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

[bieckmusic]

Great, thanks so much.  Just want to make sure.....


bless, greg

 

[MicDaddy]

Thanks Mike for that read, I'll do some investigating with how I have it mounted, and also possibly DC blocking on the power cord. 

Really it is a non-issue, just wanted to be sure. 

 

[dustbro]

Hey Mike,

Should I expect any (very slight) mechanical 60Hz from the toroidal?  

I have the same thing from the hairball toroid. Everything else works fine, so I guess all is ok

 

[MicDaddy]

(tried to post a photo of the shootout but it's telling me the 'uploader is full contact admin')

Rev A in the studio paired against the UA 2-1176

Both 1176s sound Fantastic!  Very similar compressors, me and my buddy were trying to describe differences, and really it was like comparing two bananas.  Both are bananas and taste like bananas, but maybe this one is a tad more green, and this other not as green.  

The rev A has this low end grit when really smashing, a distortion that I keep describing as 'bite' it grabbed my voice and yanked it out of my throat with a real gritty throaty warmness.

 

[bieckmusic]

I just finished up wiring my REV A.  Before I power it up, I'm going through everything and double checking my wiring... 

I have one question:  I have 2 wires left unconnected from the output transformer.  I'm using the Hairball supplied transformer and every connection is used except for the yellow and orange wire??
I must have missed something, but I've looked over the wiring pages for the Output section and it says match the wires with the markings on the board (v 2.5 Mnats) 

Also, I have a spare capacitor.  A 6.8uF electrolytic.  ???

I'd sure appreciate any thoughts, I'm nervous about plugging this labor of love in with a few loose wires back there.


bless, Greg

 

[MicDaddy]

Tie the orange and yellow together, you'll find it on a wiring diagram somewhere...   ;D

Not sure about the 6.8uF, that sounds suspect, be sure that your entire board is populated correctly, if parts ordered vs pcb population correlate with the BOM figure out how you ended up with the extra cap.

over here ended up with an extra wima, heatsink, and 47uF electrolytic...  (order errors on my part)

 

[bieckmusic]

Thanks, you're right.  I looked at the schematic and they are tied together.  I'm going to power it up today, so excited!  I did power it up last night and it did not smoke or anything...  But I pulled the power chord and when I plugged it back in the fuse blew.


So off to get a new fuse, and I'm going to tie the transformer ends together.


I'll keep you posted.  This is so fun!!!!  So grateful for everyone who has worked so hard to make this possible!

bless, greg

 

[MicDaddy]

btw, this may not be by the book but I upped the rating of the fuse, thinking mouser originally sent me a 250mA slowblow.

Mine did the same thing, power up fine, power down immediately power back up and pop.. 

(actually spent a good amount of time troubleshooting the damn fuse)

 

[bieckmusic]

Really, that's interesting, what fuse type did you actually settle on?  My machine is quite a fuse popper.  At first it stayed on for a few minutes.  Now it just pops as soon as I apply the juice.  Radio Shack only had fast acting  .315 amp fuses so thats what I got...

While it was working it seemed like it was happy...

 

[bieckmusic]

WOW    I can't believe it.  After giving up, and blowing 6 fuses the unit powered up and sounded great (thought not sure if it's compressing or just acting like a mic pre)  It ran for hours  several times with out any problem.  Though whenever I turn it off and then try and turn it back on half of the time it blows a fuse.  Seems like if I have all the gains down and attack off and ratios out it does a little better though.


I haven't done the meter calibration.  But I did notice that in GR meter mode, the meter sits at the bottom instead of around 0 where it should be....

At least I heard some sound, and it was beautiful.  Anyone have any thoughts on the fuse issue, I would be very appreciative.

Greg

 

[Echo North]

Make sure you're using slow blow fuses.

 

[MicDaddy]

the fuse I stuck in mine is a 500mA slow blow.
Thanks for the clarification Mike

Greg,

Regarding the meter in GR mode.  Mine was very similar, in GR mode it would peg +3 in the red until I managed to complete the 'Q' bias calibration correctly  :  

Perhaps it was all three calibrations, but I'm sure once the 'Q' bias was set it stopped pegging in the red.


Try Menards/Lowes/Homedepot etc for fuses   

 

[bieckmusic]

A big thank you to everyone for this wonderful project. My 1176 is working and sounds amazing! We put it up in the studio where I'm working on a Daryl Hall solo record and my engineer friends were excited by how cool it sounded. I noticed that it really excelled on bass guitar and it was incredible on acoustic rhythm guitar.

 

[rhythminmind]

Following the current "wiring guide"
It suggests this for the VU lamp

Powering the lamp at around 11 Volts seems to give a decent glow.

So 30.4V - 11V = 19.4V. We need to drop 19.4 Volts across the resistor.

19.4/.089 = 217.99. So we need a value of around 217 Ohms for the resistor. Choosing a value close to that we settle on a 240 Ohm 5 Watt resistor.

Does the current Hairball/mouser BOM supply this or an equivalent resistor?

 

[Echo North]

No it's not in the BOM because originally people could opt for the LED meter.

I should add it.

Any local electronics store should have one.

 

[rhythminmind]

Thanks for the quick reply. I won't have a problem getting one (still waiting for the PCB'c anyways), just wanted to make sure I wasn't missing something. Everything else it wired up nicely.

 

[rhythminmind]

Will these do the job?
http://www.mouser.com/ProductDetail/Xicon/286-240-RC/?qs=sGAEpiMZZMvmQ%252bOLa8n%2fM8NxniUM25cDz6fsog3x9LQ%3d

 

[Echo North]

yes

 

[SmitH]

Hello.
After hours of trouble shooting,  i thought it was time to ask for some help.

I have a REV-A V1.2  wired up. I'm using the 2N5088's for Q3, Q5, Q7-10 (using the altenate base pad). It passes audio fine, but no compression.

I'm having trouble calibrating the unit. (Step one Q bias) (0.775v 1K sine) when I bring the input control up, I can't get the meter to read higher than -7.
Increasing the output control (from 3/4 to full) doesn't make a huge difference. When I turn the Q Bias trimmer, the meter moves, but I still can't get it above -7.

I've double checked the wiring, all seems to be correct.
Just thought maybe someone could point me in some sort of direction.
Thankyou.

 

[MicDaddy]

SmitH,

I found a link (cannot find it for the life of me) where the calibration is done with only a signal and a DMM.  
(ok found it, was a 404 not found but look in the google cache)

This is how I have mine setup
http://www.google.com/url?sa=t&source=web&cd=1&sqi=2&ved=0CB4QIDAA&url=http%3A%2F%2Fwebcache.googleusercontent.com%2Fsearch%3Fq%3Dcache%3Ar7yhgI6lJnsJ%3Animbleswitch.com%2Fdiy%2F1176_revD%2Findex.php%253Fpage%253Dcalibration%2Brev%2Ba%2Bhow%2Bto%2Bknow%2Bwhen%2Bq%2Bbias%2Bis%2Bset%26cd%3D1%26hl%3Den%26ct%3Dclnk%26gl%3Dus%26client%3Dfirefox-a%26source%3Dwww.google.com&rct=j&q=rev%20a%20how%20to%20know%20when%20q%20bias%20is%20set%20&ei=ucBOTaO3MpC4sQP2k5n6Cg&usg=AFQjCNFj6I5Hpr8xvzx7iyo1x7zlMtY0KA&sig2=cVOnaCkHI8IIhGUSz-kwsg&cad=rja