The PHILCO Phorum
46-1226 code 122 no am or shortwave good phono,, i fixed it - 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: 46-1226 code 122 no am or shortwave good phono,, i fixed it (/showthread.php?tid=3040)


46-1226 code 122 no am or shortwave good phono,, i fixed it - jstaf40 - 03-12-2011

hope you can help i have a 46-1226 code 122 i replaced all caps and resis including electrolytic, the radio did not work when i bought it the voltage are 25v high on the 3 test sites on the electrolytic the phono works OK all tubs are good i have run out of things to ck
i am new at this is my first one can you give me a hint on what to look for
thanks
john

Re: 46-1226 code 122 no am or shortwave good phono - Radioroslyn - 03-12-2011

Hi John,
Took a quick look at the diagram of your set and you have a lot of possibilities for it not to work! I think the easiest way is to do some troubleshooting on each stage of the set to see what is or isn't working. You said that the phono is working so we can probably rule out the audio stages as a problem.
The next thing to check is the IF and detector stages. What you will need to do this is a signal generator. Can be an older analog job. Do you have one?
Terry

Re: 46-1226 code 122 no am or shortwave good phono - Chuck Schwark - 03-14-2011

Dirty/tarnished bandswitch contacts are highly like to be part of the problem, besides a possible open coil(s).

Chuck

Re: 46-1226 code 122 no am or shortwave good phono - jstaf40 - 03-14-2011

thanks guys for your help i have ck with a sig gen and section 1 the voltage is 25v high it could be my old meter i ordered a new one ,section 2 3, i think are OK 4 i think is where the problems are this has the 7af7 tube and to get to the cap & resis you have to lift the rotary up and out,the rotary has been cleaned all seem to be OK SW is very faint signal when i got the unit it had a burnt out look like a 1/2 watt resistor on pin 2&7 on 7af7 i have not replaced same can not find on any paper work. when i run the Sig gen i find it works at 455 herts but when i move the dial it tapers off i thank i fried my brain i have tried to find a local repair shop to no a vale,how do you test the SW & AM coils and trimmers in section 4
i hope this make since most of the radios i have worked on were in working condition so replacing cap and such were easy this was dead from the start
thank you all for your help
john

Re: 46-1226 code 122 no am or shortwave good phono - Radioroslyn - 03-14-2011

I did a little looking around pins 2 and 7 are the cathodes the two triode in the 7AF7. If I use the diagram for the 121 model one of the cathodes ( the amp side) is tied to ground though a 2.2K resistor. If it is open you will have a high voltage on the cathode and the set won't work.
Did you order the service info from Chuck? That should have the data for the resistor and the voltage measurement. Is your local oscillator working?
Terry

Re: 46-1226 code 122 no am or shortwave good phono - jstaf40 - 03-15-2011

terry
thank you for reply i ran test on the OSCILLATOR and got a minus voltage on pin 5 of 1-2 volts minus and also ck pin 7 for the 2.200 resistor and its new as all caps and resistors,,, i have very faint signal at 1500 hrts but that's it i am not picking up Sig gen signal on SW any other help would be of great help
thanks again
john

Re: 46-1226 code 122 no am or shortwave good phono - Radioroslyn - 03-15-2011

Well - voltage on the grid is a good thing but to double check the osc set the bandswitch for the bc band. Tune the dial to 1000kc. Use a transistor radio near the 7af7. Tune it to 1000kc + the IF frequency 455kc. 1455kc. If the LO is running you will hear a loud hum in the transistor radio. If the tuning isn't dead on on the Philco you may need to adjust it's frequency bit to hear the LO (local oscillator)
Terry

Re: 46-1226 code 122 no am or shortwave good phono - jstaf40 - 03-15-2011

I found out what was wrong it was ME i put a CAP & resister 1 pin over, never work on a radio then you are tired, i want to thank all of you that helped with this project it was a labor of love and it finally WORKS
thanks again
john

Re: 46-1226 code 122 no am or shortwave good phono,, i fixed - Radioroslyn - 03-16-2011

Glad to hear your up and running!
Terry