Crawls Backward (When Alarmed)

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Rebuilding/Restuffing Filter Cap Can on Supro 1616T

I'm going to remove and restuff the filter capacitor 'can.'  I unsoldered all the leads, as you can see here.  It's a good idea to make a drawing of everything so it can go back as it was.

Especially good if you have a pause of a couple of days in the middle of the operation.

There are four wood screws that hold the chassis in from the sides of the cabinet.   I can't tell you how much easier this is now that I have my Ridgid Fuego cordless drill.

I was pleasantly surprised to see that Valco mounted the capacitor can to a fiber mount which then bolts to the chassis.  Super easy to take this off compared to a Fender amp, where the can is soldered on.

With the capacitor removed from the chassis, you can see how the mount works.  The two mounting tabs on the can just pass through slots in the mount.  I just untwist them to remove the can.  What could be easier?

I suspect Fender soldered their cans to the chassis because it's cheaper than this type of mounting.  The mount costs money, as do the screws and nuts.  Leo Fender was known to have watched costs meticulously - this mounting would have cost too much money for him!

I used a big kitchen knife to cut the can apart at the bottom where there's a seam.  Roll the can back and forth and the knife will make a nice thin cut through the can.

Slide the top of the can off and you can get to the innards.

I then just cut the actual capacitor off at the base.  Use gloves to handle the capacitor.  The paper and foil 'roll' has some sort of paste on it; I bet it's not good to handle it.

Mount your new modern caps on the base.  This particular cap uses one 20 uF and two 10 uF sections.  I put three discrete Panasonic caps in as a replacement.

Tie the grounds together and run the positive leads through the base to their respective tabs.


Slide the cover back on, and epoxy the base and cover back together.  I've been using JB Weld epoxy.  Then I gently clamp it together in a vise until the epoxy sets.

The end result looks like the original.

You may have noticed this is the famous Mallory FP cap.  Very common on mid 1950s through 1960s American electronics.



 
 
 
 

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