|
trendal
J♠



Registered: 04/17/01
Posts: 20,815
Loc: Ontario, Canada
|
Anyone know a thing or two about old AM radio sets?
#27624666 - 01/19/22 02:07 PM (2 years, 8 days ago) |
|
|
I'm working on this Philco 95 that I picked up for basically nothing last year. It's in really good condition, has all the tubes, and is mostly original wiring.
 
Mostly, except for the part I'm stuck on 
Some modifications were done, in the 50's, apparently to fix some caps and especially the winding in the antenna transformer - which was apparently removed entirely.
Also apparently, the fixes that were made to it didn't have a lasting effect - the set blew its main power resistor along with a few caps. Would have liked to see that one!
I am trying to get it back to as much of a "factory" state as I can...but how many turns do I put on the pimary of the antenna transformer? 
--------------------
Once, men turned their thinking over to machines in the hope that this would set them free. But that only permitted other men with machines to enslave them.
|
Jean-Luc Picard
I only wish i was this good!



Registered: 12/30/07
Posts: 4,177
Loc: New Mexico, USA
|
Re: Anyone know a thing or two about old AM radio sets? [Re: trendal] 1
#27624882 - 01/19/22 05:35 PM (2 years, 8 days ago) |
|
|
I couldn't directly answer your question about the number of turns, but I did find a really helpful forum.
Philco Radio Website The forum has a ton of neat info on restorations and operation. The library also has a ton of info.
Philco Set Index It looks like the Model 95 was only produced in 1929. You can use that to find manuals and schematics in the library.
Model 95 Schematic
Hope this helps a little bit, or at least gets you into the right forum where somebody more familiar with philcos can get you your more specific questions answered. 
-------------------- The universe is under no obligation to make sense to you - NDT
|
trendal
J♠



Registered: 04/17/01
Posts: 20,815
Loc: Ontario, Canada
|
Re: Anyone know a thing or two about old AM radio sets? [Re: Jean-Luc Picard]
#27624897 - 01/19/22 05:50 PM (2 years, 8 days ago) |
|
|
I already have an account on the philco phorum
--------------------
Once, men turned their thinking over to machines in the hope that this would set them free. But that only permitted other men with machines to enslave them.
|
Jean-Luc Picard
I only wish i was this good!



Registered: 12/30/07
Posts: 4,177
Loc: New Mexico, USA
|
Re: Anyone know a thing or two about old AM radio sets? [Re: trendal]
#27624900 - 01/19/22 05:55 PM (2 years, 8 days ago) |
|
|
Ah dang, and here I was thinking I was being helpful
-------------------- The universe is under no obligation to make sense to you - NDT
|
nooneman


Registered: 04/24/09
Posts: 14,555
Loc: Utah
|
Re: Anyone know a thing or two about old AM radio sets? [Re: trendal]
#27624901 - 01/19/22 05:55 PM (2 years, 8 days ago) |
|
|
Beautiful! I'm afraid I can't help much other than suggesting counting the turns and replicating it. Still I hope you update this thread with your progress as you work, I'd love to see how this turns out. Some shots of the internals would also be fascinating.
|
trendal
J♠



Registered: 04/17/01
Posts: 20,815
Loc: Ontario, Canada
|
Re: Anyone know a thing or two about old AM radio sets? [Re: nooneman]
#27624922 - 01/19/22 06:18 PM (2 years, 8 days ago) |
|
|
Yeah, it's the number of turns that has me stuck 
Whoever did work on it last seems to have removed the primary windings completely...so I have no idea how many were on there to begin with!

I've traced all the modifications. The transformer likely had an open primary - Philcos of this era are notorious for having RF transformers with open primaries...the insulating strip used in between the primaries is cellulose, which goes bad over time releasing acids to eat the exposed primaries.

I am not sure why the guy just removed it entirely...he seems to have had some knowledge, but no parts
--------------------
Once, men turned their thinking over to machines in the hope that this would set them free. But that only permitted other men with machines to enslave them.
|
|