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HW-16 Can Capacitor Installation

 

HW-16 Can Capacitor Installation

Filed in Vintage Radio on Jan.04, 2015

The next step was to install the rebuilt and new can capacitors into the HW-16.

As I knew I was getting close to powering the radio up, I decided this would be a good time to replace the old 2-wire power cord with a safer modern 3-wire cord.

The old cord was in pretty bad condition…

 
Old Power Cord

I dug around my junk box and found a retainer for a 3-wire cord. I had to drill out the original hole just a bit to get it to fit. If you go too big here, you are in trouble, as it is a press fit. You have to squeeze the retainer and push it through the hole. Then when you release, the retainer expands to hold itself in place. So go slow on the drilling, trying to fit the new cord between each step up in drill size..

 
New cord with retainer installed

The original design just had the two wires going to the primary of the transformer, without noting which side was hot, and which was neutral. I decided to run the “Hot” wire through the circuit breaker, and the neutral side through the switch. With the surplus power cord I happened to use, the blue wire was neutral, and the brown wire was hot. That might be different in your case, so be careful. The green wire in my case was ground. I added a solder lug to the bolt on the speaker connector and soldered the new ground wire to that.

 
Neutral wire going to the on/off switch.

Now that the power cord was safe, I went ahead with the can capacitor installations. For the two rebuilt cans (with the cardboard on them), I mounted them to their original fiber wafers and mounted the wafers to the chassis. The cardboard was pulling away on one of them, so I added some glue and secured it in place with rubber bands while it dried. For the metal multi-section can from HayseedHamfest, I simply mounted it to the original metal mounting plate using the twist locks, and mounted the plate to the chassis with the original screws. I soldered one of the twist-locks to the mounting plate for grounding.

 
Can Capacitors Installed

When I bought the replacement cap kit from Hayseed Hamfest, I included an order for the power resistor kit. This made it one-stop shopping for the power supply replacement components. They include 3 watt flameproof resistors to replace the 2-watt original carbon composition resistors, along with slightly oversized components to replace the other power resistors. Again, today’s parts are typically smaller for the same ratings, so you can upgrade when you make replacements in many cases.

 
Replacement power resistors

Next step is to replace the electrolytic capacitors in the bias supply…

 

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