GSSL HELP THREAD!!!

[Stagefright13]

OH I see. They are the cans from back in the day? I heard they sound better to some people. Sorry maybe I didn't backtrack the thread far enough. But leaving the trimmer at midpoint should be good if you don't have a distortion analyzer. And you can always use your ears as I do! :wink:

If it sounds good it IS good is my moto! I'm not an expert tho so don't take my word for it.

 

[Stagefright13]

MartyMart just connect the grounds to star ground at the power transformer.( toothed lock washers at the power transformer can, paint or shellac coating removed also linked to iec ground) I don't use the xlr tabs for anything and so far so good. No hum. Pin 1 on xlr goes to star ground. Check my project photos. It always has worked for me. Typically inputs only, adding output's linked to pin 1 may cause ground loop. I will say again I am not an expert...

 

[karl j]

Thanks again John. For now I'm gonna leave the 50ks as is. I'll worry about calibrating the side-chain instead.

Also, still need to get that meter working, as well as getting some audio to the left output.

I did some looking last night, and think there might be a bad trace on the control PCB between point "G" and the "meter -" hole. More investigation is needed. As well as the time to do it!

 

[Stagefright13]

It's easy to bridge a trace on that board with solder so look careful. I changed the resistor value for the meter to use a Beringer style one lemme check what I used.,..

 

[Stagefright13]

check this thread:

http://www.groupdiy.com/index.php?topic=17

But I think I adjusted it verses a 1k sine wave and my large resistor supply...

I'll look some more and tell ya what I used.

 

[karl j]

I don't think it's a solder bridge, I think there is a flaw in the PCB. I was reading signal at "G" on the control board, but nothing at the "meter - " hole (which is where the "G" connects to). I think the trace on the PCB is bad. No biggie, it's an easy fix (if that's indeed my problem).

As for the meter..... I originally had a 12k resistor in there, cuz I must've read on one of these threads that that's what was required. So I swapped it for the 2k as per the PCB. No difference, but that's cuz it's a different problem (see above).

What value resistor dod you use for your B- meter?

 

[MartyMart]

John, thanks for the tip, I'm using stereo jack sockets which are not insulated.
They are all grounded to the case at sleeve, Just powered up finally and it works
fine and so far no "hum" or treble loss

Meter/Threshold/Ratio/Attack/Release and Bypass all work fine.

Just one problem, the "Makeup" pot seems to do nothing at all so far, I'm only
testing with a DI instrument and NOT across a stereo mix as yet ( it's late ! )
Perhaps the "makeup" will come into play on some heavier stereo input.
I was expecting more of a "gain" or "output" control, perhaps I have that wrong.
Or it's a "duff" pot.
EDIT _ EDIT - Just noticed the makeup pot is grounding against the front
plate of the rack case .... will fix that !!
Marty.

 

[MartyMart]

Makeup pot is bad, ( cheap alpha 16mm) will change it tomorrow.
MM.

 

[vertiges]

[quote author="MartyMart"]
Perhaps the "makeup" will come into play on some heavier stereo input.
[/quote]

No. The "makeup" is active all the time. (Except in bypass)

eD))

 

[MartyMart]

[quote author="vertiges"][quote author="MartyMart"]
Perhaps the "makeup" will come into play on some heavier stereo input.
[/quote]

No. The "makeup" is active all the time. (Except in bypass)

eD))[/quote]

I realized that I was being a bit "dumb" on that one
Pot swopped and all good
I used too thick "hook-up" wire and it stressed the pots connections too much.
Great compressor BTW !!
MM.

 

[vertiges]

[quote author="karl j"]What value resistor dod you use for your B- meter?[/quote]

You shoud use a 5k trimmer.
The Beh*ringer is not very accurate / linear. However it will give you a very good idea of what is happening.
It has been intensively discussed in this (long) thread. :wink:

I calibrated mine to be exact at -10 dB of reduction.

eD)))

 

[vertiges]

[quote author="karl j"]I ran all my LEDs off the "power on" spot on the control PCB. Everything powered up fine. LEDs were plenty bright.
[/quote]

Please someone confirm as I'm not totally sure on that one :roll: .
I don't think it's a good idea to "suck" current for illuminating 3 leds from that point. Isn't it better to take it "pre-regulation" ?

eD

 

[gyraf]

If you use the LED's in series, you still only sink the same amount of current. You will know when you draw too much current, when the 78L12 regulator gets too hot and shuts down (or if you get an annoying hum in the unit when the LED's are lit)

A better place to grab power for LED lightening is at the 1000uF reservoir capacitors (make sure to use a suitable series resistor)

Jakob E.

 

[karl j]

Yeah, I know that wasn't the recommended way to light the other 2 LEDs. I had to try it anyway. They did light up and I didn't have any buzz in the audio, but I will change it to make it better. It seems it will be easiest to take the power right from the transformer secondaries, find a suitable resistor and connect the meter light and bypass light in series (or would it be parallel) to it.

 

[vertiges]

And... sometimes in series, you won't have the same "brightness impression" for all the leds. That's why I like to use trimmer resistors.

eD

 

[safe as milk]

hi
my 7815 keep frying itself with no ic's or vca's in there.
just wondered if anyone had this before & could point me to a
potential test point for sorting it out.

thankyou very much
justin

 

[vertiges]

Hi Justin,

What are your voltages measurements ?

eD)))

 

[karl j]

Got my left channel audio back, also got the meter working ( but not calibrated).

However, I seem to get a LOT of compression. Gotta check the ratio. Also need to calibrate the super side-chain.

 

[karl j]

Also, blew my meter light. Was gonna wire off of the Tranny secondaries. I found what I need to do to drop the voltage to about 10volts (AC) checking with my meter. I connected the meter light via alligator clips (without the resistors) and fried the meter light.

Ooops.

Glad I bought a spare.

 

[vertiges]

karl,

Did you put the 47k resistor on the leg of the threshold pot ?

eD)))