ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1]   Go Down

Author Topic: Strange Yamaha M7 problem or is it?  (Read 769 times)

Frank Czar

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 70
    • Website
Strange Yamaha M7 problem or is it?
« on: April 20, 2019, 09:38:44 am »

Hey Guys,

About a year ago I wrote in and asked for help with an M7 that would not boot up, it would attempt to yet never was able to complete the sequence. This problem had started slowly and I would have to turn it on a couple times for it to fire up but within a couple months (maybe a couple uses per week) It would take 10-20 tries for it to fire up.
I took it apart cleaned and re-seated all connections, changed the battery and still the same thing.
I put it on the back burner for about a year and was just getting around to sending it back to Yamaha for repair and why I don't know but I tried one last time, keep in mind I hadn't tried turning this on in over a year and this time it fires up perfectly, I have had it out for a week now testing it everyday now for a week and no problems, its been working perfect.
The only thing different in the equation is I have a different IEC cable for power, could the previous IEC cable been hanging on by a strand or two of copper and not giving it enough current to fire up? Any other possibility's?
Logged
Frank Czar
Concert Works
Daytona Beach FL. & US Virgin Islands
www.concertworksvi.com

Scott Helmke

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1531
Re: Strange Yamaha M7 problem or is it?
« Reply #1 on: April 20, 2019, 02:37:51 pm »

It took you this long to try a different cable?!?

To answer your question, no, I've not seen a problem specifically like that. Likely I would have put a meter on the PSU output during bootup to see if that was the problem, though.  Also you can disconnect most of the cards, such as inputs, outputs, and control surface, to see if one of them is screwing up the bus communications.
Logged

Frank Czar

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 70
    • Website
Re: Strange Yamaha M7 problem or is it?
« Reply #2 on: April 20, 2019, 09:23:54 pm »

It took you this long to try a different cable?!?

I have not been working on this for a year, after having no luck re-seating, cleaning, batt change, I put it back it its case with the intention of sending it back to Yamaha but things got busy and I just recently pulled it off the shelf to send it back for service.

When checking it out last year I never tried a new IEC cable because there was power to it, it would try to boot up but wouldn't.  The IEC cable is not something I would normally check being that it had power to it, screen was on, lights blinked, etc.

Ideas on why its working perfect now is my question and like I said the only thing different is the IEC cable
Logged
Frank Czar
Concert Works
Daytona Beach FL. & US Virgin Islands
www.concertworksvi.com

Jim McKeveny

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1089
Re: Strange Yamaha M7 problem or is it?
« Reply #3 on: April 21, 2019, 06:03:47 pm »

Is this an M7 48 or 32? I've seen oddball boot problems on 48's because channels 33-48 are fed by a 2nd power supply within console.
Logged

Scott Helmke

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1531
Re: Strange Yamaha M7 problem or is it?
« Reply #4 on: April 22, 2019, 12:58:48 pm »

Is this an M7 48 or 32? I've seen oddball boot problems on 48's because channels 33-48 are fed by a 2nd power supply within console.

What I've seen with the 48 channel mixers and PSU issues is that the power supply card in the 2nd bay (channels 9-16 and 25-32 on the surface) goes bad because it's feeding an extra input card - I've fixed at least couple where one of the analog rails on that card dies and those inputs (I think 17-32 plus STIN) get all distorted.

When I've boot issues in those consoles it's been because one of the various cards has started mucking up the communications bus.  Most recent one I fixed was caused one of the channel bank button & meter cards getting wet, to where even after it dried out there was still enough corrosion on it to cause problems. I found that one by just disconnecting all the channel bank cards and then reconnecting them until it stopped being able to boot.  In that one I was just able to clean off all the corrosion on the various chips to get it working again.
Logged

ProSoundWeb Community

Re: Strange Yamaha M7 problem or is it?
« Reply #4 on: April 22, 2019, 12:58:48 pm »


Pages: [1]   Go Up
 



Page created in 0.04 seconds with 23 queries.