Crawls Backward (When Alarmed)

IconProjects, musings about guitar builds, guitar repairs, vintage tube amplifiers, old radios, travel, home renovation, and other stuff.

Hacker RP38A Restoration Continued

Before I can build any new pedals, I need to finish the Hacker mini-restoration.  The caps I ordered from Mouser came in and I want to finish it up and get it off the bench so I can use it again!

I have a copy of the Hacker factory RP-38 service manual, but unfortunately, there are quite a few changes that were made to the -38A model.  However, I can gather enough general instruction to suss out how to get the chassis out of the cabinet. 

There are aluminum caps over the screws that hold the handle and the chassis in place.  The caps come off easily with a small screwdriver. 

With the caps removed, the screws that hold the handle and pass through the cabinet to hold the chassis can be removed.  

The order of the spacers and washers is important.  If they are reversed, the handle won't swivel.

Just to make sure I'd get the order right when I put it back together, I took another shot of the screws after I removed them.  And yes, I did wind up referring to the picture later! 

Next, slide off the external aerial (antenna to Amerikans) connectors. 

The green arrow in this shot shows the plug for the 18v external power that needs to be removed.  It simply slides off.

Now the whole chassis can be removed from the cabinet.  Very straightforward.

Here's the backside (hee hee) of the RF circuit board.  This is what I need to access to change out the electrolytic capactitors.  If you look carefully (see the larger version), you'll see a resistor and capacitor or two added here - I believe these were changes made by the factory during production.

I want to spray some contact cleaner into the volume, treble and bass pots.  To access them, I need to remove the dial scale. 

There are three small screws and lockwashers on each side of the dial scale fixing/trim that have to be removed.

Pull off the knobs, remove the screws, and the dial scale comes off.

I thought the scale might be glass, like my 1950s German, Swedish and Polish radios, but it's plastic.  Lighter and safer, especially since it's made of unobtanium.

The trim is plated metal - I used metal polish to clean it up.


Post a Comment 0 comments:

Post a Comment