[BUILD] 1176 Rev A - Back to the beginning...

[regularjohn]

Hey guys!
I'm currently assembling a Rev A, and I just got the Hairball kit for it.  It didn't come with any documentation on the output transformer and I can't seem to find a definate wiring guide for it.  I've been searching through the forums with no luck; sorry if this is already documented somewere.  Any help would be much appreciated!  Thanks

 

[Rob Flinn]

Hey guys!
I'm currently assembling a Rev A, and I just got the Hairball kit for it.  It didn't come with any documentation on the output transformer and I can't seem to find a definate wiring guide for it.  I've been searching through the forums with no luck; sorry if this is already documented somewere.  Any help would be much appreciated!  Thanks

You don't really need any documentation.

The primary connections are marked on the pcb by lead colour, which leaves you with 4 unattached wires.  2 of these are red & blue, use them for your output & connect the remaining 2 together (cant remember their colour off hand).

 

[Echo North]

connect the remaining 2 together (cant remember their colour off hand).

Orange and Yellow.

Mike

 

[stereokillah]

you do like this wiring guid plus join the yellow and orange together

PISTURE ERASED CAUSE WRONG

 

[ilfungo]

hello and thanks Rob
The strange thing is that I have tested the compressor for a week and it worked very well,
I have now mounted in the case and I have the problem that you said
could be a wiring problem?
thanks

 

[spica]

All,

*Just a quick note about the wiring diagram above*

The labels for the output transformer are incorrect.  Ilfungo, that is why your resistor burned up.  I had the same problem.  Check Mako's documentation for the correct transformer wires to the board.  The labels on my board were covered up by my screw connectors, so I used the above diagram... which had them incorrect.  I don't recall what they should be off hand but the labeling in Mako's .pdf is correct.

Cheers

 

[stereokillah]

hi spica , could you explain exatcly what's a problem on this wiring, cause it's seems to be same color as the colr on the pcb, if the hairball tx used the same color of the cinemag the output tx is good on this wiring.

I ask it cause , it's my wiring guide i'm benginer and nobady give me an aprovment about it and my unit isn't finished, i will modified it before make it on work.

thanx

 

[stereokillah]

ok i ffind the problem the grey and black are inversd on this diagriam i'm soory about it.
someone tell me it's same like rev d but on my board this two color are not in same place.

it's right for you?

 

[ilfungo]

Thanks Spica!!!
The problem was the output transformer connection...
the last problem is the spdt wiring
I did as suggested Eddie, but when switch pot
off  the compression is active (less
but active)...
Is it normal?
Thanks

 

[stereokillah]

ilfungo  your problem of connection is about the position of the grey and black wire?

 

[regularjohn]

Much thanks!  Haha, the answer was right in front of me all along!  Story of my life  ;D

 

[stereokillah]

this is the new one i'm sorry about it

 

[ilfungo]

"ilfungo  your problem of connection is about the position of the grey and black wire?"


Hello Stereokillah
as a  5002 (Hairball), I simply complied with the colors on the main board
and everything seems to work well ...

 

[ilfungo]

hello guys
you know where I can find a potentiometer ( 2k long shaft pot)  for zero adjust like this?
Mouser code?
Thanks

 

[Rob Flinn]

hello guys
you know where I can find a potentiometer ( 2k long shaft pot)  for zero adjust like this?
Mouser code?
Thanks

You should look maybe at extension shafts for regular pots as an alternative.

 

[muffy1975]

;D Ok here as some questions that I can't find a basic answer to. If anyone can find the time to answer these questions it would be of great help!!!

1) How to fit the 2n5088's in place of the 2n3707's. I notice that one of the pcb  feet is connected to the alternative pcb foot in the semi-circular space for the transitor. Do I put that leg of the transistor in the alternative pcb footing? or not? Non tech answer if possible :

2) How do you connect the alternative external PSU to the main board? Has anyone got a picture of how they have done this? Which parts do you leave out? Is it all of the parts in the main PCB PSU corner? I have built the G1176 with the alternative PSU but the layout is different!

3) Why has everyone used those GIANT 1uf capacitors. Can I use the smaller orange 100v 1uf caps instead? They are belgian caps?

Many thanks in advance if anyone finds the time.

 

[diyfanatic]

I think you can use what ever you want, just pay attention to the voltage...
but it's absolutly forbidden to use Belgian caps... ;D

 

[Rob Flinn]

;D Ok here as some questions that I can't find a basic answer to. If anyone can find the time to answer these questions it would be of great help!!!

1) How to fit the 2n5088's in place of the 2n3707's. I notice that one of the pcb  feet is connected to the alternative pcb foot in the semi-circular space for the transitor. Do I put that leg of the transistor in the alternative pcb footing? or not? Non tech answer if possible :

I don't know what the answer to this is but you could probably work it out yourself if you download the data sheets for both devices.

 

[regularjohn]

Here's what might be a stupid question...and if it is, I apologize:  
When doing the q bias adjustment, why do you use a .775V input signal to set 0VU when metering in +4?  Shouldn't you use a 1.23V input signal, since 1.23V is +4?

Also, I'm having a hell of a time getting the meter to calibrate in GR mode.  Has anyone else had problems with this?  It's like there's not enough turn on the trimmers, and I've been trying different value trimmers and it just won't work.  I'm not a newb...I'm very meticulous when I build and follow the schematics to a T.  I test all my components before I solder them in.  I've never had this kind of problem with a DIY build before.  Don't get me wrong...the comp works and sounds great.  The ratios seem to be right on.  I just can't get the meter to work in GR mode.   ???

The weird thing is that GR mode worked when I initially used 2n5088's.  But the 2n5088's didn't pass audio, but I could zero the meter - there was no actual compression happening though because there was no audio.  So I switched to the 2n3708's because of orangerec having a similar issue, and viola!  Works and sounds great.  But now the only thing that worked with the 2n5088's doesn't work with the 2n3708's.  And they are the ONLY thing I changed.  WTF?  ???  If anyone has any insight, I'd be massively appreciative!

BTW, I'm wondering if I have an older version of the rev a pcb, because I don't have spots for the optional components to build the 1108 preamp.

 

[Rob Flinn]

Here's what might be a stupid question...and if it is, I apologize:  
When doing the q bias adjustment, why do you use a .775V input signal to set 0VU when metering in +4?  Shouldn't you use a 1.23V input signal, since 1.23V is +4?

e

Setting the Q bias, does not really have anything to do with the level that the meter shows.  The +4dB setting scales the output of the 1176.  Setting the Q bias is used to set the point of conduction of the fet.

Also, I'm having a hell of a time getting the meter to calibrate in GR mode.  Has anyone else had problems with this?  It's like there's not enough turn on the trimmers, and I've been trying different value trimmers and it just won't work.  I'm not a newb...I'm very meticulous when I build and follow the schematics to a T.  I test all my components before I solder them in.  I've never had this kind of problem with a DIY build before.  Don't get me wrong...the comp works and sounds great.  The ratios seem to be right on.  I just can't get the meter to work in GR mode.  ???

The weird thing is that GR mode worked when I initially used 2n5088's.  But the 2n5088's didn't pass audio, but I could zero the meter - there was no actual compression happening though because there was no audio.  So I switched to the 2n3708's because of orangerec having a similar issue, and viola!  Works and sounds great.  But now the only thing that worked with the 2n5088's doesn't work with the 2n3708's.  And they are the ONLY thing I changed.  WTF?  ???  If anyone has any insight, I'd be massively appreciative!

BTW, I'm wondering if I have an older version of the rev a pcb, because I don't have spots for the optional components to build the 1108 preamp.

I have had terrible problems calibrating the meter with this circuit.  It helps if you have matched the fets.  But even then sometimes I've found that if I swap the meter & gain reduction fet it enables me to calibrate the unit, when it would  calibrate the other way round ????