<VV> 1962 radio

[Tony Underwood]

At 07:00 AM 9/29/2007, Frank DuVal wrote:
>Tony may chime in with more details (or to correct mine..), but here goes:
>
>Capacitor, condenser for most automotive people or old time radio 
>people, on the Generator is to remove generator hash noise from the radio.
>
>Capacitor on voltage regulator is to remove the noise produced from 
>the arcing points inside the regulator.
>
>Capacitor on the coil is to remove the noise from the arc of the 
>ignition points.
>
>All three are (were) present on my 64 Spyder with a transistor radio.
>
>The generator condenser even has a nice red paper tag to place over 
>the terminal. They are available from our vendors.
>
>The copper ground straps are to prevent the engine sheet metal from 
>becoming a transmitting antenna for the RF generated from the 
>ignition system. These are also present on most cars, early and late.
>
>So in general, the function of all the above is to prevent noise in the radio.



And NONE of the above will eliminate spark plug noise.    Spark plug 
racket is transmitted, not conducted.   The car parked next to you at 
the light will hear your spark noise on their AM radio as well.   The 
only way to eliminate spark plug noise is to work on the car's 
ignition system; replace bad/flaky wires etc or reduce the coil 
voltage or use resistor type plugs which exist solely to reduce 
ignition noise in the radio.    Of course, this will also diminish 
the effectiveness of the ignition system, but you have to weigh the 
differences.   The factory ignition system, if working the way it's 
supposed to work, will product next to nothing in the radio.

Now:   In some obscure instances, putting a bypass capacitor on the 
car's A+ line to the radio may help reduce ignition noise... NOT 
because it's "conducted" from the spark plug wires or cap etc but 
because it can also radiate onto adjacent wiring in the engine bay 
and walk right along into the radio.

If you have ignition noise on a factory AM radio, you should check 
the antenna to see if the ground braid/shield on the cable is still 
OK.   The factory radios have some pretty serious noise reduction 
capabilities built-in already, so if you manage to get spark noise in 
the factory radio you're trying really hard.


My '60 4-door has non-resistor plugs and resistor wires and there's 
NO spark noise in its original tube type radio.    It had solid-core 
wires at one time and even then spark noise in the radio was minimal, 
on channel it was silent but tune the radio off-station and there it 
was, could hear every single plug each time it fired, buzzzzz right 
in time with the gas pedal.  The resistor wires help eliminate most 
of this off-station plug noise to the point that it's seldom 
noticeable unless I'm hill climbing and the engine is loaded and the 
ignition is working a bit harder to jump that gap.   Not much of an 
increase, but it's detectable with the radio off-channel while 
hillclimbing.   Still, not objectionable except while trying to 
listen to those remote stations at night when skip is rolling in and 
out and they fade away between "phases"... then the spark noise 
creeps back in.   Local stations, never an issue.

And this is with the antique tube type radio.   These tube type 
examples were used in Corvairs through '62.


Now:   Aftermarket radios sometimes don't include as much 
noise-reduction prevention.    They're pot luck.   Gen/Alt whine and 
various clicks and pops can find their way into some aftermarket 
radios, depending on example.



tony..