The PHILCO Phorum
Another Cantankerous 89-123 - 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: Another Cantankerous 89-123 (/showthread.php?tid=14206)


Another Cantankerous 89-123 - Hugh C - 03-12-2016

Hi I have been browsing for some time. Starting an 89–123 ( I think as no tags on it). That the recap went with absolutely no problems but could not pull in stations. Pulled out my old signal generator and found that the IF frequency would blast through it with no problem. I thought I had it made. Boy was I wrong. I found that the oscillator tickler coil  was open so rewound the coil put it back  in. It made some squeals and some other funny noises and then all of a sudden it went quiet . Voltage  checked  indicated that the B+ was very high. I replaced about 8 resistors that were way out of tolerance. Still nothing so got disgusted and slid it over to the edge of the bench.

Pulled out an 98-121 and recapped. Went well with no problems and after alignment pulled in local stations. The next thing I know smoke start rolling out of a dual capacitor that someone had replaced the original ones with. Scabed in a couple of 10 µF and the radio works fine. I wish I had a couple of the old original cans to re stuff.

I went back to work  on the123 for several days but couldn't make anything work. A little angel taped on my shoulder and told me to spray some tuner spray cleaner lubricant on the pins of the tubes and wiggle them around in the socket. Lo and behold the B+ dropped to normal and some weird sound started out of the speaker. You know squeals and other noises. So that's where I set is now who would've thought  that the tube sockets were not be making contact. Anyone have some good advice on how to clean tube sockets?

Tomorrow I'll get out the scope and see if I can figure out if the oscillator is working properly and try to find where the weird noises are coming from.

Any advice for an old man (85) would be appreciated.

RE: Another Cantankerous 89-123 - klondike98 - 03-12-2016

Welcome to the Phorum!
Icon_wave

RE: Another Cantankerous 89-123 - Radioroslyn - 03-12-2016

Hi Hugh and welcome to the Phorum,

> Anyone have some good advice on how to clean tube sockets?

Deoxit works well for me, just  make sure that it is dry out before powering the set up.

>Tomorrow I'll get out the scope and see if I can figure out if the oscillator is working properly

You can listen to it in another receiver tuned to the same frequency + the IF frequency. You can use a transistor set placed near the osc tube.

Glad to have you aboard!
Terry

RE: Another Cantankerous 89-123 - Mondial - 03-12-2016

You can also try re-tensioning the tube socket contacts. Sometimes the metal contacts lose their spring tension and fail to grip the tube pins tightly. If the tube pulls out of the socket easily with little effort, the contacts are probably loose. After removing the tube, carefully squeeze each contact with needle nose pliers so that tension is restored.

Make sure all the tube shields are in place when you test the radio. The grid lead of the 75 audio stage is right near the 42 output tube and stray coupling can cause the circuit to oscillate and squeal, especially when the volume control is turned up.

RE: Another Cantankerous 89-123 - Steve Davis - 03-12-2016

Also, make sure the grid lead on the 75 is routed on the inside of the tube shield. If not, this will cause squeals and howls.

Steve

RE: Another Cantankerous 89-123 - Hugh C - 03-13-2016

Icon_angel I followed the directions for rewinding the tickler coil to the letter but I tried switching terminals 1&2 and now the radio lives again.

RE: Another Cantankerous 89-123 - Hugh C - 03-17-2016

Icon_angel I followed the directions for rewinding the tickler coil to the letter but I tried switching terminals 1&2 and now the radio lives again.

RE: Another Cantankerous 89-123 - markmokris - 03-17-2016

So it is working, and you are pulling in stations? All across the bands?

Mark K8KZ