(Almost) Dead Mac 550

[bakarmans]

hi all ,

also I have the same problem but #### make random flashing , & hear the beep sound in power supply board .

anyone can guessing ?

[Ashley R]

to drag up a older one

 

got a MAC 550 that was working beautifully only a week or two ago, and I just fired it up, and im getting **** flashing on the screen, and all 4 status LED's are also flashing.

 

THere is power to the fans, and they are spinning up correctly, but there is power to nothing else. There is also a beeping noise.

 

From what I've read above its something to do with the motherboard?

 

Cheers

[Ashley R]

and another little update, after pulling some more out of their cases, have got a 2nd one with the same problem.

[Just Some Bloke]

Take a look at the earlier post by Matt Cowles who used to be a service engineer with Martin (when they had such people in the UK - now they don't). I can assure you that if Matt says you need to re-install the software then that means that re-installing the software is what Martin themselves would do. Have a look at the manual to see how it is done.

[Ashley R]

software it is then!

 

any reasoning why they would lose their memory, or is this something that just happens now and then?

[Rekal]

I have 4x Martin mac550, all the same problem.

#### flashing 2 times/second and not booting.

 

I also hear clicks on the power supply (2x per second)

the click 1x per second is normal (it does when the lamp is off)

 

I once swapped the power supplies with heads that still work, and then they start up.

The cable between the motherboard and the power supply is also sometimes a problem, just loosen it, squeeze the sockets with pliers and put them back on.

in my case the power supply's are bad. with exactly the same symptoms.

unfortunately I don't have a schematic to fix them at component level.

Edited December 16, 2020 by Rekal

[Richard CSL]

Sounds like the pat test used high voltage spike to test earth leakage and has somehow wiped the software.

certainly try swopping power supply units over, and as others have said check the voltage of the power.

good luck, remember they are almost 15 years old now.

[Soosiologe]

I‘ve got two 550 as well. One was slowly blinking **** and the other one did so rather quickly and uncontrolled and ran the fans at full speed. I uploaded the software including the Bootloader to the first one and it worked just fine (using the Martin Companion Cable).

With the second one, I was convinced the power supply was failing. However, if you unplug the cable running from the display module to the Mainboard, the fans will power down and the head initializes perfectly. After that’s done, most of the time you can plug in that cable again and use the display and controls just fine (works like that for both heads since the second one refused starting up too). I suppose it has to do with the power supply’s 5V rail, which it also needs to power its feedback ICs.

The yellow Tantalum capacitors on the power supply definitely have been changed poorly by some previous owner, I’ll see if they’re still good or retouching the bad solder joints will suffice. According to the labels, they also use power supplies from 2002 and motherboards from 2003, so maybe they were part of the batch with the bad PSUs.

[Jivemaster]

Random comment, I've never opened a mover.

 

Do these rely on an onboard battery? Old computers sometimes had a NiCd battery soldered into the board, if it went flat the board couldn't boot and the boot memory could die, if it leaked the battery would eat the copper tracks and the board was probably useless.

 

If your mover has been in a case for many months a flat battery is highly likely.

 

Sometimes the battery is a lithium coin cell that can only be replaced.

[Soosiologe]

They do have a rechargeable Lithium button cell (CR something 20) which is spot welded onto a holder which is glued to the PCB, so it's a pain to swap that out but I reckon it holds a charge no longer than a few minutes.

If I got this right, that's why upon the first boot, the head flashes **** in a controlled manner with a constant brightness (in contrast to a PSU failure where frequency and color of the blinking are random). A red LED on the PCB indicates "FPGA load" and the firmware is loaded. After a minute or two, the head starts normally, that’s also what you would see when uploading a new Bootoader.

When re-starting the head within a few minutes, this does not occur - probably because the battery holds a charge for this short period of time.

Settings however are not affected as they seem to be written to the flash memory.

Edited December 18, 2020 by Soosiologe

[Jivemaster]

Motherboard batteries are either rechargeable or replaceable with some difficulty but failure to do one usually costs you a motherboard as the corrosive leakage will eat both board and copper.

 

If the mobo will not start up then a new battery and a reflash may be needed.