Need Obsolete Display Lamp or Cross-Reference

Ogrebelle

Hey guys, I am looking for a now obsolete lamp to repair a blown display on a Yamaha RX-950 2-channel stereo receiver (circa 1991) that I have owned since new. I really, really love this receiver and want to repair the display. The original Yamaha part # for the lamp is VH471600 (I believe they may have later substituted part # VE628900 but can't fully vouch for that) but is now obsolete. Per Yamaha, the bulb specs at 14.5 v and 115 ma. It is a small 2-lead lamp of approximately 4.0 mm in diameter. The lamp is clear and utilizes an amber silicone(?) lamp cap for the display color and mounting (insert) flange. I can't find anything like it anywhere. I stopped by a long established local electronics repair shop that works on a lot of older and higher end equipment, in addition to modern stuff, (and is an authorized Yamaha repair shop) and they gave me the closest thing they could come up with although I don't recall the specs at the moment and it is still in the unit (it was a bi-pin lamp that they soldered leads to) which I installed but it only lasted for about 8 seconds or less (a decent bull ride) by going bright, then dim, then dead upon initial startup. The lamp's input power tests out per the service manual's specs so I'm not concerned with that. The unit is mint and has never had any problems of any sort. Does anyone have something that will work or can point me in the right direction with a supplier, part #, workaround, alternative, donor part, etc.? Obviously, I don't want any workarounds or modifications that could fry something on the unit itself. Thanks for your help!
Doug

delkal

Ogrebelle wrote: »

Per Yamaha, the bulb specs at 14.5 v and 115 ma.

I would look at car lights. People think they are 12 volts but when running in a car they can get to 14+ volts easily.

You need a low watt bulb (like used for the Speedometer/ inside dash). And that milliamp draw means it is just a 1-2 watt bulb.

You will have to figure out how to modify the leads.

FestYboy

Amber LED. Add current control and you're ready to go.

Ogrebelle

LED current control is a bit beyond me... unless someone were to give me a schematic. I can solder and follow diagrams. Also, would an LED and all that goes with it have a negative impact/interference on audio quality? Probably looking the traditional route with my limited experience in LED modifications.

mhardy6647

Usually just use a resistor to limit the current knowing the voltage and current specs for the LED and Ohm's law.
https://www.sparkfun.com/tutorials/219

F1nut

Here ya go, he'll get you squared away.

https://sites.google.com/site/dgwojocom/

There's another guy that specializes in incandescent bulbs for vintage gear, but I can't remember his site. Check on AK.

Here's another possible option, but not the guy I was thinking of.

https://www.jkllamps.com/specialty/vintageaudio

Ogrebelle

dgwojo got it handled, quickly, and it's on it's way ($8.50 shipped). Can't wait to get it installed and the display working again. Thanks everyone for your input!

While we're at it, one more question that I wondered about when I had it opened up last time. While I'm inside again should I do anything to clean it up? While it has always been racked and protected I was a little surprised by the amount of dust that has made its way through the top vents onto the electrical componentry. I guess considering it is 28 years old I shouldn't be that surprised. Should this be cleaned or just let it ride for fear of messing up something else that works just fine? If to clean, how? Vacuum, compressed air, electrical spray cleaner, etc.?

Maybe this should have been a new thread?

F1nut

Blow out the dust, which acts like a blanket. Make sure it's unplugged first.

pumpkinman

Way to go F1 !!!