topic.
ns7h
Member

Offline Offline

Posts: 45


« on: April 10, 2019, 11:03:07 PM »

Has anyone modified an HQ 170 so that when it is muted, a sidetone signal is still enabled?  My "Elmer" made a change to my receiver in the 1960's that provided a sidetone with muting.  Lots of time has passed - and I have forgotten as much as I knew at the time as to what was done.  Forward 55 years later and a different receiver.   I have a fairly stock HQ 170 paired with a Heathkit Apache.  The antenna to the receiver is bypassed during transmit using the classic Dow Key relay and the accessory contacts cut regulated voltage to the screens of the first several stages RF-IF in the receiver.  Would reducing this voltage instead of interrupting this via the relay provide usable signals to sidetone levels without damaging the receiver?  Would a series resistance instead of open circuit  across the mute terminals allow some signal for sidetone?  It seems this would have been a common modification but I cannot find one in a reasonable search.  Also, my retired brain was never a good tube/signal analysis guy.

Thanks, NS7H
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.03 seconds with 18 queries.