08-29-2017, 07:25 PM
Well. Let's just say that the person who recapped the radio had very approximate idea as to the how to connect electrolytics and other things.
First, as I wrote before, the lytics were not according to the schematic. More to this, the wire colors were preserved, so why not do it right, right?
I reconnected the caps, plus I used some higher voltage caps with better ripple rating, as I think 160V is a bit low....though it is a half-wave, but they looked flimsy and so I reserved them for other uses....for someone who inherits them after I die: some noname small jobs they were.
Anyways, after the power-up the hum went away and the radio is receiving across the dial. My local station's music is garbled but the speech in other stations is ok. Maybe the AVC is not working properly, maybe....who knows.
As the radio was playing, I gave it a sniff, as I usually do, and felt some light smell coming from the bottom; I turned it over and the 50 ohm resistor across the 25Z5 plates was very warm, almost hot, which it shouldn't be. Then I realised the guy soldered the diode that supplies the filaments after the resistor, so it conducts extra....0.3A, which is way more than it should, resulting in extra....4.5W dissipation. I moved the diode where it should be, right to the AC input before the resistor, and the heating stopped.
Tomorrow I will try to find out why the local station is garbled and maybe align the ugly creature.
First, as I wrote before, the lytics were not according to the schematic. More to this, the wire colors were preserved, so why not do it right, right?
I reconnected the caps, plus I used some higher voltage caps with better ripple rating, as I think 160V is a bit low....though it is a half-wave, but they looked flimsy and so I reserved them for other uses....for someone who inherits them after I die: some noname small jobs they were.
Anyways, after the power-up the hum went away and the radio is receiving across the dial. My local station's music is garbled but the speech in other stations is ok. Maybe the AVC is not working properly, maybe....who knows.
As the radio was playing, I gave it a sniff, as I usually do, and felt some light smell coming from the bottom; I turned it over and the 50 ohm resistor across the 25Z5 plates was very warm, almost hot, which it shouldn't be. Then I realised the guy soldered the diode that supplies the filaments after the resistor, so it conducts extra....0.3A, which is way more than it should, resulting in extra....4.5W dissipation. I moved the diode where it should be, right to the AC input before the resistor, and the heating stopped.
Tomorrow I will try to find out why the local station is garbled and maybe align the ugly creature.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
