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15v data

15v data

2014-12-11 by martinjboisvert@...

Greetings to all,

 

Has anyone ever taken the time to write down how much current each board is drawing (on the + and – 15V rail) in a healthy cs80?  Or how much overall current one should expect (again on 15v)?

 

If anyone could also tell me what the resistance should be from the molex, it would help me tremendously!!!


Thanks


Re: 15v data

2014-12-11 by tconno@...

Hi, yeah the 15's are generally approx 70 Ohms to gnd.

Re: 15v data

2014-12-12 by martinjboisvert@...

Thank you very much,

That is what I am getting as well... Now I need to find the component that is making the PSU trip!  All 15V related boards are disconnected and have been tested individually and not one seems more suspect than the other!!!

Again if anyone has data on the power consumption for individual boards or for the the over all unit...  At this point any suggestion is welcome!!!

Cheers

Re: 5v data / been semi-offline with analog life :)

2014-12-12 by David Rogoff


On Dec 11, 2014, at 2:56 PM, martinjboisvert@... [yamahacs80] <yamahacs80@yahoogroups.com> wrote:

Has anyone ever taken the time to write down how much current each board is drawing (on the + and – 15V rail) in a healthy cs80?  Or how much overall current one should expect (again on 15v)?

 If anyone could also tell me what the resistance should be from the molex, it would help me tremendously!!!


Hi Martin & all!

Couple of notes from your forum manager here.  First, I’ll try and take some measurements in a couple of weeks for this.

Second, I’ve been in massive crazy mode for the last few months but hope to have something resembling a life very soon.  I was laid off a few months back and soon discovered there were no jobs for my work (ASIC design and verification) within commuting distance of my house.  My wife and I were thinking of downsizing our house a bit anyway so we went into a whole process of simultaneously 
Fixing up our house (about 10 years deferred maintenance and me putting holes in walls)
Getting an agent and setting up to sell house
Me taking some short technical classes in San José 
Me signing up and starting an online extension program through UCI (Univ California Irvine)
Me dealing with EDD (California unemployment office)
Me taking many professional development and job search programs
Me spending hundreds of hours updating résumé and looking for jobs (in Southern California!!!)
Wife and I searching for new place to live near potential jobs and still commuting range to OC for family and wife’s choir.
Looking at many new houses in Northern San Diego county and spending untold hours analyzing commute times and nearby shopping and dozens of other parameters.
Me having some surgery (after lots of time looking into health insurance - which I have to pay all of now)

Finally, about 8 weeks ago, in a matter of a couple of days, we sold our old house, bought a new house, and I got a job!  All great news but the last few weeks has been total insanity of packing, moving, unpacking, fixing stuff, working and learning new job, learning to hate traffic on new freeways, my Macbook Pro dying (eventually fixed for free - thank you American Express extra year warranty coverage!!!), and going nuts with the last few weeks of the two online classes I was taking and weeks behind on (one done 2 days ago and other have project and final this weekend).

Just a little going on so I haven’t done much in the CS80 world.  I have one I need to finish a house call on in the Hollywood hills.  Got it figured out and partly fixed on first visit but I didn’t have any $0.05 diodes with me!!!   Other is massive overhaul and mod-additions that’s been at my house(s) for way too long but luckily very reasonable owner has been about as slammed as I’ve been so hasn’t been bad about the delays - and he has lots of other synths :)

Anyway, classes done this weekend (and only taking one class next quarter - starting mid January) and have two weeks off at end of the month (unfortunately, unpaid since I’m a contractor right now…).  I plan to spend the two weeks sleeping a lot and finishing the unpacking which will clear out the area in my garage that will be my new synth workshop.  So, barring unforeseen circumstances (hard to type that without breaking out into laughter) I’ll be back on synth stuff by New Year!

Sorry - that went on a bit long so I’ll stop now.

 David  (now in Vista, CA - even further away from most of the synth owners up in L.A.)

Re: [yamahacs80] Re: 15v data

2014-12-12 by Tim Conniff

don't forget you could possibly have a failing supply under load ONLY, so it will fool you at first. Try loading the supply itself (no baords connected) with
the same load measurements as you are getting now, and if the supply fails, your boards aren't causing it per se. The design doesn't have the normal type voltage regulators which are notorious for having "foldback", but they CAN fail in a similar way..... at least for a while....eventually that changes to a full out failure, which is when it gets easy to figure out the problem. 
Although this would explain your having difficulty finding a bad board,
you could still have an impedance issue on the other lines. However, applying a bit of logic, you should be able to see
that just a few thousand ohms on each of the other output voltages,
would produce a "sane" level of current draw, and the supply should NOT fail under those conditions, thus pointing more definitely to the supply itself. Good luck
Tim



On Thursday, December 11, 2014 5:14 PM, "martinjboisvert@... [yamahacs80]" <yamahacs80@yahoogroups.com> wrote:


 
Thank you very much,

That is what I am getting as well... Now I need to find the component that is making the PSU trip!  All 15V related boards are disconnected and have been tested individually and not one seems more suspect than the other!!!

Again if anyone has data on the power consumption for individual boards or for the the over all unit...  At this point any suggestion is welcome!!!

Cheers