Removing Cards From a 388

Its actually much better to leave the dress panel intact with the cards still nutted to the dress panel, and instead start the removal by removing the bottom panel, *carefully* removing the buss PCB that runs across the bottom of all the channel cards, and then remove the other connections and pot nuts and finally each cards. If you try to pull them from the top you risk damaging the buss PCB and/or connections.

Outside of that, can you be a little more specific about what do's and don'ts you are wondering about? It might help if you share a little about to what extent you are going to clean/inspect...how deep your dismantling is going to go...it might help you get more relevant answers.
 
Well... I'd like to not got shocked.

I'd like to clean the inside of the machine and reseat the monitor cards. They've developed a fault which apparently is quite common and is down to a cold solder joint. Basically the monitor section no longer produces a stereo (left, centre, right) signal but instead only a mono signal that cancels out when the pan knob of a monitor control pair is centred.
 
As far as electrical shock hazard its no different than any other electronic device...make sure it is unplugged from mains power. There is typically some charge that remains in the power supply filter caps, but that should drain pretty quickly.

The monitor amplifier PCB isn't a plug-in PCB, so you can't re-seat it like the PCBs in the upper cardbay. You *can*, however, re-seat the *connections* to the PCB. Tip the machine on its side and remove the bottom cover to access most of the connections, including the buss PCB that spans across the bottom of all the mixing section PCBs. Any connections you can't readily get to (if any...can't recall off the top of my head) may require removing adjacent PCBs, or partial removal of the monitor PCB itself (remove the buss PCB, all connections you can access, remove the pot nuts and any screws fastening the PCB to the dress panel, and slip it down as far as it can go to hopefully access any remaining connections).
 
Okay, it looks like the only way I'm getting the mixer section faceplate back on is to remove all the channel cards from the PCB they're connected to, screw them back on to the face plate and then clip the PCB back on.

Man, I wish we (a) still had techs who knew how to fix analogue gear in the UK and (b) I had the money to pay to get this done.
 
Before I go any further, which fader is the even buss one? The one attached to the red clip or the one attached to the white?IMGP2372.JPG
 
Okay, it looks like the only way I'm getting the mixer section faceplate back on is to remove all the channel cards from the PCB they're connected to, screw them back on to the face plate and then clip the PCB back on.

Man, I wish we (a) still had techs who knew how to fix analogue gear in the UK and (b) I had the money to pay to get this done.

Are you saying you can't get the dress panel back on because the channel PCBs have shifted around and you can't get the pot shafts through the holes in the dress panel?
 
Before I go any further, which fader is the even buss one? The one attached to the red clip or the one attached to the white?View attachment 105898

Per your picture, the buss fader with the white connector is on the left, and the one with the red connector is on the right, correct? So isn't the "ODD" buss master fader on the left = white connector, and the "EVEN" buss master fader on the right = red connector? I'm just following the wires from the connector to the fader as pictured.
 
Sorry, the faders aren't currently attached to anything. Can you remember which way round they should be from when you had yours? I don't want to have them back to front.
 

So, yeah. That's why I was saying if you want to remove the channel and master PCBs it is best to remove them from the bottom.

1. remove the bottom cover panel of the 388
2. carefully remove the buss PCB that spans across the bottom of all the channel and master section PCBs
3. Remove individual connections from the channel and master section PCBs
4. remove the pot knobs and fader knobs, pot nuts and any other screws fastening the channel and master section PCBs to the dress panel
5. remove the channel and master section PCBs from the dress panel
 
Yes they are.

I tried to figure it out from a photo in your thread, but a top down 2 dimensional image is pretty useless in this case. Especially with that snakes nest of wiring/
 
Hopefully you're taking lots of pictures before taking things apart so you have something to reference when it comes time to put it back together.

I'll have to look in the service manual for which fader goes where.
 
Yep.

I don't have access to my copy right now, and the freebie online is too poor quality to read the information necessary to answer your question. You have to look at the schematic for that PCB (BUSS A PCB? BUSS B PCB), and then find the buss master faders on the schematic and see which connector number each one is connected to. I think the schematic might even label the colors of the connectors, but I don't trust the 388 manual because of the number of errors in it, so I reference the connector number which is also printed on the PCB.
 
You tell me. The PCBs are printed with the name of the PCB on them. I do not have my copy of the service manual available at the moment.
 
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