"Woody" wrote in message
...

"RJH" wrote in message
...
Hi - can anyone identify this bulb:

http://tinyurl.com/3cf2h

from a Pioneer SX 750 receiver, late 70s model? It's about 3mm in
diameter
and is used on the panel to indicate 'stereo'. And where to find a
replacement?

Many thanks

Rob



Check the polarity and voltage of the supply and replace it with a LED.
The
negative side of the supply goes to the LED leg that has a small flat on
the
LED body next to it.

You should have no difficulty in finding a suitably sized LED, but it will
need a current-limiting resistor in series. Take the supply voltage,
deduct
2 and divide by 10. This will give the value of resistor in K-ohms needed.
E.g. suppose the supply is 12V, 12-2=10/10=1K. That will runs 10mA through
the LED which will be more than enough. If it is too bright try increasing
the resistor value by factors of 2 each time. The resistor will need to
have
a power rating of 0.25W or higher. The resistor can go in either leg.


--

Woody



Many thanks for that Woody - I will give it a go. But, I can't figure out
what the voltage is!

I attached a voltmeter to the 2 wires coming out of one the lamps that work
('Power') and couldn't get it to measure much - it was switched on, the
voltmeter read a battery correctly, but no DC current on the bulb supply
except an occasional 0.3v - not steady though.

I clearly have no idea what I'm doing here so any further guidance
appreciated!

Rob