The PHILCO Phorum

Hi Guys,


I have an interesting problem this time. I Did a full recap on this AM/FM radio, along with a complete tube and resistor check. I got it all together and had it up in the kitchen where I've been listening to it for a couple weeks. I was listening to it the other day when all of a sudden the volume dropped and I had no sound on either band. Well, back to the bench. I plugged my iphone and was able to hear it just fine. Put the band switch back to AM or FM and nothing.
The weird thing is that one resistor-R16 a 1K, was starting to smoke. I swapped out the 6X5 but it didn't help. I retested all connections and they all look good. Any ideas? (35WG and 25WG)

Either the tube 68A6 or C19 cap, 5000mmf connected to that resistor, SG of the tube and output xfmr

(12-09-2016, 04:22 PM)Eric Adams Wrote: [ -> ]Hi Guys,


I have an interesting problem this time. I Did a full recap on this AM/FM radio, along with a complete tube and resistor check. I got it all together and had it up in the kitchen where I've been listening to it for a couple weeks. I was listening to it the other day when all of a sudden the volume dropped and I had no sound on either band. Well, back to the bench. I plugged my iphone and was able to hear it just fine. Put the band switch back to AM or FM and nothing.
The weird thing is that one resistor-R16 a 1K, was starting to smoke. I swapped out the 6X5 but it didn't help. I retested all connections and they all look good. Any ideas? (35WG and 25WG)

Check for shorts to the chassis around L-13 and bad C-19.

GL

OK, here's what I did. I tested the cap, IF trans and resistor. They all tested good, each one was removed from the circuit for testing. So I put it all together and with all tubes out except the 6X5 (the way I ran all tests). I ran up the voltage slowly, watching the resistor in question for any smoke. Got it up to about 110v with no smoke or heat. After about a minute of this there was a spark under the area of the tuning cap. No smoke or flame (Wow, I sound like kirk). I figured I can't hurt it anymore so I killed the power and installed the tubes. I ran the power up and after a few minutes the radio was working fine. No, I haven't checked where the spark came from, but I will. Thanks to everyone for your help.