02-28-2026, 05:10 PM
Still ironing out the bugs here. I did not notice right away but after I fixed the hum problem the shadow meter is not working correctly. It will close up when I tune in a station but when I move off station it takes around 10 seconds or more to spread out. I call this being lazy response. I decided to do some volt checks on the 75 tube. Well the plate voltage is supposed to be 188 but it is 260 volts. I changed 75 tubes several times with no change. So I decided to see if I could reduce the plate voltage by changing the 70k (#59A). I got the voltage down to 190 by using a 560k resistor. Yeah I know this is not the way to do it but it also resulted in my better sounding radio. I redid the alignment to see if that would help the lazy meter but no go. All the other tubes are close to what they should be. I'm using a VTVM.
Also when tuned off station it is quiet but gets noisy as you would expect when tuned off station. As the noise increases so does the meter spread out. AVC voltage changed immediately.
Any ideas?
Also when tuned off station it is quiet but gets noisy as you would expect when tuned off station. As the noise increases so does the meter spread out. AVC voltage changed immediately.
Any ideas?




