NE2 neon lamps for turntable strobe

[62vauxhall]

This Toshiba turntable I got a couple of weeks ago had a very dim strobe lamp and once removed, the blackened/silvered inside surface explained why. It is also friggin' huge compared to some NE2 neon bulbs I have. I've played around with an NE2 trying different resistors to see what difference in brightness might be achieved. The resistor used for the original bulb is 15K and what is recommended for an NE2 is 100K. I've tried about 6 different values between those two and there is a perceptible difference in brightness as the resistance get lower. Not substantial but noticeable. To achieve a brightness closer to what the original bulb produced when in good condition, the thought occurred of using two NE2's in parallel. There is enough room inside where the original bulb was housed. The voltage feed is AC house current. If I were to parallel two NE2's and use a single 35K to 60K resistor, would this work?

 

[orange]

This owners' manual PDF file has the schematic that should show you the values in the strobe circuit:

http://www.google.com/url?sa=t&rct=...Ax5JzLZR0GFLhjHQgdvadw&bvm=bv.148747831,d.cGc

 

[62vauxhall]

Well so much for that idea. Seems that two NE2 bulbs won't work simultaneously in parallel. One lights up very briefly, goes out then the other turns on. Oh well, a single it is then.

 

[Gepetto]

Well so much for that idea. Seems that two NE2 bulbs won't work simultaneously in parallel. One lights up very briefly, goes out then the other turns on. Oh well, a single it is then.

They will if you feed them each with their own resistor from the AC line...

 

[orange]

You know that if you look hard enough you can find good neon lamps in parts listings...I see one for SL-1950 that in a pinch I could probably use on one of my other Technics but for the fact that it's pretty darn stable and I can see the dot pattern well enough without it.

 

[orange]

Since it sounds like the old assembly may have had some silvered lining scorch or melt behind the lamp from what you described I would also think about relining it and seeing how warm the thing is getting at the correct values.

Would that be it, there is a chamber that encloses it and maybe mirrors the light onto the platter?

 

[orange]

Lt. Columbo here, just one more question, sir, if you would...

Is it possible that a previous owner attempted to replace that lamp after the first one blew and maybe damaged the assembly as you see it now, and that they might have used a dimmer light?

I don't know, it's only a hunch, are there other grades of these lamps that resemble the correct one?

 

[62vauxhall]

They will if you feed them each with their own resistor from the AC line...

(knee slap) Now he tells me!

A single NE2 with a 36K resistor worked out pretty well. It's bright enough to illuminate the strobe in a lighted room and I'm happy with that.

 

[62vauxhall]

Lt. Columbo here, just one more question, sir, if you would...

Is it possible that a previous owner attempted to replace that lamp after the first one blew and maybe damaged the assembly as you see it now, and that they might have used a dimmer light?

I don't know, it's only a hunch, are there other grades of these lamps that resemble the correct one?

The lamp I pulled out has been in there since day one. I saw high intensity NE2's offered online but since a single regular one works well enough, I'll stick with it. There's a local shop I go to first if I'm trying to replace an obsolete part. They have NOS (very OS actually) of a lot of things and they did have a neon lamp of the correct size and shape but the wrong voltage. Too bad because it would have been a near perfect fit. As it was, with a combination of shrink tube and a piece of small diameter hose, I got the small bulb jammed in the pylon well enough and in the correct position.