CurtPalme.com Home Theater Forum

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

Okay mac, here's one I haven't done anything with. This is a VSX-50 that works perfectly fine, except it overheats...

I've only used the front 2 speakers, none of the others, so I don't know if the other channels would get hot as well if hooked up. It took about 5 minutes of listening to it, and I felt the heat pouring out the top of the unit on the far right side of the heatsink. I shut it down so it wouldn't fry or anything.

Where shall we begin? Very Happy

**Curt Palme** · Posted: Mon Jul 01, 2013 2:14 pm Post subject:

Where is the heat coming from? Output transistors? Check the bias on all output channels to start.

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

Yep it's coming from the outputs, the rest of the unit is cool as a clam. I'll get the service manual and check the bias out.

I'm starting to gather a database of manuals and schematics from all of these damn things Neutral

**Curt Palme** · Posted: Mon Jul 01, 2013 2:38 pm Post subject:

Unless it's a vintage amp worth $$, mine get 1/2 hour tops. Smile

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

Well I paid $12 a piece for each of these 30 A/V units, so they'll get a bit more of my time than they probably should. I did get a few newer higher end denon units and a Marantz as well. Those ones need some work too but I figured I would give mac a break on the Denons for a while Razz

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

That receiver uses those piece of sh*t STK's for power amps. Is the fan running? That heat may be normal for those crap things.

Disconnect all inputs and outputs and run it for a while and then feel each of the 2 stk's and see if one is any more hotter then the others.

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

Are you sure mac? I'm looking at it and it doesn't have a fan, and the outputs are sanken discrete, not those STK integrated POS's that some other pioneers use (got one here that looks like it went through a compactor with them in it, and it has a fan)

Sure you didn't pull some other manual? Razz

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Pioneer VSX-50?

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Hmmm, looks like Pioneer had an older VSX-50 6 channel one. Yours is the Elite I suppose. Can't find a manual yet. Do you have one?

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

Yep its the Elite VSX-50, network, HDMI etc...

Just to add, the rest of the channels do not overheat, just the front channel(s) I haven't verified if its one of the front channels or both yet.

I haven't looked for a manual yet, I'll let you know if I do though.

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

I believe I have the correct one now, just not sure if it's exact. That should have overheat detection. Put a thermometer on top with the 2 fronts playing at normal low volume and let me know the temp.

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

Will do mac, just to let you know, it is the Front Left channel, I tested by hooking up one speaker individually, all channels work perfectly except the front left, even when not playing, just having a load on it makes it get hot. If I unhook the speaker from it, it will cool back down.

Do you want me to do the temp test with the speaker hooked up to the front left?

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

If you have it narrowed down to the left channel then don't bother with the temp test. Let me check a couple things.

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Ok, now this is assuming I have the correct manual. I couldn't get the exact VSX50 elite one but I got the VSX1021k which is suppose to be the same. But if I tell you to check somewhere or something and you don't have it then we will have to improvise.

So, does your receiver have test points, TP404 and TP402? They should be 3 pad test points.

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

Yes it does

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

Yes it does

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Ok, with nothing connect to any inputs and no speakers connected, set your DMM to DC volts, unit turned on and test between pads 1 and 3 on both test points. Actually you might as well check all channels, TP404, TP402, TP403, TP401, TP405, TP406 and TP407. let me know the readings.

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

SOrry I didn't get back to you yesterday mac, I had to empty out the kitchen and get this place somewhat ready for the 4th.

I checked all the test points and every one of them reads 0.000mv exact. I have to admit, that's a bit impressive for me since most the time when I'm checking the dc mv its never perfect.

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

well ok, it said that because I didn't realize that it went into protection while I was testing those points mac. Which is a first for this receiver. It does it whether or not im poking around in it.

While it was turning on though, I did check the TP for the front left channel and it read 4.0mv, I haven't checked the other channels yet, I will, does the relay for the amplifier need to click on ?

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

I think we're going to have to pull the amp out to continue on this, everytime I turn it on it either says "AMP ERR" and goes to protection, or "AMP OVERHEAT" and goes into protection.

So I can't really test power anymore