Packard Forum Index » V-8 (1955-56)

Quote:

It's more involved than just a capacitor. For a transformer to work, there has to be an alternating current supplied to it's primary coil. The vibrator is an electromagnet with a pair of contacts which rapidly turn the the cars DC voltage on and off. In conjunction with a special primary winding on the power transformer, this simulates AC in the primary coil and the transformer will work like others do with voltage(s) out generated by the secondary coil. The magnet and contacts are placed inside the can and surrounded by foam rubber to cut down on the electromagnet's buzzing noise.

Once the radio is on and vibrator has power, there will be a contact which opens and closes voltage to the vibrator electromagnet. The magnet attracts a bar mounted on a piece of spring steel which carries another pair of contacts. Once vibrating, those paired contacts open and close providing a means of reversing voltage to the transformer primary -- almost like an AC current would.

Typically, like any contacts the vibrator contacts can burn and arc. You may be able to remove the unit from the can and GENTLY dress the contacts but the assembly is very delicate with critical spacing and tension so it is also just as easy to totally mess it up.

Electronic vibrators do the same thing but instead of an electromagnet and contacts, there is a solid state oscillator circuit which turn a pair of high current power transistors alternately on and off to excite the transformer primary coil.

thanks howard,

i thought there was something to do with ac, as it is called vibrator,, i thought it was about radio waves, cycles.

better to buy the electronic one...

if i knew mine was bad, i would take it apart.

looking at the picture, i see the paper capacitors, which people replace with the can, or axle type metal ones