[BUILD] New FET/RACK Official Help Thread - Please read first post!

[sonority7]

Thanks Mike, see below for my results. Not sure how much is OK for my values to vary but it looks like maybe  my voltage at TP 15 is a little low and also my voltage for Q13 seems way low, everything else seems to be in the ball park as far as i can tell. My TP18 Q Bias readings were right on.

TP 1 = .07
TP 15 = 2.98
TP 17 = .595

Q2 - S=4.8, G=2.5, D=7.6
Q3 - C=15.8, E=7.0, B=7.6
Q4 - S=4.6, G=2.1, D=13.6
Q5 - C=26.2, E=2.9, B=3.4
Q6 - B=2.9, E=2.3, C=28.3
Q7 - C=15.1, E=4.1, B=4.68
Q8 - C=30.99, E=14.6, B=15.2
Q9 - C=17.9, E=2.99, B=3.56
Q10 - C=31.1, E=17.3, B=17.9
Q11 - S= -1.28, D=6.28, G= -1.29
Q12 - C=6.28, E= -1.3, B= -1.28
Q13 - C=2.74, E= -1.3, B=-0.68

TP 22
20:1 = .43
12:1 = .24
8:1 = .175
4:1 = .11

CR2
20:1 = 3.96
12:1 = 2.19
8:1 = 1.62
4:1 = 1.05

TP 21
20:1 = -6.0
12:1 = -3.51
8:1 = -2.73
4:1 = -1.95

 

[Echo North]

Seems like everything else is working fine.

You're able to get a 10dB drop at the output but just can calibrate the meter to it right?

Ya maybe let's send you a new pair of Q12/13.

Send us an email.

Mike

 

[Diamondj421]

Hey Mike!
I was going to send my Rev D back to you about a year ago to look over since it still had issues after my repair, but of course the problem magically disappeared as soon as I got the packing slip. If you recall, the meter had been teetering around the zero marker in GR mode without anything plugged into it. The issue remained at bay for quite some time but is now back with a vengeance.  Now it's completely pinned to the right when in GR mode. I've tried adjusting the trim on the front but it doesn't budge. However, when I choose +4 or +8 the. meter works perfectly fine. Thoughts?

 

[Echo North]

Hey Mike!
I was going to send my Rev D back to you about a year ago to look over since it still had issues after my repair, but of course the problem magically disappeared as soon as I got the packing slip. If you recall, the meter had been teetering around the zero marker in GR mode without anything plugged into it. The issue remained at bay for quite some time but is now back with a vengeance.  Now it's completely pinned to the right when in GR mode. I've tried adjusting the trim on the front but it doesn't budge. However, when I choose +4 or +8 the. meter works perfectly fine. Thoughts?

It's definitely a GR meter driver issue.  Is this an older wired build?  I would make 100% the 29/28 connections are secure at the main PCB and meter PCB.  The the wired connections with the zero adjust are secure.

Mike

 

[Diamondj421]

It's definitely a GR meter driver issue.  Is this an older wired build?  I would make 100% the 29/28 connections are secure at the main PCB and meter PCB.  The the wired connections with the zero adjust are secure.

Mike

It’s one of the newer ones. I’ll take a look. Thanks so much as always!!!

 

[Echo North]

It’s one of the newer ones. I’ll take a look. Thanks so much as always!!!

Hmmmm...must be a loose connection in there.  If we repaired it we warrantee our repair.

Mike

 

[Diamondj421]

It’s one of the newer ones. I’ll take a look. Thanks so much as always!!!

Mike,
You are a genius/legend in my book! Not sure exactly which component it was but I reflowed the solder on R28, R29 and the zero adjust and BAM! Back up and running. I'm going to get a Lola tattoo in your honor... jk.

 

[Echo North]

Mike,
You are a genius/legend in my book! Not sure exactly which component it was but I reflowed the solder on R28, R29 and the zero adjust and BAM! Back up and running. I'm going to get a Lola tattoo in your honor... jk.

Nice!

 

[sonority7]

Seems like everything else is working fine.

You're able to get a 10dB drop at the output but just can calibrate the meter to it right?

Ya maybe let's send you a new pair of Q12/13.

Send us an email.

Mike

Hey Mike, so actually I now have the meter working properly and the bias is set, so I'm really worried about Q12 and Q 13 anymore. It's just the following 3 readings that seem pretty off:

Output Trans BRN 2.38
Output XLR 2.34
TP15 2.98

I've checked everything in the signal pre and line stage. Any Ideas?

 

[Echo North]

Hey Mike, so actually I now have the meter working properly and the bias is set, so I'm really worried about Q12 and Q 13 anymore. It's just the following 3 readings that seem pretty off:

Output Trans BRN 2.38
Output XLR 2.34
TP15 2.98

I've checked everything in the signal pre and line stage. Any Ideas?

What do you get at the output if you turn your output knob up to the next dot?

We have new TPads that are less "hot" and the output pots have a large tolerance...everything might be ok.

Mike

 

[sonority7]

Thanks for your help Mike,

So the output values went up a bit but I'm not sure what's going on with TP15. It's now reading  (and i checked it 10 times)
TP15 = .6

It was consistently up at 2.98 the other day and I haven't touched it since.  The other values are:

Output Trans BRN= 2.9
Output XLR = 2.8

The unit works great though, sounds great, the VU seems to be working fine and is considerably louder on a DAW vocal track than when it's not inserted...

 

[Echo North]

Thanks for your help Mike,

So the output values went up a bit but I'm not sure what's going on with TP15. It's now reading  (and i checked it 10 times)
TP15 = .6

It was consistently up at 2.98 the other day and I haven't touched it since.  The other values are:

Output Trans BRN= 2.9
Output XLR = 2.8

The unit works great though, sounds great, the VU seems to be working fine and is considerably louder on a DAW vocal track than when it's not inserted...

Hmmmm maybe all it fine. Just a weird measurement/signal generator error maybe?

 

[Ali]

Hello,
Just finish assembling for 2 pieces of 1176 Rev D , 1 working as supposed to be after following step by step the guidance from Hairball site, the second one after I start the signal measuring input 0.775 VAC (troubleshooting Guide) , on the second stage (amplification) checking the TP1/TP15/TP17 veryyy veryyy low signal...
Referring to the coz of this problem from (Troubleshooting guide) checked the  Tpad, input transformer, Q1, Tpad fine, Transistor (Q1) working , transformer out (brown) signal was 5 point something.

Please help if anyone had this issue before or what u advice ( i have no idea about electronics) but soldering I consider my self on the professional side.

P.S  both pieces was assembled at the same time means whatever I put on the first I move to the second , as well an electronic guy checked the schem. With the PCB and all fine in term of component place.

Thank you

 

[Echo North]

Hello,
Just finish assembling for 2 pieces of 1176 Rev D , 1 working as supposed to be after following step by step the guidance from Hairball site, the second one after I start the signal measuring input 0.775 VAC (troubleshooting Guide) , on the second stage (amplification) checking the TP1/TP15/TP17 veryyy veryyy low signal...
Referring to the coz of this problem from (Troubleshooting guide) checked the  Tpad, input transformer, Q1, Tpad fine, Transistor (Q1) working , transformer out (brown) signal was 5 point something.

Please help if anyone had this issue before or what u advice ( i have no idea about electronics) but soldering I consider my self on the professional side.

P.S  both pieces was assembled at the same time means whatever I put on the first I move to the second , as well an electronic guy checked the schem. With the PCB and all fine in term of component place.

Thank you

Can you post your TP1/TP15/TP17/brown wire readings along with the same readings from the good unit?

That would help me a lot.

Thanks!

Mike

***I will be traveling Wednesday April 24th through Monday April 29th and will be slower responding during that time***

 

[Diamondj421]

Nice!

So as I said before, I reflowed those joints, the meter was working but now it's pinned to the right again. Any idea what could be happening?

 

[matt_weber]

I tend to get very intense cell phone interference when ever theres a cell phone near the 1176 and the phone is either in use or sending/ receiving  a message.  Obviously keeping the phones away from the gear is the first thing, but in case someone happens to be near it and I'm mid vocal take, whats the best way to shield the 1176 from this interference?

 

[Echo North]

I tend to get very intense cell phone interference when ever theres a cell phone near the 1176 and the phone is either in use or sending/ receiving  a message.  Obviously keeping the phones away from the gear is the first thing, but in case someone happens to be near it and I'm mid vocal take, whats the best way to shield the 1176 from this interference?

I've never come across this before.  The input TX is shielded and the enclosure is pretty shielded. Could it be more of a cabling issue or the output of what is sending to the FET/RACK?

Mike

 

[Echo North]

So as I said before, I reflowed those joints, the meter was working but now it's pinned to the right again. Any idea what could be happening?

Something is making intermittent connection. You may need to safely wiggle some stuff in that section and see where the bad connection is.

Mike

 

[Potato Cakes]

I tend to get very intense cell phone interference when ever theres a cell phone near the 1176 and the phone is either in use or sending/ receiving  a message.  Obviously keeping the phones away from the gear is the first thing, but in case someone happens to be near it and I'm mid vocal take, whats the best way to shield the 1176 from this interference?

This is/was a common problem with GSM phones near any audio gear and any tube amp in my experience.

Turn your/their phone off when tracking. It'll be way easier than implementing a shielding scheme to protect your audio gear from cell phone interference.

Thanks!

Paul

 

[sonority7]

Hmmmm maybe all it fine. Just a weird measurement/signal generator error maybe?

Would this be affecting the sound quality? I have nothing to compare it to so If it's just a low output I can deal with it. It seems to be working fine but I want it to be the best it can be and will send it in if you think it needs to be looked at.

Thanks!