Recapping a vintage radio is the first step to getting it working like new.

What if the radio already works? Should it still be recapped?
If it still has the original electrolytic and paper capacitors, it needs to be recapped.

Can I reform capacitors?
There are some that claim they can reform capacitors. Unfortunately, this is not a good practice. Modern components are more precise and will last longer. Also, the process involves removing the old capacitors. Might as well replace with new parts. Some like the look of the old capacitors and will remove the innards and replace them with modern components.

First step
READ THE SAFETY INFORMATION! I CAN NOT BE HELD LIABLE FOR ANY INJURIES YOU RECIEVE. YOU SHOULD KNOW AND UNDERSTAND THE RISKS.
Second step
UNPLUG THE RADIO! DISCHARGE THE CAPACITORS in case of stored charge.
Third Step
Get the radio schematic. Many of these can be found in the Rider repair manuals. Just look in the index first.
Verify you have the correct capacitors that need to be replaced.

Paper and wax capacitors can be replaced with orange drop or yellow drop capacitors. These capacitors are made from polypropylene or polyester film. Just make sure the capacitors can handle the voltage. If you need capacitors, you can get them from here: https://www.justradios.com/capkits.html. The yellow axial capacitors work very well.

Fourth Step
Take good pictures of the radio. You want to know where all the components connect. I once recapped a radio that refused to work. After reviewing the photos, I realized that I had connected a cap to the wrong tube pin, and the radio WOULD NOT WORK! After connecting it to the correct pin, the radio started playing. All because I took a few detailed photos of the radio BEFORE I started working on it.

Fifth Step
Begin recapping the radio by unsoldering a capacitor lug and removing the old capacitor. Carefully replace the capacitor. The electrolytic capacitors MUST be connected with the right polarity.

There is a debate about the orientation of paper/wax capacitors and modern capacitors. Personally, I have not noticed an issue, but that is my opinion. Just know this is a large ongoing debate in the online community.

Sixth Step: After the new capacitors have been installed, verify the new connections with the photos you took. Make sure the connections are correct.

Seventh Step: Replace the power cord. Old power cords are typically frayed and may short.

Eighth Step: Use your multimeter and make sure the power prongs show resistance between them. Make sure ti is not a dead short.

After you have replaced the caps, congrats! You are getting close to hearing that radio work again!

Go to the next section: Powering Up The Radio – First Time

Want a video demonstration? Check out this video from Mr. Carlson’s lab: