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Pioneer SX-1500TD lamp circuit - Printable Version

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Pioneer SX-1500TD lamp circuit - paxto - 12-19-2019

I'm working on a Pioneer SX-1500TD receiver and noticed that Ron Ramirez had posted a thread about his rebuild (a long time ago).  Hey Ron, or anyone else, can you help me on a problem I'm having with the lamps?

I replaced them all and everything worked fine, but then I accidentally shorted something and they all went out but the receiver is still functioning properly.  The lamps themselves are not burned out--theyr'e still good.  But I can't figure out from the service manual diagrams where the problem is.

RE: Pioneer SX-1500TD lamp circuit - KCMike - 12-20-2019

Hello and welcome. If you have not found the problem yet follow the blue wire that comes out of the transformer.
It will go to a terminal strip right next to the transformer. There is a glass fuse there covered in plastic and soldered in.
You could use a jumper wire across the fuse to see if the lights start working.

RE: Pioneer SX-1500TD lamp circuit - paxto - 12-20-2019

Late last night (after posting) I found that fuse.  I don't think it's on the schematic, so I was surprised to find it.  It was indeed blown, and using jumpers the lights indeed came on.  Soldered it in this morning and everything seems to be working.  Except the STEREO INDICATOR itself, but I'm not really worried about that.

Thanks for your confirmation.

RE: Pioneer SX-1500TD lamp circuit - Ron Ramirez - 12-20-2019

You can get the manual for that receiver here:

https://www.hifiengine.com/manual_library/pioneer/sx-1500td.shtml

You have to create an account to download (it's free).

The stereo indicator lamp not working could be caused by one of two things: either a burned out bulb, or a problem with the receiver's FM MPX decoder. Does it receive FM broadcasts in stereo?

RE: Pioneer SX-1500TD lamp circuit - paxto - 12-20-2019

Yes, it's receiving stereo FM very well.

RE: Pioneer SX-1500TD lamp circuit - Ron Ramirez - 12-20-2019

Ok. As I recall the lamp is incandescent, so you have to do one of two things: one, replace with an identical incandescent bulb; or two, replace with an LED but you will have to add series/parallel resistance to make the MPX decoder "think" it is incandescent.

Or do as you mentioned and just leave it alone. I would not do that, however - I would want a working bulb.

RE: Pioneer SX-1500TD lamp circuit - paxto - 12-20-2019

thanks