All things G1176 - the new "repost" thread.

[ChrioN]

Gyraf: you were 100% right. My unit works great btw :thumb:

 

[ChrioN]

My 1176 is now calibrated and works fine. I'll post some pics when I get a nicer looking front panel.
Until then, here is a filmclip of the vu meter in action. (I've not installed the light yet).

The movie is compressed with Xvid. Windows media player is recommended for viewing. Filesize: ~2.5mb :green:

http://hem.bredband.net/b237697/vu.avi

:sam:

 

[API]

Hi.

The only part i am now missing to complete my Mnats G1176´s is the 1N4740A diode.
Does anyone know where i can find one Sweden/Europe??
I have tried the usual places but have only found them in the US so far.

Thanks,
Dennis

 

[gyraf]

..that one isn't present in the G1176 - look at the old layout for reference..

 

[Jim50hertz]

[quote author="API"]Hi.

The only part i am now missing to complete my Mnats G1176´s is the 1N4740A diode.
Does anyone know where i can find one Sweden/Europe??
I have tried the usual places but have only found them in the US so far.

Thanks,
Dennis[/quote]

PM me an address and i'll send you one

 

[API]

Now I am a bit confused!

..that one isn't present in the G1176 - look at the old layout for reference..

Was this directed to me??
The part is on the Mnats BOM.

Will PM you Jim.

Dennis

 

[gyraf]

Might be the 10V Zener? In Europe we do not have christian-names for the individual voltages like the US-people..?

 

[W DeMarco]

I have a Q on my 1176,

I noticed that it has no bottom end compared to my Gssl. I figure its such a difference that something must be wrong. I changed to the same wiring that the ssl used out of the patch bays and still had the problem. I also noticed this same occurence on my almost finished Passive tube EQ. Again used known good wiring and the same problem. Has anyone encountered this problem. I tried searching the forums but can't find anything.
Thanks
Will

 

[gyraf]

probably a balanced/unbalanced issue. gssl is electronically balanced, where the g1176 is transformer balanced.

 

[lumpylipton]

Hi,

I have completed my 1176, and it is passing audio, and I was able to set the Q-bias. However, my unit does not appear to be compressing. Looking through the troubleshooting guides here, all my voltages look fine, and my DC voltages are changing at point 21 with ratio changes. However, they are not changing at point 7. They jump a bit when I switch ratio, but then they settle back to -1.3VDC. Also, my VU doesn't work in GR mode (it goes nowhere near 0VU and the zero and tracking doesn't appear to do anything). The VU works fine in output mode.

Any tips on where to start looking?
Thanks,
Warren

 

[bubba_b]

All of a sudden, my 1176 stopped working. It was fine, then the next day, nothing. Here's the problem:

I can see the unit getting input signal and the meter reacting to it, but the output is inaudible. If I crank up the volume on my monitors and set In & Out to full, I can barely hear signal and it is compressing. Any ideas?

 

[gyraf]

..output stage and output transformer..

 

[Holger]

[quote author="lumpylipton"]Hi,

I have completed my 1176, and it is passing audio, and I was able to set the Q-bias. However, my unit does not appear to be compressing. Looking through the troubleshooting guides here, all my voltages look fine, and my DC voltages are changing at point 21 with ratio changes. However, they are not changing at point 7. They jump a bit when I switch ratio, but then they settle back to -1.3VDC. Also, my VU doesn't work in GR mode (it goes nowhere near 0VU and the zero and tracking doesn't appear to do anything). The VU works fine in output mode.

Any tips on where to start looking?
Thanks,
Warren[/quote]

Same with my 1176. At point 7 I read -1.414V. No compression, passes audio, VU works (quite well) for output. Maybe someone here can give us a hint...please...

 

[mata_haze]

Hi everybody,
I just got my second 1176 ready to be calibrated (the first one is up and running).
I do have a question regarding it which came up while I was trying to set right Q bias.
this is what I have got:
with the unit in bypass mode I can see on my scope a distortion (only on the negative side of the sinewave) when the input pot is set on a position less than half.
so I traced it back and that distortion appears on the input stage right after the input pot on the Drain of the first FET Q1.
all the static voltages look perfect (referred to Jackob scheme) but I can't push the input gain more than 1/4 otherwise this weird distorion appears.
I tried paying about with the Q-Bias settings, but of course that just changes the level at which the distortion appears, but it does not fix it..
any suggestion anyone?
any help will be much appreciated.

BTW= I am using OEP IN and OUT trannies.

 

[ChrioN]

I've just built a fully working G1176, the problem is there is too little gain. I'm using a lundahl input transformer and a JLM111DC (wired as 1:2) output transformer. Even when the output pot is turned fully CW there isn't enough gain for the AD's on the soundcard. The input on my soundcard is turned to +4dBu btw..

This isn't even one bit higher gain than with a OEP output transformer.

This is how I hooked up the output trannie:

This problem was solved with the R26 mod: http://www.groupdiy.com/index.php?topic=21491

 

[gyraf]

there should be plenty gain. could be the fet gives too low threshold - see earlier posts about this.

Jakob E.

 

[ChrioN]

There is plenty gain and then some, but only in -10dBv in -10dBv out...but not with +4dBu in and out.
Seems like it starts to compress too early. Is this a "Q bias" issue?
The compressor is useless with input pot turned 12 o'clock or further. Way too much compression

 

[emtee]

Look here for posts about resolving the G1176 threshold problems...

http://www.groupdiy.com/index.php?topic=646&postdays=0&postorder=asc&highlight=threshhold+threshold+trim&start=1140

 

[muz]

I have a similar type of problem as previous posts...but a little different...
Ive fired it up...everything seems to be working...but I cant hear any compression...
By working I mean...It passes signal...the VU shows the out signal in +4...after tweeking the trim pots, It shows gain reduction in GR mode...and according to the VU the ratio push buttons and attack and release pots work as they should...

Just no compressed audio signal from the xlr output...

So This should make it easier to isolate prob..?

Im using lundahl in and out, mnats rev j and pushbutton boards...

Im a tad green and could do with a couple of hints on this...

Ive been reading heaps of posts...and initially wondered if my imput signal was too low...cause i had to give it heaps of signal to get the GR to meter and set the trims in hard right and left respectivly...
But the more common problem is too much from the input...can I use the same kind of sidechain/trimpot to fix this?

I suspect it could be the same/related prob..?

please help me on my way...

 

[gyraf]

Just no compressed audio signal from the xlr output...

So This should make it easier to isolate prob..?

Most of the circuit is working correctly - only you have a problem with the FET at the audio attenuator, or the components just around it.

Jakob E.