I've been working on an RCA RZS488D radio alarm clock lately. I just
had to replace the rotor w/ one I found on fleabay. This rotor did not
have the winding for the dial light, so I am investigating other ways
of powering it. In the process of seeing what power was available from
the power supply, I found a 220K, maybe 2W resistor in parallel with
the rectifying diode. The original rectifying diode was only marked w/
6EA. Since the schematic I had showed no such resistor I removed it
and at the same time installed a 1N4007 diode. The radio is currently
playing behind me. What might have that parallel resistor have been
for? I have never seen that type of setup as of yet.
On the subject of the dial light, the original was a #1490, 3.2V,
0.16A bulb. Without the extra winding in the clock motor, what would
be the best way to power this? There is a 36V DC source off the power
supply that I could step down. I would prefer that the light not be
very bright. Any ideas?