SSL 4000E SL611E channel stand-alone racking...

Astuck · Apr 22, 2013

Hi Ssl Gurus,

I'm trying to rack 2x SSL 4000E channels from 1980 : SL611EW1080-TV-TR

I'm cheking the pinout (611G version on my files) and I have a blurry idea what the 7x 20-ways pin blue connectors are for... TR and Multiplexing ?

They are labeled : S68 - S69 - S70 - S71 - S72 - S73

And S21E (I can find this one in the channel pinout)

The motherboard is old enough to be built before MPX/Total Recall was completed so my questions are :

1/ Can I run the channel without CF82E03 card ( TR Multiplex Card ) nor the 7x 20-pins ribbon cables ?
What does the setting MPX/Bypass change ?

2/ Does someone could have the kindness to send me CF82E03 and CF82E12 schematics please ? Thanks in advance

3/ Just under the 82E03 TR card is the CF82E12, this card receives +18vdc (pin13), -18vdc (pin24) but can't find where goes the "ground" from pin12...

4/I also have a problem with no LED/no lights, every grounds coming from the leds seem to pass through S68-69-... 20pins connectors and as I have absolutely no 20pins ribbon cable connected, I guess my problem is there...or not.

5/PSU : my power supply made for this project is +18vdc -18vdc +12vdc +48vdc
+18vdc pins37,38,39
-18vdc pins48,49,50
+12vdc pins41,42
+48vdc pins34,35
Psu grounds Ov : 44,45,46
Did I miss something about the ground ?

6/Computer send and return (pins 28 and 29) : should I link them ?

7/When you switch a channel on without computer, what is the default mode (Record/Mix/VCA To Mon) ?

Thanks in advance for every tips or answers you could bring to this project.
Arno.

sintech · Apr 22, 2013

Hi, if you're racking the channel stand alone, you'll need to do just a few simple things.

The +11.5v supply (Logic Low) needs to actually be a 6.5v supply hanging backwards subtracting from the +18v rail, to provide the Logic Common (low) of +11.5. This rail powers the LED's also.

The module when powered has no default status, you simply need to feed Logic Hi (+18v) to the upper connector (Pin 60 for Mix or Pin 63 for Record) to order all elements of the channel.

The MPX jumpers need to be in Bypass, this looks to be the case, and you can ignore all the Blue connectors that relate to the multiplexer.

Link computer send and return.

That's about all that's needed to make the channel run, personally, I'd put the module into Mix mode, and float the channel, link the output of Matrix routing to the group amp input, this would give a nice output stage

Check Out the forum: http://forum.sslmixed.com/index.php

This is the main place for SSL tech fooling/DIY

Astuck · Apr 23, 2013

Hi Andy,
Thanks a lot for these answers !

When you say :

sintech said:
The +11.5v supply (Logic Low) needs to actually be a 6.5v supply hanging backwards subtracting from the +18v rail, to provide the Logic Common (low) of +11.5. This rail powers the LED's also.

Do you mean :
Positive of +18v -> motherboard +18v (pin37,38,39)
Negative of -18v -> motherboard Ov (pin44,45,46)
Positive of +6.5v -> motherboard +18v (pin37,38,39)
Negative of -6.5v -> motherboard +11v (pin41,42)

In this situation, my power supply (done 2 years ago) is wrong about the +11vdc.

My board for the +11vdc is populated with a 7812, so 2 options :
1/ Simple resistive voltage divider R1=100R and R2=120R
Vin=12v Vout=6.5v

2/ Add a second voltage regulator 7806+friends, after my board.

What would be the cleanest way ?

I guess it's very important to keep this +6.5v rail as close as possible to 6.5v, due to the design, if
the 6.5v rail fails, I'll fry all the logic components ? Should the +18v be disconnected if the 6,5v rail falls under +6,0v ? It tastes like a good idea.

About the phantom +48v, there's no push-pull swith on my mic gain pot and there's a -20dB pad
below the phase switch, So is it a permanent +48v ?

I'll mod my board as you suggested and keep in touch asap.

Thanks again for your help.
Arno

sintech · Apr 23, 2013

Hey Arno,

Here's a better description of the PSU arrangement. Al Smart (Smart Research) explained to me why it has to be this way, as the regulation would try to pull it back up.. heheh or something like that. It's also cleaner for the logic to run like this away from the console ground.

Any 6 volt supply should be ok, as long as it has an independent ground from all the other rails. When I first started tinkering with buckets running standalone, I just got an off the shelf 7v SwitchMode and connected it to +18v and that pumped 11.5v out of it's ground

You could trim your one, should be fine.

Only the Bipolar rails track to each other. All other supplies are independent, this is how SSL do it.

Yes, I bet you're channels are Ex-Danish Radio, they did the switched Mic pre modification, and your right, Phantom is always live.

Andy

PS: See Attached PDF