Philco 19H weak/no reception - Printable Version
+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: Philco 19H weak/no reception (/showthread.php?tid=11409)
+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: Philco 19H weak/no reception (/showthread.php?tid=11409)
Pages:
1
2
RE: Philco 19H weak/no reception - jeffb - 01-15-2015
Hello, changing to a 10k didn't work. Actually I put a pot in there and had it all over to see if I could find its sweet spot, no luck. I will try a different tube. I did see there is a 36A in the set vs. a 36, I see it is a suitable sub, anyone have any experience with that? Thanks for the help!
RE: Philco 19H weak/no reception - morzh - 01-15-2015
Could be a weak tube, for oscillators it could be criical...
RE: Philco 19H weak/no reception - jeffb - 01-15-2015
I'm hoping that is it I will post the results I hope to find a 36 tube and not a 36a.
RE: Philco 19H weak/no reception - jeffb - 01-18-2015
Hi everyone, great news! The radio is alive and well. I tried 2 different good tubes and went with the one that worked best. However, either of the two good tubes did not like lowering the oscillator resistor down to 10kohms, so I left the 15k in there. I actually put a pot in the circuit to find its "sweet spot" with both tubes and it liked the 15 k ohms best. I don't care, it works great now, now to add the MP3/ I pod jack so I can listen to old radio shows. I put in the 1/8" audio jack on the ungrounded end of the volume control. It works, but there is some bleedthrough from the am dial. I built an audio isolation transformer from the Radio Shack plans ( I forget where I saw that) but need an adapter to go from the rca jack to the 1/8" audio. Thanks to all for your help here. PS- I just bought another Philco 19 cathedral yesterday!! That one is now on my long list!!
RE: Philco 19H weak/no reception - morzh - 01-18-2015
Two Philco 19 make for one 38.
RE: Philco 19H weak/no reception - PAradiogeek - 01-19-2015
+1 on Ron's comment on lowering the cathode resistor value. I fixed up a 19B about a year ago. At the time I put a 10K resistor there. Last week I powered it up and tried tuning to a station at 610. However, all sound stopped as soon as the dial went below about 720. I tried another 36 tube, but that didn't really help.
I remembered seeing other posts where Ron said that this resistor could be as low as 7500 ohms, so I tried it and it worked great.
Thanks Ron!
RE: Philco 19H weak/no reception - Arran - 01-20-2015
(01-18-2015, 05:51 PM)jeffb Wrote: Hi everyone, great news! The radio is alive and well. I tried 2 different good tubes and went with the one that worked best. However, either of the two good tubes did not like lowering the oscillator resistor down to 10kohms, so I left the 15k in there. I actually put a pot in the circuit to find its "sweet spot" with both tubes and it liked the 15 k ohms best. I don't care, it works great now, now to add the MP3/ I pod jack so I can listen to old radio shows. I put in the 1/8" audio jack on the ungrounded end of the volume control. It works, but there is some bleedthrough from the am dial. I built an audio isolation transformer from the Radio Shack plans ( I forget where I saw that) but need an adapter to go from the rca jack to the 1/8" audio. Thanks to all for your help here. PS- I just bought another Philco 19 cathedral yesterday!! That one is now on my long list!!
I would avoid adding an RCA jack to any radio that did not have one, especially a Philco, every time I see one that someone else added to a radio I remove them since they usually cause nothing but trouble. In order to make one work without AM radio bleeding through you will need to kill the signal coming from the front end with a switch, then you have to worry about routing the cable correctly, and using shielding, and trying to get impedances to match, and this is if it uses a normal volume control with the input going to the grid of the first audio tube. If you want to avoid impedance matching problems, or having to work around archaic volume control circuitry, get an SSTRAN transmitter kit, then you can broadcast your music to an AM radio in the house, no holes, no evil RCA jacks, and no butchered wiring.
Regards
Arran
RE: Philco 19H weak/no reception - jeffb - 01-20-2015
Hi, thanks for the SSTRAN kit advice, I will keep my eyes out for one.