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So built a DBT today. My question is on the wattage of the bulb to use. Is it the output wattage? I have a 75w bulb in the socket now and when I initially power on the receiver the bulb lights up until the relay clicks on and then it goes out. I also checked all the transistors on the F2856...

So I am testing D04 with my DMM set to diode mode and get 1.44V. Reversing the leads I get OL. At D03 on the left channel I get 1.23V and OL.

Looks like i'll be building a DBT this weekend.

@Hyperion should I be testing the bias with speakers attached and volume at 0? That is how I have been doing it.

For the right channel that would be D04 which is a STV-4H varistor. Can that be tested on the board? I read a post http://www.audiokarma.org/forums/index.php?threads/replacing-the-stv-3h-and-4h-diodes.279530/page-3#post-9149822 on testing the STV-4H but I think it's beyond my abilities right...

@Hyperion I am testing it according to the instructions in the service manual by clipping the leads from my DMM to the pins in Figure 2.2. This is how I adjusted the left channel and it responded as expected. The odd thing is that the pot I took off the board did have some adjustment range to...

Well since I ordered that single turn 220Ω pot before I read all your comments I couldn't stop it and it arrived today. So since I have it I decided to put it in. The spec is 4.5 mV ±1mV and I am getting 23 V. Adjusting it has no affect on the bias voltage. I have two of them so I think I may...

The trimpots that are on the board now are single turn. I guess having the 25 turn pot makes for finer adjustment?

That's what it was. Thank you.

Well shoot. I jumped the gun and ordered 220Ω trimmer. https://www.mouser.com/ProductDetail/531-PT6KH-220 Looks like it is lower quality than what you linked to.

It's definitely bad. I'm getting 560Ω through it and it should only go up to 220Ω. Sucks that I'm going to have to spend $8 for shipping on a 50 cent part.

It's hard to get a good photo but VR6 is charred in the center. Not sure what to order. the parts list shows 3 stock numbers. There is only one side adjust through hole 220ohm trimpot I can find at mouser...

OK I was able to set the output voltage at the speaker terminals to 0v for both the right and left channels by adjusting VR1, VR3, and VR2, VR4. Why does the Service Manual say to adjust both trimpots for each channel? I was able to adjust the bias for the left channel to 4.5mv by adjusting...

Well before I read your comment I replaced all four OTs. I also deoxed all buttons and knobs. Now I have sound! Although only out of the left side. The right side is really hot. If I turn the balance all the way left it sounds great. With balance in the center the right channel is...

Thank you John @Hyperion I purposefully did not replace the bad output transistors yet because I assumed that the relay was bad because it is not clicking when I turn the stereo on but the that does not seem to be the case now. I'll replace the output transistors now and see where that gets me.

I actually have 54.5v on the cathode side.

Thank you John. I had it backwards! I'm trying to learn and I really appreciate the information! I will check this tonight.

Since the relay does not click when I turn the power on I need to make sure it is getting power. With power on I should be getting 49v at pins 79 and 80 if I am reading the schematic correctly. Those are on the output side of the relay I believe. However I cannot tell from the schematic where...

I saw someone on Reddit post this website today for A/V centers. Neat looking stuff. It's a European website but maybe they have an American warehouse. https://www.made.com/storage/media-unit

I received my transistors and have new thermal paste to apply to the film when installing the new parts. Do I apply the thermal paste to both sides of the film? Also, in reading about other issues with the G-6000 I read a thread about checking to make sure the relay clicks when you power the...

@dlucy What did you clean the boards with? What did you lube the push buttons with? Did you also deoxit the pushbuttons? thanks. Awesome thread.

@DirtyDog how's the refurb coming along? I'm starting one and interested to hear what kind of issues others have had.

I ordered two MJ21194G NPN and two MJ21193G PNP.

Even though that resistor was scorched the resistance was good. 219.6Ω for a 220Ω resistor. So now I just wait on my new output transistors to arrive and all will work again!