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City: Ferdinand
State, Province, Country: Indiana
The problem with the Model 20 speakers isn't so much the cone as it is the spider (the part at the center of the cone with a screw or bolt in the middle, which attaches the spider to the pole piece of the "pot"). The solid spiders used in the Model 20 speakers become extremely stiff with age and make the speaker sound much like one of those 1920s high impedance cone speakers - in other words, no fidelity. I wasn't around in 1930 - I didn't make the scene until thirty years later - but I suspect those spiders were stiff in 1930, also.
I had to recone a speaker for a 20 a few months back; I used the spider from an old 112 speaker with a bad cone. What a difference. This is now the best sounding 20 I've ever owned.
In 1931, Philco switched from solid spiders to spiders that look much like 45 rpm adapters, only smaller and made of fiber, of course. These have much more flexibility and allow the speaker to have greater fidelity.
--
Ron Ramirez
Ferdinand IN
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City: Roslyn Pa
When I was working on my model 21 I had a modern speaker hooked up to it's original output transformer and your right! WHAT A DIFFERENCE!! Didn't know the little Philco had it in him. It will make tiny tim sound like Thurl Ravenscroft! If you don't know who Thurl was he was singer on the Grinch song and was Tony the Tiger "THERE GREAT" from the beginning(1953 or so) till the mid 1980's. Great voice!!!
Terry
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
Posts: 40
Threads: 2
Joined: Jul 2011
Sorry to have been so quiet recently. I did notice that the cone has begun to seperate from the surround on my speaker. I will more than likely have to sub in a modern speaker until I can get this one repaired. Question is how do I wire it in? (remember I'm still relatively new).. Thanks for all the great advice so far!
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City: Roslyn Pa
The short answer is to disconnect the voice coil from your old speaker and wire in the new one where the old one was connected. This will work fine for testing. If you want a more permanent setup you will need a speaker, choke,(to replace the field coil) and a p/p output transformer.
Terry
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
Posts: 40
Threads: 2
Joined: Jul 2011
Running through the voltage check and I came up with 8 volts on the plate of the first 24 tube. 236 volts on the 2nd and 95 on the 3rd. Both 71's come up 233 volts. The 27 has 111 volts. Terminals 1-2 on the condenser block have 276 volts. All voltages from the power transformer check out great. All caps are good. All resistors check out close to spec. She is definitely sick somewhere.. Ideas?
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Joined: Dec 2009
City: Roslyn Pa
Yeah I got an idea. The primary on the second rf coil is OPEN. Simple fix is remove coil from chassis. Replace primary winding with 50t of small gauge magnet wire. 30-40G will work fine.
Terry
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
Posts: 40
Threads: 2
Joined: Jul 2011
Decided to do a second voltage check to be sure I wasnt missing anything. This time as I went through the check I touched the VM probe to pin 2 of the 1st 24 tube and the radio roared to life! The erie part of it was that blasted a radio station that only plays old music. The volume control was turned down and the sound was BLASTING out of that old dameged speaker(which faired pretty well). Crystal clear too. No static. When I took the porbe off the pin the set went silent again. Touch it again and it came back on. Try to tune another station and it goes dead. Incidentally that tube is now reading 80 volts on the plate. Maybe its possessed.
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City: Roslyn Pa
If it is working properly you should be able to hook an antenna the ant post and use the volume control to control the volume. The reason is plays loudly when you hook the meter lead to it is you are bypassing to volume control.
Terry
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
Posts: 163
Threads: 8
Joined: Jun 2011
City: Chicago,illinois
Terry, I was hoping it was possessed.
Posts: 40
Threads: 2
Joined: Jul 2011
But why will it only receive that one station? Its around 1200 on AM. My big Zenith console just barely tunes in that channel but its crystal clear on that Philco. Not even my modern sets will tune it in. When I hook up an antenna it wont work. Only when i touch metal to that pin. The volume control still works too. The station blasts forth with the volume all the way down and still gets louder. Theres probably a simple explanation that my newbie brain cant quite figure out.
Posts: 7,288
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Joined: Dec 2009
City: Roslyn Pa
Hey Jimmy,
The one I'm working on now IS! It's a 84B that the local oscillator refuses to run. Still got a few tricks up my sleeve to get it back on track.
Waxie,
Unplug the set. Turn the volume all the way up. Connect ohm meter to ANT post and GND post. How many ohms you got?
Terry
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
Posts: 40
Threads: 2
Joined: Jul 2011
Set unplugged, volume on full: 24-30 ohms. All the way down is 5.6K ohms.
Posts: 7,288
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Hmmmmm.
I just checked it against my model 21 and that is correct. You may want to check the wires that go from the tuning condenser to the rf coils. You can also check the resistance from the connections at the tuning condenser to ground. If good should show a low resistance like a few ohms.
Terry
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
Posts: 40
Threads: 2
Joined: Jul 2011
The smaller windings (secondary?) in the first RF coil disentegrated in my hands when I pulled it to do inspection. Im guessing this is my problem. I will need to re-wind it as you mentioned here in an earlier post. Does the wire need to be re-wound in the same direction as the original? If so, how was it wound. The majority of the wire on mine literally fell apart as I pulled it from the chassis. Just crumbled in my fingers and now I cant tell which way it was wound. I did note the "in" and "out" though. Any ideas where I can get the wire?
Posts: 7,288
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
The original wire was cloth covered when you replace it you can use enamel coated magnet wire. It can be had at Radio Shack. the size isn't very critical any thing from 32G to 40G will work fine.
http://www.philcorepairbench.com/tips/svctip36.htm
Terry
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
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