SSlmixed.com Forum

Tech discussion => 4K,6K,8K Series => Topic started by: Rick Carson on January 27, 2013, 05:46:48 PM

Title: Dim button stopped working properly
Post by: Rick Carson on January 27, 2013, 05:46:48 PM
Say I have the mini knob up and the dim knob lower if I press the button there is no changes in volume it doesn't Dim. Also now the dim knob drops the volume if I turn it down without the dim knob pressed down volume still goes down.

If I press the dim knob the monitor cut still pops up the red monitor cut light in the master section.

Just no more dim.

As some one who mixes with the dim button pushed down I would like the feature back!
Title: Re: Dim button stopped working properly
Post by: sintech on January 27, 2013, 06:59:13 PM
Problem is on the 82E24 card, The Dim circuit is based around T4, bet if you change that, it'll be back :-)
Title: Re: Dim button stopped working properly
Post by: Rick Carson on January 28, 2013, 04:32:24 AM
Thank you! I have te replacement part ordered. So I have a pretty noob question. I would like to recap my desk and have ordered the caps to recap the whole desk. I would like to know the best way to remove the cards for recapping. Brute force does not seem to be the route to go :)
Title: Re: Dim button stopped working properly
Post by: Matt Sartori on January 28, 2013, 08:50:45 AM
Thank you! I have te replacement part ordered. So I have a pretty noob question. I would like to recap my desk and have ordered the caps to recap the whole desk. I would like to know the best way to remove the cards for recapping. Brute force does not seem to be the route to go :)

the cards are fitted on the main PCB board through a multiway connector and held in place by a scre fitted from the back of the main PCB.
if you flip the channel on its back you'll see the screw going through, remove that and slide the card out, job done!

hope this helps.

Mattia.
Title: Re: Dim button stopped working properly
Post by: marcmozart on February 01, 2013, 02:46:54 PM
Just wanted to say I love how people help each other on this forum. Great spirit!!! http://forum.sslmixed.com/Smileys/default/smiley.gif
Title: Re: Dim button stopped working properly
Post by: Artur D'Assumpção on February 01, 2013, 04:55:02 PM
This is a great community! :)

With these types of initiatives and good will, vintage SSLs will last a lifetime! :D
Title: Dim button stopped plus community spirit!
Post by: jimlfixit on February 01, 2013, 09:23:01 PM
Hi people. First of all, nothing from me about Dim switches ... I'm just commenting on the last few grateful posts.

Thanks to Mattia for starting this off in July last year, we are fast heading for 1000 posts with 105 users so far. This is certainly a good community to date and is solely concerned with SSL matters. This site is better than GearButts, Groupie DIY (sorry, me being sarcastic) plus others in dealing with SSL consoles and will most certainly become the place to visit for all serious technical issues involved with SSL's in the future. There are some very dedicated people contributing to this forum along with a large batch of new users.

Let's all keep the SSL legacy alive. Hopefully soon, SSL, their distributors, dealers and interested parties will contribute as well ....?
Title: Re: Dim button stopped working properly
Post by: Jermbob on February 06, 2013, 10:11:54 PM
I've got the same thing happening to me. Should I replace all four t4 transistors on that card? Any idea where to purchase these?

Any help would be greatly appreciated! :)
Title: Re: Dim button stopped working properly
Post by: sintech on February 06, 2013, 11:30:53 PM
T4 is an IC, some sort of Quad Op-amp, the Dim circuit uses all four parts of this, and really the only other active component is a transistor. It uses very little else.

I don't actually have a 82E24 card to check the exact part, just working off the service manual.

Maybe some one has a good picture of the 24 card??
Title: Re: Dim button stopped working properly
Post by: Jermbob on February 07, 2013, 01:02:28 AM
That made it easier. The part is 4069. I'm assuming this ic will do: http://www.amazon.com/NTE-NTE4069-4069-IC-CMOS/dp/B0002FRF06

Thank you sintech!  :)
Title: Re: Dim button stopped working properly
Post by: xmax on February 07, 2013, 01:04:36 AM
Rick don't just go recapping the whole desk all at once, recap one card at a time testing them before and after
the re-cap as you go, this way you know where problems are! and take your time, ripping up traces
will ruin your afternoon! N
Title: Re: Dim button stopped working properly
Post by: sintech on February 07, 2013, 01:10:49 AM
That made it easier. The part is 4069. I'm assuming this ic will do: http://www.amazon.com/NTE-NTE4069-4069-IC-CMOS/dp/B0002FRF06

Hi, I don't have a 24 card schematic in front of me, but thinking this must be the logic that drives the transistor that does the work. Defo worth a punt!
Title: Re: Dim button stopped working properly
Post by: Jermbob on February 14, 2013, 06:11:49 PM
I got the part to replace T4 on the 82e24 card today, and popped open the master section to put it in. Long story short, where the 82e24 card would be, is a 82e154 card. This seems to change things.

I should mention that I have a 6k.

Any advice on how to move forward?
Title: Re: Dim button stopped working properly
Post by: sintech on February 16, 2013, 12:05:49 AM
Hi, for the '154' card look in the direction of T19, that would be my first change.
Title: Re: Dim button stopped working properly
Post by: Jermbob on February 16, 2013, 05:36:12 PM
Success! I replaced t19, and it works great.

Thank you!
Title: Re: Dim button stopped working properly
Post by: sintech on February 16, 2013, 07:16:03 PM
Success! I replaced t19, and it works great.

Thank you!

Brilliant! T19 should've been the same part as T4 on the 4k card.

 
Title: Re: Dim button stopped working properly
Post by: Jermbob on June 13, 2013, 10:00:56 PM
The dim button went out again, and I replaced t19, thinking it would fix the problem, but it didn't.

Any thoughts?
Title: Re: Dim button stopped working properly
Post by: sintech on June 14, 2013, 09:38:45 AM
Looking at the drawings, this what is going on:

A switch (dim button) and a diode feed a voltage to T19 and T25.

T19 feeds a control voltage into two independent circuits:

R104 (left circuit) and R106 (right circuit) these two resistors operate the Jfets that punch the Dim pot into circuit. (dimming the sound)

T25 drives the dim lamp and penthouse "Dim" LED's (this is coupled to T19 in two places)


I'd change T25 (4093) just to rule that out, then it's extender time…