Stubborn EQ problem RE: 242 & 292

[Druhms]

I've recently acquired Skip Saylor's old 4K. It's had the "controversial" dip in the ultrasonic bath to clean it up.  I was told it was brought to spec, but I am learning that was probably a ploy by the "broker" to make me drool...
Regardless,  one of my many problems:
   There are several channels, that when engaged, fail to pass signal when the HPF is on.  If I twist the HPF to the Off position, it will pass audio.  No amount of frustrated twisting and jabbing at buttons will fix this problem.  Is this a technical problem, or the result of an older console with gritty connections?  I haven't pulled the channel out to look at any obvious issues, and besides, I am an infant as far as any skilled "techy" knowledge is concerned.  Willing to learn though.
Any suggestions?
JJ

[TheMixfactoryNYC]

The easiest thing to do is to pull out the EQ card out of one of the channels that has a HPF that passes audio and switch it for one that doesn't.

If you get signal on the channel than its the EQ card.

If you still don't get audio it could be a bad HPF switch but that is rare.

[brewery]

are you talking about the 100 channel G? that's the largest 4k i know of..

[Artur D'Assumpção]

Hi,

I also agree that the fast way to isolate the problem is to switch EQ cards.

If the problem is indeed the EQ card can be simply fatigued capacitors or dead opamps. I would suggest is that you put this channel in a channel extender and probe with an audio probe. You'l eventually find out where the audio stops and you should have found the problem area.

With an older desk like yours I would also be entirely re-capping channels and the center section. Most of the time fatigued capacitors can be guilty of most of permanent and intermittent faults/misbehavior.

Fortunately these desks are a workhorse and very well engineered. You'll be always able to repair and bring it up to specs, depending only on the amount of money and time you have in hand. The most tricky part might be the computer if it is not working properly. Most of the times you'll only be able to solve this issue replacing it with other cards.

Cheers,

Artur

[Artur D'Assumpção]

Also,

Sometimes the console is put up to specs, which means fixing problems and calibrating everything accordingly to SSL factory specs. That doesn't mean you are exempt of any faults happening, specially after decommissioning and recommission which is very stressful for the console. Disassembling and reassembling all the electronics always give some problems to these consoles.

Also it seems that the local power rating might also have some influence on the console initial power up. The voltage level is always different from place to place, which seem to be cause for most of the flaws appearing during commissioning. Anyways, from talking with some qualified techs, after a while of fixing these initial issues the console tends to stabilize.

My console was fully refurbished "top to bottom". It's like a new console. And even so when it was commissioned there where a few issues that had to be fixed at the spot and a couple of other issues that developed a few days after commissioning. Now it's all stable and working fine! (powering up and down every day)

Cheers,

Artur

[Druhms]

Hello,

Thank you for all of your replies.
So, are the filters not part of the eq cards? The filters are independent of the eq cards?
Regardless, is there some way I can learn some basic tech skills to at least trouble shoot such problems?  I'm quite handy with a soldering gun and have an elementary understanding of components that make up a signal chain.  I live in a town that barely has a guitar amp tech. Are there some youtube videos someone could recommend?  The last thing I want to do is drop several grand on The Desk Doctor to fly over and spend a top dollar week poking around my board telling me how much more money it will take to get it trust worthy
.
Here are some typical issues I have with my console:

--I'll send an identical signal to 2 different channels, and find drastically different output levels with the identical eq's set identical. Sometimes I'll find identical output if eq is removed...but sometimes I don't.
--Everything from above, but substitute the Dynamics instead of the EQ.
--Some meters don't work. Where can I find replacement meters?
--I would like all of my meters to light up. Right now about 8 are lighted. The led's all work though.
--A couple channels are straight up dead. Do not power on at all. I've tried pulling the channels and reseating them in different slots. No luck.
--Aux send levels are not all the same send level.

There are more problems, but I don't want to bore you to death. 
Can any of you recommend a competent tech in the South East region of the United States?  I'm in North Florida.
Thanks for the help!
JJ

 

[Artur D'Assumpção]

The SSL is not hard (although complex piece of engineering) to get a grasp with when you start putting your hands into it. It's something you will not understand all at once, but rather piece by piece while you learn and deal with each module.

Do you have all the service manuals and extender cards? This will help greatly understand and troubleshoot.

You shouldn't panic and go piece by piece. You'll eventually endup with a 100% working console. Start with simple things, for instance by learning and fixing one channel strip. After you feel comfortable you can eventually do all of them.

Do you have an idea when this console was last recapped? Fully or only the center section?

If you're seriously interested in getting this console to work properly and reliably and to last you should think of slowly recapping the entire console, if this hasn't been done anytime recently (5 to 10 years). I would start by finding the faults and taking the opportunity to recap entirely the faulty cards (note down which ones you have recapped, put a sticker on them with the date). Then, after the console's all working I would start by recapping entirely the center section and calibrating it and all channels 1 by 1.
 
This is something that takes lots of time, so you have to reconsider either you do it or you hire a qualified tech to do it. Also you should have the correct tools to do it properly. If you don't have the proper solder station, a desolder gun it's very easy to do more harm than good. These old PCB boards can easily damage the solder eyelets or tracks while desoldering components.


To your specific case, it will be hard for us to help you in all your problems at once in one thread. What I would do is:

- open an excel spreadsheet and put all console channels in there (1-48?)

Now test thoroughly ALL channel strips: EQ, Dynamics, Routing Matrix, Echo Sends, faders, etc. Note down every issue you find per channel strip.

Do the same for the center section.

Then you must prioritize the issues and post 1 by 1 here. We will do what we can to help you troubleshoot and fix the issues. Just don't flood us with issues. Post only 1 and lets concentrate on that one. After that one is fixed, lets go to the other, until it's all done.

To start fixing stuff I would also get the following stuff:

- A good multimeter (fluke?)
- An audio probe (you can do it with a guitar amp)
- An osciloscope (it's not mandatory)
- A good solder station
- A desoldering station (this is the preferable and safest)... or desolder wick and desolder pump.

Finally you should order from mouser a bunch of components. You will need ICs, resistors and capacitors that are most commonly used across the console. ICs and capacitors are the more easy, since there are only "a few". Resistors are more tricky since you can find all types of values. What I did was inspect a series of cards diagrams and got a sorted mix of components. Mark as already shared a good list for the capacitors which you could reference, specially if you're going to recap the entire console.

If you need a list of ICs and Resistors I can give you also a few that I used.

I hope this gives you a good head start! Good luck!

Artur

[Druhms]

Artur,
Thank you for your response and suggestions.  I do have every intention of getting this thing up to 100%, or reasonably close.  I have all of the tools except an extender card. I'm guessing an extender card would make this undertaking much easier.  Another thing I am not familiar with are resistor values, IC types (brands?), cap values, etc...  I'm sure once I get into a channel, I can find this information as I go.  But, if you have a list of common parts, I would be most grateful.  I do have schematics.
I believe the center section was recapped and refurbished. That is what I was told. BUT, at times, I will have intermittent audio and popping on my Left side. I'll crank up the level on the Snare channel and pan it hard left and blast it through.  This leads me to believe the Center Section may not be as "Refurbished" as I was told.  I specifically inquired about specific Center Section G upgrades to the E Center Section, and all seemed to check out...on the phone.  I have a feeling these upgrades were actually done since it came from Skip Saylor....but how long ago?
Anyways, I have a mix to finish. But right after, I will start pulling channels.  And, find an extender card.
Thanks again,
JJ

[Druhms]

P.S.  Earlier, I misread the EQ Card suggestion. For some reason I was thinking the Filters were separate from the EQ Card.
P.P.S. Brewery, No, it's not the giant 100 ch beast.  I believe it was the one prior. It has 48 mono (32 - 242's, 16 - 292's), 4 stereo 242's, 8 ch bucket empty. RH 112 point PB (A bit odd, and cramped!)  Built 1987.

[Artur D'Assumpção]

Hi JJ

This is the Bill of materials made by Mark regarding capacitors:

http://forum.sslmixed.com/index.php?topic=308.msg4303#msg4303

Regarding ICs and Resistors this is what I have so far and have worked for me. I am sure there will be more stuff that you'll need, but this is a good heads up for common components that you will find on your console (all bought from Mouser):

Resistor List:

"Resistance
(Ohm)"   "Tolerance
(%)"   "Power Rating
(W)"   Voltage Rating (V)   Element Material   Case Style   Mounting   Manufacturer   "Manufacturer
Reference"
10   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-10-RC
22   1%   0,50   300   Metal Film   Axial Leaded   Through Hole   YAGEO   MFR50SFTE52-22R
22   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-22-RC
68   1%   0,60   360   Metal Film   Axial Leaded   Through Hole   VISHAY - MRS25 Series   MFR3 100R FC
100   1%   0,40   200   Metal Film   Axial Leaded   Through Hole   WELWYN - MFR Series   SFR2500001000FA500
100   1%   0,40   250   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   MRS25000C5609FCT00
100   1%   0,50   350   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   SFR25H0001000FR500
100   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-100-RC
649   1%   0,40   250   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   SFR2500006490FR5
649   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-649-RC
1.000   1%   0,25   300   Metal Film   Axial Leaded   Through Hole   VISHAY - RN Series   MRS25000C1201FCT00
1.000   1%   0,50   350   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   MRS25000C6809FCT00
1.000   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-1K-RC
1.200   1%   0,60   350   Metal Film   Axial Leaded   Through Hole   VISHAY - MRS25 Series   SFR25H0001001FR500
3.900   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-3.9K-RC
5.100   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   YAGEO   MFR-25FBF52-5K2
7.500   1%   0,50   200   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   SFR16S0007501FR500
7.500   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-7.5K-RC
10.000   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-10K-RC
10.700   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-10.7K-RC
15.000   1%   0,50   200   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   SFR16S0001502FR500
15.000   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-15K-RC
22.100   1%   0,50   200   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   SFR16S0002212FR500
22.100   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   YAGEO   MFR-25FBF52-22K1
36.500   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-36.5K-RC
47.500   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-47.5K-RC
53.600   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   YAGEO   MFR-25FTE52-53K6
68.100   1%   0,50   200   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   SFR16S0006812FR500
68.100   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   YAGEO   MFR-25FBF52-68K1
100.000   1%   0,50      Metal Film   Axial Leaded   Through Hole   KOA SPEER   MFS1/2DCT52R1003F
100.000   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-100K-RC
10 M   5%   0,50   250   Metal Film   Axial Leaded   Through Hole   VISHAY BC COMPONENTS   594-5053DM10M00JT
10M   5%   0,25      Metal Film   Axial Leaded   Through Hole      
10M   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   YAGEO   MFR-25FTE52-10M
1M   1%   0,25   250   Metal Film   Axial Leaded   Through Hole   XICON   271-1.0M-RC


ICs - Logic Gates

4572   TEXAS INSTRUMENTS   CD4572UBE   DIP-14   CMOS HEX Gate - Four inverters, One 2-input NOR gate, One 2-input NAND gate
4069   TEXAS INSTRUMENTS   CD4069UBEEE4   DIP-14   HEX Inverter
4016   TEXAS INSTRUMENTS   CD4016BE   DIP-14   CMOS Quad Bilateral Switch
4093   TEXAS INSTRUMENTS   CD4093BE   DIP-14   CMOS Quad 2-input NAND Schmitt Triggers
4081   TEXAS INSTRUMENTS   CD4081BE   DIP-14   CMOS Quad 2-Input AND Gates
4023   TEXAS INSTRUMENTS   CD4023BE   DIP-14   CMOS Triple 3-Input NAND Gates
4071   TEXAS INSTRUMENTS   CD4071BE   DIP-14   CMOS Quad 2-input OR Gates
4025   TEXAS INSTRUMENTS   CD40725BE   DIP-14   CMOS Triple 3-Input NOR Gates
4013   TEXAS INSTRUMENTS   CD4013BE   DIP-14   CMOS Dual D-Type Flip Flop
4010   TEXAS INSTRUMENTS   CD40106BE   DIP-14   CMOS Hex Schmitt Triggers
4001   TEXAS INSTRUMENTS   CD4001BE   DIP-14   CMOS QUAD 2-Input NOR Gates
4050   TEXAS INSTRUMENTS   CD4050BE   DIP-14   CMOS HEX/Buffer converters
4042   TEXAS INSTRUMENTS   CD4042BE   DIP-14   CMOS Quad Clocked "D" Latch
4011   TEXAS INSTRUMENTS   CD4011BE   DIP-14   CMOS Quad 2-Input NAND gates
4077   TEXAS INSTRUMENTS   CD4077BE   DIP-14   CMOS Quad exclusive NOR gate

ICs - Transistors

J112   Fairchild   J112   JFET N-Channel Switch

Hope it helps,

Cheers,

Artur

[Clip6]

Florida tech- Ross Alexander cell phone 786-385-5754

[Druhms]

Thank you, Artur, for the parts list!

And, thank you Clip6 for the lead on a Tech!

JJ