[Ron Ramirez]

Thanks Ed. A lot of work, yes indeed!

Tonight I did a bit of troubleshooting.

First, I tried injecting a signal in the SW range. Result: Nothing.

It appeared that the oscillator was not running on bands B, C, or D.

So I did not remove the Magic Brain, but I did remove the top and bottom shields so I could merely flip the entire chassis over and have access to the bottom of the Magic Brain unit. I wanted to specifically examine the area around the oscillator tube and its associated coils, capacitors, and wiring.

Take a good look at the photo below. There will be a test later.

   

Now carefully examine the partial under-chassis wiring diagram of the oscillator portion of the Magic Brain. Again, take a good look, keeping in mind that this diagram is upside down in relation to the photo above.

   

Do you see the mistake I made?

Give up? Well...I accidentally switched the red and green wires at the band switch.

 

After unsoldering, switching and resoldering, it looked like this:

   

Now it matches the RCA diagram.

Did the wire swap fix the "No SW" issue?

You be the judge...

[Video: https://youtu.be/Me9Yj2YS_70]



You will notice in this video that I'm still having difficulty switching from band B to band C.

I think that tomorrow morning, I will remove the Magic Brain top and bottom shields again, hit the band switch contacts with DeoxIT as carefully as I can, and then leave it alone until tomorrow evening or Christmas Day, at which time I will attempt an alignment.