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Speaker Replacement
#1

Hello everyone, this is my first post, but I’ve been reading and learning here for a while.  

I have decided to restore my 38-93 that belonged to my Grandparents, I imagine they bought it new.   I’ve had it for a non-working mantle piece for 25 years.
 I’ve been dabbling with electronics for a while, building stomp boxes and simple guitar amps for friends, but that is about the extent of my experience. This is my first tube radio and I’m completely addicted to working on it.  
I’ve spent hours mapping the chassis on paper, taking pictures identifying parts and making notes.
 Last night I got down to testing the resistance of the field coil and output transformer. According to the drawing (37-93) the field coil has an R of 1140Ohms and the output transformer has an R of 400Ohms.  I got no reading on either. Is this thing toast? Can they be re-wound? I would like to use this speaker since it’s the original if at all possible.
This is such a great site, I’ve already learned a ton of stuff I would have had a hard time learning otherwise.  Thanks in advance.


Attached Files
.pdf Model 37-93.pdf Size: 108.95 KB  Downloads: 156

"He has all the virtues I dislike and none of the vices I admire." — Winston Churchill
#2

Hiya Green and welcome!
Your spkr is toast sorry! Can replace it with a similar type, try an ad in the wanted section.
Or
Use a modern spkr replacing the FC with a choke or resistor. Then use a suitable matching transformer @ 7k to 8 ohms. I can go into more detail if you like.

GL
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
#3

(08-17-2016, 04:15 PM)Radioroslyn Wrote:  Hiya Green and welcome!
Your spkr is toast sorry! Can replace it with a similar type, try an ad in the wanted section.
Or
Use a modern spkr replacing the FC with a choke or resistor. Then use a suitable matching transformer @ 7k to 8 ohms. I can go into more detail if you like.

GL
Terry

Thanks for the reply. I would love for you to go into more detail.

"He has all the virtues I dislike and none of the vices I admire." — Winston Churchill
#4

(08-17-2016, 07:35 PM)Greenhorn Wrote:  
(08-17-2016, 04:15 PM)Radioroslyn Wrote:  Hiya Green and welcome!
Your spkr is toast sorry! Can replace it with a similar type, try an ad in the wanted section.
Or
Use a modern spkr replacing the FC with a choke or resistor. Then use a suitable matching transformer @ 7k to 8 ohms. I can go into more detail if you like.

GL
Terry

Thanks for the reply. I would love for you to go into more detail.

Check PM box
tnx

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
#5

Welcome to the Phorum!
Icon_wave
#6

Thank you. Icon_smile

"He has all the virtues I dislike and none of the vices I admire." — Winston Churchill
#7

Hello Everyone,

I found a possible replacement for the speaker for my 38-93, it’s from a 37-84.
The Output Transformers (32-7019) match, the Field Coils (36-3243) match, but the Voice Coils do not…..36-3014 for the 38-93 and 36-3157 for the 37-84. Can I use this speaker?
Any education is greatly appreciated.

"He has all the virtues I dislike and none of the vices I admire." — Winston Churchill
#8

Should work fine. Both set use the same output tube so it is a good match. The transformer matches the tube's plate impedance to the impedance of the VC. VC probably just has a different part number but the proper impedance.

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
#9

I merged the thread with the original speaker thread to keep it all together.
#10

Thanks Terry, Thanks Bob.

"He has all the virtues I dislike and none of the vices I admire." — Winston Churchill




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