Two stubborn d8b's

[RJH_MUSIC]

I think the meanwell embedded switch mode powersupply smps 5vdc 30A 150W is a good replacement of tge Astec lps152. MEANWELL Model RSP-150-5RS. Check it out and let me know if this is a good replacement pls

At 1st glance you might be right but I'm concerned about one thing. 1st I should have done more research before I bought power supplies, As I think I bought all the wrong ones. Trying to sort out the plus in -16 V problem 1st and then I'll turn my attention to the 5 V supply. What concerns me is that the Aztec LPS 152 has 2 outputs, +5 and +5 sense. I am learning that only the more expensive models of the power supplies by meanwell actually have that output. I had purchased the meanwell model RS150 - 5 which may not have been sufficient but I can't tell yet because I still have the +/- 16v problem to solve. 1 I'm using a nice long weekend to work on the PSU unit and will post pictures later today of my progress. The other problem is if you follow the instructions it were originally posted in the forum, They will only work on the probox application not to d8b console as an audio mixer and that's why I need more powerful supplies. You just Helped me to solve a problem and a question that I that I had so thanks. Meanwell makes a switching power supply with +5 sense but it is rated at 30 amps amps which I originally thought was too much. If what you say is true this would be a good replacement. There are a couple more things I am considering. If none of these work well then what I might do is use the original linear power supply board from the D8b to generate to generate the +48, and +/-16 and use power supply you suggest to generate the +5 and +5 sense. But to do that, I need a suitable transformer to connect to the linear power supply board so that I don't have to use the original one from the d8b. I called electronics and they cannot find the part number because it's too old in their system I'm looking for some kind of specification sheet that lists the output voltages.

[RJH_MUSIC]

Hey Carlos;
Good to see you posting again, even if your having troubles!
You'll get it sorted.
Cheers
Bruce

Hey Bruce, yes this is the place to sort problems but also to say hello to good old friends. I think i have the PSU (probably the ASTEC LPS 152) failing. Although i cleaned all the d8b's ribbons im getting frozen meters after couple of minutes. The fault was isolated to one of my remote CPU units. The two d8b's do not fail when both are connected to same remote cpu. When i plug them to the other remote CPU i get weird things like meter bridge freezing or a dead console without sound signal. I have to change the PSU of this unit since i dont want to bank only on one. The one that is working is still an old unit.

Maybe someone can answer this for me:

IS the 5v Astec LPS152 responsible to feed good electrical supply for the clock? If yes so this means that the d8b's are failing (freezing meters) due to this power supply.

What is the 16v, 12v, 48v power used for in the d8b and from which power supply unit please?

I would appreciate if someone writes a guide on how to replace the PSU units with modern units.


Thanks a lot

Carlo

Check the post on power supply build but here you are

The d8b needs 6 voltages

+12 supplied by remote psu
+/-16, +48. Supplied by the transformer regulated by the Linear Power Supply Board
+5, and +5 sense from LPS 152 power supply connected the the linear power supply board.

All connections to the console are made using the BFC which has 18 wires all connected to the linear power supply board.

[RJH_MUSIC]

+48 is phantom power on mics,
+/-16 used in audio circuits.
+12 and +5 for lights, meters, pots, faders.

[Carlo]

Hi friends,

I have my d8b getting the following problems:

1. Stuck meter LED's with non operational surface including faders BUT sound works fine. The remote software works fine.

OR

2. Switches off the surface leds. Only the Fluorescent screen on the right is kept ON. BUT sound works fine. The remote software works fine.


Ribbon cable cleaning has been done. Im sure the problem is related to one of the power connectors from the power distribution board to the brainboard, Jack-field or card cage. But i cannot understand if the problem of the stuck LED's is related only to the power cable to the card cage or not since the if its a clock issue or loss of power to the clock i believe the d8b will freeze like i used to have.

Secondly, I think that the switching off of the surface leds is related to the brainboard power connector from the distribution board and not to the any other areas like the card cage or jackfield. In fact the ribbon cables are running from the brainboard to the 3 surface modules and also to the fader modules. So i think that the problem is loss of power from the distribution board to the brainboard.

Your help is greatly appreciated so that i trace this nuisance. I have no issues with my d8b's other than these freezing LEDs etc. I want to solve this once and for or before wasting money on another system which i dont want.

Is soldering in place instead of the power ribbon cables solves the problem once and for all?

Please help.

[Phil.c]

You've reseated/cleaned the connector which I seem to remember is tucked out of sight?

[Carlo]

The ribbon connector that runs from the distribution board to underneath the jackfield right? I think so but i will clean again. What is it responsible for?

[RJH_MUSIC]

I am betting on the LPS-152 power supply. Classic symptom - Power on a cold desk and everything works fine. About 5 - 10 minutes into running, Aztek power supply fails due to heat and everything goes haywire. Stuck Meters, LED lights either not functional or jumping all over the place. Faders unresponsive.

You might also have a faulty Linear Power Supply board. All of the power supplies as well as the transformer plug into to this board.

RJ

[Carlo]

The only problem is how to find a replacement. I though about recapping maybe it solves the problem.

[captainamerica]

I am betting on the LPS-152 power supply. Classic symptom - Power on a cold desk and everything works fine. About 5 - 10 minutes into running, Aztek power supply fails due to heat and everything goes haywire. Stuck Meters, LED lights either not functional or jumping all over the place. Faders unresponsive.

You might also have a faulty Linear Power Supply board. All of the power supplies as well as the transformer plug into to this board.

RJ

I would agree with RJH

[Jondav1120]

Hi Carlo,

The console hardware consists of two almost completely separate systems, the control surface and the dsp hardware. The only link between the two systems internally is a serial data link that is used to transfer the meter level data direct from the dsp to the control surface. Al other data is passed to and from the CPU over two bi-directional serial lines (the 25 pin data cable).

If the audio still works when the problem occurs then the dsp board is still functioning as it should. By the same token, if you can still control the audio using the faders on screen then the data link from the cpu to the dsp board is still functioning. This would tend to rule out the dsp board and its data link to the cpu.

It sounds as though the processor on the brain board is crashing, or ceasing to communicate with the CPU. If you have a spare data cable, I'd swap that out first.
A processor crash / reset can be caused by a power glitch on the 5v power supply, or data corruption. Try gently moving the wiring in the CPU in the area around the linear power supply and see if you can induce a crash. Same in the console, try moving the power ribbon cables around and see if you can crash it "on demand"!
Might be worth trying an OS reload, to eliminate the possibility of data corruption of the firmware files.

TBH, I agree with RJH and captain america, and my gut feeling is that this is 5v power related.

Best regards

John