Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Philco 89 Last Version Dies around 1200 kHz
#2

Hi Mike

Sounds like an oscillator coil problem to me.

You mentioned rewinding the oscillator plate winding...is is usually the oscillator cathode winding that goes bad. (This is the outermost winding.) The turns count, size of wire and direction of winding are all critical. Even though the late version 89 sets use a Type 77 instead of a Type 36, it is still that finicky autodyne circuit that is not inherently stable.

Besides rechecking your windings, I strongly suggest you bake your oscillator coil in an oven at 200 degrees F for about 30 minutes to drive out any residual moisture. Afterward, spray the coil with clear lacquer or coat it with clear nail polish. This will help prevent future moisture absorption.

Of course, for a permanent fix, you could perform my Super 89 Mod by changing the 77 to a 6A7, and re-rewinding the oscillator coil to the specs given in the post linked here. It is far more stable than any autodyne circuit. But, of course, it also destroys the originality of the radio. Just a thought.

--
Ron Ramirez
Ferdinand IN


Messages In This Thread
Re: Philco 89 Last Version Dies around 1200 kHz - by Ron Ramirez - 09-08-2008, 09:59 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Gilfillan Brothers Car Radio?
Hi everyone,  Special thanks to Joe Rossi for tracking down this obscure radio and thanks to others who took up the hun...Antipodal — 08:15 PM
trying to identify this wire type
Here's one source for your wire of many. Take care and BE HEALTHY! Gary P.S. Can't get the right color you need? I ...GarySP — 06:40 PM
trying to identify this wire type
...and modern wire of the appropriate gauges and insulation V-rating (300V minimum, usually shown right on the wire) is ...morzh — 05:47 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
I have a question about this radio, is there anyone that has access to this radio that has an intact unmolested speaker ...captainclock1988 — 04:28 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Well what makes me confuse all of those companies is that all three of those companies (Setchell-Carlson, Stromberg-Carl...captainclock1988 — 04:21 PM
trying to identify this wire type
The red wire is rubber covered wire. The others are cotton braid over rubber often in colors or a tracer, also strand...Chas — 02:43 PM
trying to identify this wire type
Greetings Phorum members, Hope you can help me identify this type of wire in the photo I have attached.  I am not sure ...georgetownjohn — 01:53 PM
Philco 60 Squealing
All correct shields must be in place, all tubes correct no subs of any kind. Check any soldered, riveted ground conne...Chas — 01:24 PM
Philco 60 Squealing
I have recapped and replaced out of tolerance resistors and so on. Radio plays nicely on fairly strong stations. The pro...dconant — 10:55 AM
Philco 46-420 Code 121 Reception issues
Welcome Eric, I agree with Bob and far as the two main electrolytic filter capacitors did you change them yourself or w...radiorich — 11:43 PM

[-]
Who's Online
There are currently 4632 online users. [Complete List]
» 1 Member(s) | 4631 Guest(s)
Avatar

>