Issue with gr meter reading 1176 rev a bluestripe

[elephantlanestudios]

Hi guys,

This is the first time I post and also the first time I build my own gear.

I got to the end of the build, and I have a couple of issues.  I tried to look throughout the forum but couldn't find anything. Here is my problem.

The output pot seems to be reversed (dims clockwise). I tried reversing the non ground cables on the pcb but still have the same problem.. Any ideas?

Main issue: I can't go through with my gr meter calibration cause it doesn't seem to move at all.. Qbias seems fine, a can see the gr drop while metering the output and turning on compression, but I can't see the gr meter moving at all, dead on 0.

Would appreciate any tips!

Thanks in advance

Mike

 

[mitsos]

The output pot is reversed.  Swap the wires on the two outer pins. Signal goes from the preamp to the CW pin, out the middle pin to the output amp, and the CCW pin goes to ground.  When you turn the pot fully CCW, you want to be grounding the input of the output amp. 

The GR meter problem is somewhere in the GR meter driver circuit.  When in +4/+8 the meter is connected to the compressor output, seeing movement there means the meter is working.  When meter switch is in GR the VU meter is connected to the driver circuit.

 

[elephantlanestudios]

Hi mitsos, thanks for the prompt reply!

So if I invert the output pins nothing should affect the other pots am I right?

With the meter I'm not sure what I'm doing wrong.. It's wired as follows:

Xy output

28 29 go to the driver

Vu goes to meter

Is it right? The thing is doesn't the original 1176 meter the input?

Posting a pic of the driver

Thanks for your patience

Mike

 

[mitsos]

Can't really help you much with the meter, it's been a while since I built some RevD's (which I think use the same meter circuit as the RevA).  But if it's working in +4 and +8 but not in GR, then it's a problem with the GR circuit or the wiring between the GR circuit and the meter.

For the output pot, just to make sure we are speaking the same language, check this link:
http://sound.westhost.com/pots.htm

Look at figure 5, then look at figure 6 and wire it like a volume pot.

 

[simonsez]

Hi mitsos, thanks for the prompt reply!

So if I invert the output pins nothing should affect the other pots am I right?

With the meter I'm not sure what I'm doing wrong.. It's wired as follows:

Xy output

28 29 go to the driver

Vu goes to meter

Is it right? The thing is doesn't the original 1176 meter the input?

Posting a pic of the driver

Thanks for your patience

Mike

I saw you put 3M9 for R67 instead of 3K9