Hello guy's
I have this Philco 89-123 up and running, replaced all cap's, and a couple of resistors. My issue is that the voltages are high. With 115 ac going in the radio, this is what I have
Tube 80 has good voltages
" 42 P is 41 high, S is 50 volts high
" 77 P is 34 volts high, S 35 volts high, K is 14 volts high
" 44 RF P is 36 volts high, S is 36 volts high, K is 13 volts high
" 44 IF P is 50 volts high, S is 38 volts high, k is 14 volts high
What to do...............
Jim
First things first, are you measuring by a contemporary DMM while reading the expected voltages from the original document? Because they will be high thenn.
Morzh, yes I am thank you for the reply.
I have a defective 77 tube if I tap it the signal comes and goes except the high end freq. I tried a 6C6 and A 57 supposed subs, could not receive at all with those, unless there is some that needs to be done when swapping these tubes.
I will be looking for a 77.
You might try a 78 tube. 6C6/6D6 for 77 or 78's haven't worked for me at all. The 57 has a 2.5v heater vs 6.3 of the other.
I doubt that a 78 tube will work in this application, since the 77 is used as an autodyne converter and oscillator.
Like Terry, in my experience a 6C6 does not work for a 77, nor a 6D6 for a 78, nor vice versa.
As as Terry said, the 57 has a 2.5V heater and the heater string in model 89 is 6.3V. Not to mention the 57's heater draws more current.
Thanks guys, I have a 77 tube on order.
Check for shorts in the speaker field coil? I also had a Gloritone with a weak '45. All the plate and screen voltages were high throughout the radio. When I replaced the '45, everything went back to normal (about 250V for the B+ to the output transformer). Is your '42 good?
I know that modern DMMs have much higher input resistance than the 1000 Ohm per Volt meters of yore, but I don't think that an old 1000 Ohm per Volt meter would load down the plate and screen voltages of the output tube that much when compared to a modern DMM. Other measurements, all bets are off.
Alignment on the Philco 89, IF alignment, does the signal generator lead to the 44 IF tube go on the G1 cap. Also does the generator lead go to the top of the 77 without the clip in place. The rest is clear.
For IF alignment - remove grid cap connector from the 77 (or 36, depending on which version of the 89 you have) and feed the signal generator output to the grid cap of the 77 (or 36) tube. Negative lead of the signal generator to chassis. Align the IF trimmers at 260 kc.
For RF alignment - Reconnect the grid cap connector to the 77 tube, and connect the signal generator output through a 200 pF capacitor to the set's antenna clip. Again, the negative lead of the generator goes to the chassis.
The complete alignment procedure may be found on page 14 of the book
Aligning Philco Receivers by John F. Rider.
https://worldradiohistory.com/BOOKSHELF-...s-1937.pdf
Good luck.
Thank you Ron......................
Well, I tried. I replaced all caps and resistors. Rewound the OSC tickler (cathode), cleaned the tuner new bushings. I did the alignment according to J. Rider book. Had a hard time with it lots of noise and whistling. Tuning the low freq. was the worst. What I ended up with two stations 1200kHz and above. Lower was all squealing, thumping and motorboating. Ron's thread about the Philco 89 from h**l described it well, mine was just like that.
I just don't have the wire and the expertise to rewind the OSC coil. I am contemplating what to do. I read several threads on this radio all the problems tend to be the coils. I saw that you should bake them to drive out the moisture.
Someone could make a pretty penny selling rewound Philco coils or selling a conversion kit for a 6A7 Pentagrid Convertor for the 89 and similar units with an autodyne 1st Detector.
I only had one other Autodyne, an 80 Jr. I was able to repair the open in the tickler without a complete rewind. I dunno why the 89 gives me so many fits.
Taking another stab the next time it rains on LI. It has been very dry here to the point where the Water District imposed odd - even watering.
I have an OSC coil coming, we shall see.
MrFixr55 thanks for the reply.
Hello guy's
On this radio tube #77 has a strap between pin 4 & 5, I don't see this on the schematic.
Pin 4 shows ground and pin 5 goes to the tickler coil on the OSC per the schematic.
Your thoughts