[BUILD] 1176LN Rev D DIY

[sr1200]

push em all in, it works (not as easily as an old 1176 cuz the switches are made better now) but it certainly works.

 

[TheWolfman]

This is an S.O.S call....

Still unable to get any movement on the meter when trying to set "Null Adjust" for the second calibration step.

"Q Bias" Adjust went without any problems.

???

 

[100WChris]

Hi!
I´m looking for the heatsink for Q6, i live in germany and the "normal" suppliers dont have the TO5-snap on heatsink listed in the BOM. I only found a smaller heatsink with 44 instead of 34 KW. Is this enough? Or does anybody can make a suggestion where to order the correct heatsink (without paying 20€ shipping cost...).
Thank you very much for any replys! Sorry for my bad english :
Chris

 

[Stagefright13]

Any TO5 heat sink will work. Q6 gets hot but is well withing the temp spec of the part.

John

 

[100WChris]

Cool (in the true sense of the word )
Thanks John!
Chris

 

[TheWolfman]

This is an S.O.S call....

Still unable to get any movement on the meter when trying to set "Null Adjust" for the second calibration step.

"Q Bias" Adjust went without any problems.

 

[earth tones]

Wolfman.....just to clarify, you are stuck at the very first step of the the Discrete Meter Circuit calibration:  unable to zero the GR meter using R71...with shorting plug inserted to take R44 out, meter in GR mode?

 

[Ilya]

This is an S.O.S call....

Still unable to get any movement on the meter when trying to set "Null Adjust" for the second calibration step.

"Q Bias" Adjust went without any problems.

Check that you have -10V at the other end of R76. Also check the voltages around transistors and compare them against the reference voltages in mnats pdf. Confirm that you have the voltage changing at the base of Q13 when you turn the trimmer.

 

[pittsburgh]

I believe that my unit is not compressing and that it's not a meter issue. I have checked for audible continuity between the ratio pin 3s and haven't found an issue. I have my 1176 rev d in a harball case and don't see any drop in level when turning the compression on or off using the attack pot. For kicks I shorted pad 22 to ground, like the video said, and my meter pegs to +3. When that happens I can set the level to -10, using the input knob. When I go for the next round in calibration I find that I don't have enough pot left to set the level back to 0 and get the desired -10 level when pad 22 gets put back in the circuit.

  Two questions here. Why am I seeing a change in +4Vu when I short pad 22, but not when I engage the compression? Where should the trim adjustment pad be set at?

  Thanks as always,

  -P

 

[pittsburgh]

Just double checked all of my wiring around the attack and release pots and the corresponding runs to the PCB and ratio board. Everything looks good.

 

[number2]

I'm looking for 22 awg stranded hook-up wire  that is appliance wiring material (awm). I'm confused if I have the right thing because this Belden wire is over $30 and mnats page says $5. Anybody got a link for the right stuff?

 

[sr1200]

http://www.mouser.com/Wire-Cable/Wire-Single-Conductor/_/N-5ggs?P=1z0wxmfZ1z0juksZ1z0vt0d&Keyword=hookup+wire&FS=True&Ns=Pricing|0


You can go to Radio Shack or someplace similar for stuff as well... they just dont have all the colors.  And for this project, i suggest color coding the wires... makes troubleshooting a LOT easier.

 

[Dr Gris]

Hi there,
I' m gonna change my R12 from 920 to 1.8k for greater headroom.
While I' m at it I thought I should also change out my R15 and R64.

MNATS page says:
R15 Value on overlay should be 6.8k rather than 7.5k
R64 Value on overlay should be 1.5k rather than 2.2k

Mine has R15: 7.5k and R64: 2.2k.

I'm so very new to this and was just wondering how the circuit will benefit from these changes?

Kind regards
Magnus

 

[sr1200]

there was a misprint on older revisions of the board.  The R12 is also a mis-print and should be 1.8k.

 

[Dr Gris]

Thanks.

That´s what I thought. Though I must say it sounds great, even with the wrong values.
Like I said, I understand the R12 change, but R15 and R64 I don' t, yet

Magnus

 

[Brotastic]

Ok, this is a really newbtastic question, but I just want to make sure I am doing this correctly.  On C7, C10, and C17 on the Mnats 1176 RevD 2.2 board there are 4 holes for each location and the Panasonic 1uf cap has only two legs.  I am assuming that I can use any of these wholes to put the legs in as long as the polarity is correct (the two holes on the positive side are positive and vise versa).  If it needs to go in a certain way....(reading the wholes from left to right, right being the positive position) hole 1 and 3 or hole 2 and 4 please let me know. 

Also, I assume I don't have to populate the power supply if I bought the PSU boards for running two main boards in stereo?  I just have to run leads to the psu boards from the main boards. 

Thank you for your patience with my newbness. 

Dan

 

[Ilya]

Ok, this is a really newbtastic question, but I just want to make sure I am doing this correctly.  On C7, C10, and C17 on the Mnats 1176 RevD 2.2 board there are 4 holes for each location and the Panasonic 1uf cap has only two legs.  I am assuming that I can use any of these wholes to put the legs in as long as the polarity is correct (the two holes on the positive side are positive and vise versa).  If it needs to go in a certain way....(reading the wholes from left to right, right being the positive position) hole 1 and 3 or hole 2 and 4 please let me know. 

Also, I assume I don't have to populate the power supply if I bought the PSU boards for running two main boards in stereo?  I just have to run leads to the psu boards from the main boards. 

Thank you for your patience with my newbness. 

Dan

Multiple holes are there to accommodate different capacitor footprints. Make sure that you solder the cap so that it's legs are not shorted since some holes are connected together (you may see it or check with a dmm).

Don't stuff the PSU section in case you're using external one.

 

[Brotastic]

Thanks for the reply. 

If anyone knows:

I am using the Mnats psu.  I am trying to search for the semi conductors lm337 and lm317.  Well, in Mnats website (http://mnats.net/psu.html) he states the voltage regulators need to be 24 volts.  I can not find a lm337 nor a lm317 with the output voltage of -/+24 volts.  They are all -/+ 1.2 V to 57 V!!!

Am I reading something wrong? 

I appreciate your help.

Dan

 

[Brotastic]

Ok, I read it again.....and I think he is talking about the psu on the main board.  If anyone wants to confirm that ....it would ease my mind. For the 100n monolithic cap, does anyone have any suggestions.  I am having a hard time locating one.  Thanks.

 

[sr1200]

you may have to do some math converting nf to uf or pf depending on how the manufacturer decides to label it.  VERY easy part to find.