Bumblebee Q4 Emitter voltage

[chongmagic]

I am getting 8v on the emitter where is should be around 5. All my other voltages per the build docs are correct. I am not getting any swell effect, and turning the mix knob fully CCW yields no sound. I am going to check my soldering around that area. But I am guessing getting around 8 volts at Q4 E is the problem area?

Sent from my SM-N975U using Tapatalk

[madbean]

Are you sure you don't have them labeled backwards? Q4 is the one on the lower half of the PCB and Q5 is at the top.

Then again, you shouldn't be reading 8v on either of those emitters!

[chongmagic]

Sorry I meant here is where I am getting 8v

Sent from my SM-N975U using Tapatalk

[madbean]

No worries. Okay, that's the base of Q4. So, R26 is connected between V+ and Q4 base which is what creates its bias voltage. A reading of 8v there means you might have actually put in something other than a 1M resistor.

If you look at the trace diagram in the doc you'll see the 1M just below the two .47uF caps that are next to Q4. Double check that resistance. If it is 1M we'll see what else might be happening.

[chongmagic]

It is hard to tell but there is a 1m there.

Sent from my SM-N975U using Tapatalk

[chongmagic]

Also I am getting .825 volts instead of 8 I misread last night. Around 8 volts is coming into R26 and .8 coming out.

[somnif]

It is hard to tell but there is a 1m there.

Sent from my SM-N975U using Tapatalk

It looks like Brown-Black-Black-Gold to me, are you sure that third band is green?

[chongmagic]

This is it, but I am going to replace it with another one.

Sent from my SM-N975U using Tapatalk

[chongmagic]

So I replaced R26 with another 1M still .8v at the base could the transistor be bad?

Sent from my SM-N975U using Tapatalk