Topic: 46-48 Coil Radio anti-static


kenburke    -- 07-16-2010 @ 12:55 PM
  I was seeking anyone who might know where these items
can be acquired from or an adequate replacement. The radio owner's manual show them as 63-1273 suppressor & 22-1326 condenser. Thanks


supereal    -- 07-17-2010 @ 9:44 AM
  Radio static suppression was tried by putting a condenser between the armature post on the generator and ground, or at the ARM terminal to ground on the regulator, to lessen a whining noise. We also used to put a single knot in the high tension lead from the coil to the distributor. The base of the antenna needs to be well grounded. Often you can diminish interference by tuning the "trimmer" on the radio. You may find it under the tuning knob, or by the antenna input. Turn the trimmer one way or the other until the static is lessened. Stopping static on the AM band is a losing proposition, in most cases. My '47 has a "wonderbar" original radio converted to AM-FM. The FM side does away with the spark noise, but the AM is noisy on all but local stations in spite of our best efforts to kill it.


TomO    -- 07-17-2010 @ 9:50 AM
  The shield on the antenna lead has to be well grounded as well. Weak stations will have more static than stronger ones. If the paper capacitors in your radio are weak or someone substituted capacitors that were outside of the tolerances, it will be difficult to reduce the static to a level that will make listening a pleasure.

Tom


kenburke    -- 07-17-2010 @ 12:39 PM
  Thanks, I have condensers on the car. One by the regulator. So a couple of thoughts, I am running 6v. Converting to a 6V alternator, will that help? Converting the radio to am/fm sounds good. Question, will a condenser for a 12V system work on 6V? I was thinking it does not care. Grounding the antenna at the shield is at the radio? Correct? I would still like to install something at,or in the coil wire? Currently I did not see anyone in the Times on radios. So someone/somewhere must have something that will work.


TomO    -- 07-18-2010 @ 9:02 AM
  Kenburke,

The antenna lead shield should be grounded at both ends. The antenna and the center lead in should not be grounded.

Use your ohm meter to check the parts that should not be grounded.

The generator or alternator noise is sounds somewhat like a siren, the ignition noise is a popping sound similar to the sound that is made when you hold a spark plug wire close to ground.

An alternator would probably not fix your problem. They seem to create more of a whine than a generator.

I would clean the underside of the fender where the antenna mounts and make sure that the correct washers are used, I prefer an internal tooth star washer against the inner side of the fender, and that the nut securing the antenna is tight.

Next I would clean the mounting point for the radio case to ensure a good ground there. Make sure that the antenna plug is cleaned of all corrosion before it is plugged into the radio.

I would also use a star washer at the grounding point of the condenser mounted on the regulator. Your condenser may also be open.

A quick check is to connect an ohm meter on the highest scale across the condenser. The needle should move toward 0 ohms and then back to infinity. To repeat the test, reverse the polarity of the test leads.

Tom

This message was edited by TomO on 7-18-10 @ 9:15 AM


supereal    -- 07-18-2010 @ 9:42 AM
  Ken: Condensers are not voltage sensitive. You can experiment to see if they help by using a spare ignition condenser placed across various places in the radio circuit. A condenser allows direct current to flow while shunting static to to ground. Much of the interference that plagues AM reception enters the radio thru the power lead, rather than the antenna. General Motors encountered this problem when they introduced the Corvette, and devised a metal shield to surround the distributor and coil, preventing the car wiring from becoming a sort of antenna that polluted the radio reception. On some highly affected vehicles, we were able to lessen the static by inserting a brass strip around the rear hood gasket on the firewall, which provided a ground to the hood itself, forming a shield. Eliminating ignition static altogether is unlikely, at best.


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