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Philco 90 Restoration
#31

Jake Blake Wrote:...so is there a way I can determine if the 610 originally came with Sprague, Mershon, Solar capacitors,. . . or cans branded Philco ?

Model 610 originally used aluminum electrolytic cans, branded Philco.

--
Ron Ramirez
Ferdinand IN
#32

Hey Steve, question for you:

Is that a copper ring you are using as a negative electrode, or a piece of wire bent into a circle?

--
Ron Ramirez
Ferdinand IN
#33

"Model 610 originally used aluminum electrolytic cans, branded Philco."

Thank you Ron!  I guess my search for those cans continues.  :-)
#34

Ron, yes, it is a piece of wire. The original plan was to leave the wire coiled under the can to make contact with the metal disc on the fiber insulator but, I worried it wouldn't make a solid connection so, I brought it out and tucked it down through the metal grommet in the insulator and made a solder connection. Look closely at the photo in post #29.

Steve

M R Radios   C M Tubes
#35

Another problem. I began the alignment. The IFs were almost right on, only the slightest improvement was made on one adjustment. The front end was a different story. I had the trimmers backed way out and still not peaked. That turned out to be a mechanical problem, I had not indexed the dial properly. That was easily fixed. But still, I couldn't get the thing to track. After looking for a while and some head scratching, it hit me. The trimmers on the tuning condenser have two different size adjustable plates, the one for the oscillator section is smaller than the other two. When I assembled the tuning condenser, I had it in my head, the front section was the oscillator, while actually the most rear one is the oscillator. The bad thing about this is, you can't get to the screws so, I had to remove the condenser to correct this problem. After everything was back together as it should be, the radio aligned perfectly. Even after "rocking" the bottom end, the dial is almost right on.

[Image: https://live.staticflickr.com/65535/4923...d01c_k.jpg]100_0195 by Steve Davis, on Flickr

The radio has been playing for several hours now. The only problem I see is the dial light flickers and sometimes goes out and the volume control is a little scratchy. I still have to paint the tube shields and I have that speaker problem to deal with.

Steve

M R Radios   C M Tubes
#36

The volume control works well after a little cleaning and lube. The dial light was also an easy fix, I cleaned and polished the screw base with a Scotch Bright pad and added a fresh drop of solder to the center contact. I painted the large tube shield and the flat one.  Anyone know a good place to get new model and tube location stickers?

[Image: https://live.staticflickr.com/65535/4924...6e39_k.jpg]100_0220 by Steve Davis, on Flickr
[Image: https://live.staticflickr.com/65535/4924...345e_k.jpg]100_0221 by Steve Davis, on Flickr

M R Radios   C M Tubes
#37

Now the speaker. The correct speaker for the late version 90 is nearly impossible to find. The push-pull 47 pentodes need a much higher impedance speaker than the 45 triodes used in the early version 90. I had planned to make do with an early version speaker but as it turned out, the one I had, has a bad output transformer. The cone is bad also and I had planned to replace it. So, up to now, I have been using the speaker out of my Philco 20 for testing the chassis. 

[Image: https://live.staticflickr.com/65535/4924...5f12_k.jpg]100_0200 by Steve Davis, on Flickr

I removed the transformer, the cone and the field assembly. I then cleaned and painted the "pie pan".
[Image: https://live.staticflickr.com/65535/4924...69a6_k.jpg]100_0202 by Steve Davis, on Flickr

Steve

M R Radios   C M Tubes
#38

Check with Nathan Slingerland. He has produced a lot of different labels.
#39

I have a NOS Philco output transformer p/n 32-7078 as used on the K-17 and H-13 speakers. Using a variac, I determined the turns ratio to be about 65:1 that gives an impedance ratio of about 4525:1. Pretty low considering the .62 ohm impedance of the K-5 voice coil. I just happened to have an 8 ohm coil the right diameter but, the thing is to long. Also 8 ohms is a little too much. 
 [Image: https://live.staticflickr.com/65535/4924...6a02_k.jpg]100_0204 by Steve Davis, on Flickr

So, I removed about one half the turns and shortened the coil form.
[Image: https://live.staticflickr.com/65535/4924...a38d_k.jpg]100_0206 by Steve Davis, on Flickr

Steve

M R Radios   C M Tubes
#40

[Image: https://live.staticflickr.com/65535/4924...a3fd_k.jpg]100_0223 by Steve Davis, on Flickr

M R Radios   C M Tubes
#41

I installed the cone using a new accordion style spider and installed the new output transformer.

[Image: https://live.staticflickr.com/65535/4924...4df0_k.jpg]100_0214 by Steve Davis, on Flickr
[Image: https://live.staticflickr.com/65535/4924...f3f5_k.jpg]100_0219 by Steve Davis, on Flickr
[Image: https://live.staticflickr.com/65535/4924...ab9e_k.jpg]100_0216 by Steve Davis, on Flickr
[Image: https://live.staticflickr.com/65535/4924...8544_k.jpg]100_0212 by Steve Davis, on Flickr

M R Radios   C M Tubes
#42

It will sound better but you are going to have to space the speaker back so that the foam-roll does not rub - otherwise it won't sound better.

"I just might turn into smoke, but I feel fine"
http://www.russoldradios.com/
#43

Oh yeah, I learned that lesson when I first started using these cones. It does sound good, it will sound even better when I get it in the cabinet.

Steve

M R Radios   C M Tubes
#44

My new cabinet has been waiting for the chassis
[Image: https://live.staticflickr.com/65535/4903...375e_z.jpg]Philco 90 Reproduction Cabinet by Steve Davis, on Flickr

Everything has been installed in the cabinet
[Image: https://live.staticflickr.com/65535/4926...611a_k.jpg]100_0239 by Steve Davis, on Flickr

Merry Christmas to me!
[Image: https://live.staticflickr.com/65535/4926...0d69_k.jpg]100_0247 by Steve Davis, on Flickr

Steve

M R Radios   C M Tubes
#45

Philco would be proud.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.




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