[morzh]

I am eventually back in my workshop, after 10 months of suffering through the repair and the consequences of it.

This radio was acquired by me for a very reasonable price of upward of $40 a year ago, during the Kutztown show of 9/2023.
I am trying to assemble a collection of 38-12, towards which I already have a brown backelite one.
I could also count the 38-15 in a wood cabinet I have towards it, as these two radios are exactly the same, with a SW antenna coil and the switch  for it added.
So I bought this wood cabinet one, and a wood white-painted (the factory painted) one.
I would love to have the Plaskon one too, but they are exceedingly rare. Ron bought one and it came broken, so he had to glue the case together and then refinish it.

Anywho, the shape of both the case and the chassis of this one are excellent, and I don't think I will be doing anything to the cabinet.
The chassis is very clean, and, though I do not like it, it was restored at some point. Not to my standards, but it is, all in all, a good restoration. It's just I am not a fan of hanging caps and electrolytics over the existing old parts. Even if it is properly done (they are).

After having realized the radio has been restored, I simply plugged it in, and it worked OK. It pulled in our local station, fairly clear. It has some "motorboat-like" hum, which only exists when the station is not on. It is not motorboating, per se.

Then I tested the tubes. All, except the rectifier (84) are in good to excellent shape. The rectifier was not just weak. It was VERY-VERY weak. And it still worked. Luckily, I bought a few junkers a couple of years ago, one of which was 38-12, and the tube in it was super-good, tested like new. This said, it made very little difference in reception.

As seen from the photos, not all caps have been replaced. I intend first to replace all of the original caps, then tackle the electrolytics and those that are outside of the backelite etc.

This is the first photos, the case and the chassis.

   
   
   
   
   
   
   
   
   
   
   
   
   

[morzh]

Today I :

- stuffed the old tubular caps
- stuffed the backelite block (two Y-caps), and
- replaced the disk ceramic caps and the sole axial film one with the old caps' shells with axial caps inside.
- Plus Iremoved the 30uF 50V cap that was there between the GND and the Negative. It is not in the schematic, so even if it is good, I do not want it. Plus it seems it did not affect anything in a negative way.
The radio works a bit better. I also realized the strong noise (which I never heard before) is coming from my workbench's light fixture, which has a switcher inside.

I also need to restuff electrolitic caps plus fix the values (the 1st cap is 20uF instead of 12uF).

[morzh]

Today I replaced or parallelled (if the deviation was not too large) the resistors.
One particular resistor puzzled me for a while.
It showed 7.3M and it should've been 190K. I 've seen my share of open resistors...but the radio worked fine.
I have another chassis I keep on the bench for reference; it was acquired independently about 2 years ago for $5. In good shape.
So, I looked at the same resistor there, and it showed....10M. I started doubting myself. I even thought it was some variation. I tried to look for 190K resistor but to no avail. Then I measured the voltage on the plate of the IF, where that resistor was the load, and saw 20V instead of 90V.
So I replaced it, and the voltage came back normal. The radio worked the same way as before.
I never saw two resistors in two chassis failed the same way. Bad batch?


Spare chassis' resistor
   
Its resistance
   

My chassis' resistor
   
Its resistance
   


Now just replace the electrolytic caps.

[morzh]

Attempted to extract the electrolytic caps; the corner one would not come out. The previous guy put some hermetic over, and none of my pliers or adjustable wrenches fit.
I ordered some deep sockets I do not have: 7/8/ 13/16 and 1" - good reason to order, and I am sure, one of them will do the job. They promise Thursday delivery. I will proceed then.

[morzh]

7/8" socket came yesterday, and then it was a walk in the park to extract that 4uF cap.

Both caps exhibit 70% rise in value, and when shaken, a liquid splashing is heard inside. I take it, they are beyond the repair (reforming) and tonight both will be drained and opened in order to be re-stuffed.