1176 True Rev G No Output

Hi guys!

I built a Rev G hairball kit, when i measure from pin3 of input to pin3 of output i get 545ohms. The meter seems to work but in GR mode, the needle moves slightly, in all other modes the meter stays at -20.  :-[
Is this normal? As mentioned in title, i have no output, nor does the needle move when i feed a signal.

Thanks for any help!

Mattt

Well if you have no output I'd start there.  Have you been able to do the Qbias adjustment?

Hi mike,

The Q Bias Adjustment seems to do nothing. I have tested from the input pin 3 to the board and there seems to be connectivity. I was reading on here somewhere about balanced vs Unbalanced, just confused me more.

Thanks for your help!

Matthewd422 said:

Hi mike,

The Q Bias Adjustment seems to do nothing. I have tested from the input pin 3 to the board and there seems to be connectivity. I was reading on here somewhere about balanced vs Unbalanced, just confused me more.

Thanks for your help!

Click to expand...

If you measure between the CT of your power transformer, and Pad 18 do you see a DC voltage?  Does rotating the QBias change it?

Getting 0.06v across to pad 18, and yes it does change. Clockwise makes it go down, counter clock makes it go up.

Hey mike,

I know your a busy guy. Know of anything of the top of your head i can try?

I can read a schematic a little bit, just know nothing about whats going on inside.  ???

PS; I took the unit too a tech in my area, and he declined to work on it saying it wouldnt be worth his time hahahahaha
he said all the components were good, but i might check over again.

Thanks a ton for your time,

Matt

That is way too low.

Is your -10VDC rail testing out ok?

What are you DC voltage on either side of R82 and R83?  Both sided compared to ground.  No signal.

Why not use (and read) the dedicated 1176 help thread?

Jakob E.

Bingo!
-Figured out last night I had mixed up the Variable Resistor values, so i got them changed according too the schematic.

As of today: In GR mode my meter easily zeros with tweaking, but in +4 & +8 i get nothing still. I still have the output problem too. 

I'm so close i can taste it! (*hear)

* as for the voltage, Measuring from CT to the test points, i get 9.6vDC, and -29vDC....?? maybe im measuring it backwards or something

At R82 i get about 9.6v, R83 i get 0.00v. And finally from CT to pad 18 i have 0.00v DC..

Thanks for your guys' help

Matt

Did I read right, you have 500 ohms between pin3 input and pin 3 output?

I wouldn't think there should be any DC continuity between input and output jacks 

Well as of today i have ZERO continuity between input and output. I guess thats right because of the output trx.

Still have no signal coming through to the meter.

I get 2v DC when measuring CT and Pad 18 Still.



Im contemplating just selling the thing and staring over....

Cheers,

Matt

Matthewd422 said:

...
* as for the voltage, Measuring from CT to the test points, i get 9.6vDC, and -29vDC....?? maybe im measuring it backwards or something

At R82 i get about 9.6v, R83 i get 0.00v. And finally from CT to pad 18 i have 0.00v DC..

Thanks for your guys' help

Matt

Click to expand...

If you're getting +10v and -30v then you simply have the multimeter leads backwards.