Posts: 11
Threads: 6
Joined: Feb 2022
City: Prospect
State, Province, Country: CT
Hello Everyone,
I have a few more questions on my Philco 84 restoration. Does anyone know where I can obtain the values for the antenna, oscillator, IF, and power transformers? I have a good schematic and parts list but those values aren't shown. I am going to replace all the caps and most of the resistors and don't want to run into any issues with the transformers because I am sure they are hard to get or rewind. I have an old Philco 60 chassis but don't know if some of those parts would be similar.
Regards,
Bob
Posts: 1,032
Threads: 9
Joined: Jul 2020
City: Greenlawn
State, Province, Country: NY
Hi CT Kid,
Yes, the resistances are not listed on the schematic for the 84, but they are listed on the 81, which is an older version of the 84, the big difference is that the 81 receives the "Police" band (180 meters?) Otherwise the resistance reading for the coils should be close. The big problem are the tickler coil for the Oscillator and the primaries for the antenna coil and the "IF coil" that feeds the 2nd detector. There are several articles on rewinding these primaries. Not horribly difficult.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
Best Regards,
MrFixr55
Posts: 7,285
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Don't think there are any rf/if parts on the 60 that are interchangeable w/the 84. Both osc coils are prone the have bad primaries so it makes sense to rewind the proper one. The 60 is a two band set where the 84 is a mono band set. There's no feedback tap on the (60) IF transformer so the original regeneration circuit won't work.
Generally speaking all of the rf/if coils should read <100 ohms, opt 400 ohms, and hv secondary 600 ohms end to end. Bear in mind these are all rough numbers. The true test is the measure the ac voltage from the ct to each end and it should be pretty equal +/- a couple of volts. Anything that measures in the 1000's of ohms is bad/open.
https://philcoradio.com/library/download...%20178.pdf
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
(This post was last modified: 10-17-2024, 01:14 PM by
Radioroslyn.)