Ceriatone Forum

I need a new pilot light for my OTS.  I'm having a tough time finding 5/16" 6.3v AC replacement.
Does anyone know of a USA source?  I see a few people have drilled out their chassis and installed a Fender light.  I do prefer the authentic small one.  Has anyone converted to LED?  I guess I would need a series resistor and a diode.

thanks!

Here ya go:

http://ceriatoneforum.com/index.php?topic=4037.0

Great! - thanks for the link.

The Mouser item looks exactly the same but its a 6v LED (comes with a series resistor), I think Nick is using a neon lamp to work with the AC supply.
I wonder if I'll still need a parallel diode to keep the LED from flickering and protect it from the reverse voltage.
I guess I'll have to experiment.

thanks again for the info!

Would you please let the rest of us know what you find out and if the Mouser LED can be used? The old thread really never answered that question and my pilot light needs to be replaced too. Thanks in advance

Sure, I ordered a few from eBay.  They look exactly the same but are listed as 12 volt DC.  I'm assuming they have a series dropping resistor to get the proper operating current through the LED from a 12 volt source.  I guess I will have to lower the value to maintain the current with a 6.3 volt source.  Then add a diode to shunt the reverse voltage from the AC.

I'll post my findings but it might take a while, the seller was in China and he put them on the "free shipping" slow boat!

I received the replacement LED from eBay and finally got around to making the switch.  Here's my report.
The LED version looks exactly the same on the front panel. it doesn't have a colored lens, just a colored LED. The shaft inside the chassis is longer but not so long that it hits anything.  Pulling the assembly apart reveals a 1.2k resistor in series with the LED lamp on my 12 volt DC version.  The eBay seller offered 24 volt versions which differ I imagine in the size of the series resistor only.  Typically a 5mm LED likes about 2-4V dc and about 20ma.  These values vary depending on color and output of LED.  The two issues at hand are selecting the proper size series resistor to get the proper operating current and adding a parallel diode to prevent damaging the LED from excessive reverse voltage.   Typical LEDs can take 5-6 volts backwards without damage.  We're pushing our luck with our 6.3V AC source.  Since I didn't know exactly what LED I had I did a quick test.  I used a 1N914 diode parallel to the LED but reversed in polarity, this will shunt the negative portion of the AC wave and protect the LED.  I put a 1k trim pot is series with the LED/ diode and found about 480 ohms gave me the correct current and lit up the LED nicely.  Since the closest 1/4 watt resistor I could find laying around was 330 ohms I tried that, it made the LED a little brighter but OK.  The 1/4w resistor and the 1N914 are small enough to both fit within the barrel of the new pilot light assembly.  Remember when soldering up the LED to be gentle with your soldering iron and use a heat sink since its easy to cook LEDs.  Finally product looks great from inside and outside the amp and should be maintenance free.  Hope this helps.

Have you got the lights you were searching for? i need new pilot lights at affordable prices.. Please help with some suitable options..Waiting for reply thanks in advance:)