The PHILCO Phorum

Full Version: Model 16, Code 125
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I'm working on a Model 16, code 125. I've got the smaller 4-section filter cap replaced, the black bakelite tubs restuffed, and I'm working on the main filter caps, a dual 91 and 98.
Someone else worked on this and some things were switched around, and replaced.
The Dual 91 can was original. It has 2 connections on the bottom, and was isolated from the chassis with a cardboard ring. The single cap (I'm assuming 98) had been replaced. The black lead was connected to a tab, which was shoved up between the cardboard and the can of 91.
Is this correct?
I'm replacing the dual and single, and putting all 3 in 1 can to simplify things.
The Question is: Do I have the polarity marked correctly? (Highlighted in pink).
According to the schematic, It doesn't look like the 91 can should be isolated from the chassis. Or is my brain fried?  Icon_crazy
Any help appreciated.
[Image: 49710869841_f399d2e3d5_k.jpg]
I'm thinking that, according to how it was hooked up before, that 2 neg leads would connect to the tab, and the pos of the 3rd would also connect to the tab, which would be shoved up and ground to the can, and still isolated from the chassis due to the cardboard ring.
Is this right?
All three negatives connect to the can, which is connected to the center tap of the high voltage winding. The positive ends connect one to each end of the choke and one to the chassis ground.

Steve
I got the Filter caps resolved, and the radio is up and running.  Icon_thumbup
Now I'm troubleshooting a couple things. A dirty volume control, and a faulty tuning mechanism.
Someone has had their hands on it before me.
Can anyone tell me on this Code 125 how the dial mechanism is supposed to work? The current routing of the cord is not working, and, frankly, doesn't look correct.
I'm wondering, after examining it, if it's supposed to have a tension dial cord on the "back" mechanism, and a dial belt on the "front" part of the mechanism.
If anyone has any pictures, diagrams, whatever that they could post or link me to, I'd be most grateful.
Here's 2 pics before I took it apart.

[Image: 49725649657_2db391d13e_k.jpg]

[Image: 49725650302_d39d776484_k.jpg]
#91 has to be isolated from chassis if used as astandalo e can, as uts + is to the chassis,and the - which is the can is not and so shouldn't touch it.
Hi Jeff - here are a few photos I found of my Code 125 chassis dial string. I hope they help!

[attachment=21904]

[attachment=21905]
Thanks Nathan. How many turns are on the lower left shaft? (Shaft behind the tuning knob) I had a smaller cord than what was on there, and there didn’t seem to be enough ’drag’ to get it to work.
Ah! Check out this previous thread:
https://philcoradio.com/phorum/showthread.php?tid=16020

If it's slipping maybe try rosin on the cord or larger cord?
https://philcoradio.com/phorum/showthrea...r&tid=2783
I got the tuning mechanism sorted out. It still slipped, so I brushed some liquid Plasti Dip in the groove of the shaft behind the tuning knob. That did the trick of giving the cord some grip.
I also cleaned the volume control.
Next is to align it. Although it seems to be pretty good at this point.
Here’s a short video of sampling the AM dial. The Big Band Music is from my AM transmitter.

Sounds swell! Fine work. Paul.
Continuing on the restoration.
The volume pot was iffy. I took it apart, and discovered cracks in the wiper surface. So I ordered and just replaced the control.
I did an alignment, but I’m getting this weird oscillating between 14-16 MHz on the upper SW band.
Is there something I should look for, like an out of tolerance resistor or mica cap that might need replacing?
Here’s a video demonstrating it.



[attachment=22306]
For the dial stringing I might suggest clicking on the portal tab at the top left of the page and then on the lower right click on the Philco Library. Then if you look at the dial stringing information for model 14, 17 etc ( a whole bunch of part #s)I think you will find what you need. Although it is not mentioned or I missed it.The dial stringing for the model 16 code 125 is I think the same as the model 17. If memory serves me correctly the original dial string was 0.060" or 0.065" and something up to .090" has been discussed. If your dial string is not thick enough you will have slipping no matter how tight you make it or how strong the spring is. I found this out on a model 17 which is pretty much a model 16 with less shortwave coverage.
GL,
Henry
Any ideas or tips on the odd signal on the SW band?
Posted on your FB a few days ago some other things. Do you have a shield on the 76 tube?
Yes.
I tried swapping the 76 tube as well with a known good one. Same result.
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