Condenser on Voltage Regulator

[Pat Marshall]

26651

Two Questions:

1) What does this condenser do?

2) What are the specifications?

My 1494 had this, but the wire broke off so I need a new one. Thanks in advance for your response.

[Barry Wolk]

I believe that all of the capacitors on the car are noise-cancelling devices for variable resistors, like gas and oil pressure gauges. If you don't listen to your AM radio I don't think you'd notice their absence.

I built my own stereo equipment in the '70s from kits. They started performing poorly, much like the Mark II radio, and the total fix was modern capacitors. I think their life is time-related, not use related. If I understand properly the capacitors open up when they fail and have no effect.

[Lee Craner]

Pat,

Barry is right, the capacitors reduce radio noise. Their rating isn't important, any capacitor for that purpose will work.

Lee

[Mark Norris]

Anything with electrical contacts that frequently make and break will act as a spark radio emitter hence the voltage regulator, oil pressure sender unit, ignition points and fuel tank level sender each have them fitted to suppress sparks at the internal contacts to a) prevent radio wave emissions that would cause interference, and b) prevent the contacts from burning out or being spark eroded. The capacitor acts as an grounding point for any fast changing voltages (eg. when a contact makes or breaks). Strangely the engine temperature sender doesn't have one despite the fact the original KS units work on the same bimetallic contacts principle.

[Barry Wolk]

Found these in my Elmer Rohn stash. Having them tested.

26713

[Lee Craner]

Barry,

You can test them yourself. Check the lead to the case with an DMM set to low ohms. If it reads infinity, it's good.

Lee

[JohnC]

Are the condensers still necessary if the radio is retro fit with modern AM electronics. I haven't opened my radio but there are a few things rattling around in there.

[Lee Craner]

John,

Noise suppression is more important for AM than FM, and it is still an issue with even modern AM radios.

Lee