Maybe need a different power supply...

sweetbeats

sweetbeats

Reel deep thoughts...
Hey, folks...

So I’ve been doing a lot of work on my Tascam prototype console, the “M-__” the past few weeks...lotsa different stuff I’ve got in the cooker right now. But one of the major facets is continued power supply testing and modification. It’s looking like I may need to do something different than continue to modify the PS-520 power supply I’ve been using from an M-520...I think I’m about to the limit of the +/-15V supply. You all know I’m into the aesthetics...I like the fact the PS-520 supply is from a model derived from my prototype...keeps things in the family line...but I really need a supply with +/-15V rail’s rated to 3A and I think the PS-520 is starting to approach limits around 2A...that’s plenty for the M-520, but not for the M-__. Does anybody have a Tascam console supply for sale from a larger console than the M-520 (like M-3500/M-3700), or does anybody have ideas for good rack-mount solutions? Ultimately I need something with +/-15V (3A or better), +6V, +48V, and +/-35V (1A or better). I know that last set of rails will not be turn-key...I’ll have to modify an existing multi-rail supply...

The Acopian stuff looks interesting but I’m overwhelmed by all the models of modules and how they mount. Power One modules are a possibility but same issue with mounting.

Thoughts?
 
I have two M3500 Power Supplies.
I bought the second one several years back when I spotted it on eBay...thought it would be smart to have a backup for the M3500.
Of course now...I have the M3500, the PS units, and all kinds of extra parts...and I'm trying to unload it all since getting the Trident.

That spare PS I recall only powering up once, with the console connected to it to see if it worked, and then I went back to using my original one. I seem to think that the spare may have actually been rebuilt/recapped (???) because I opened it up to check it out inside...but don't hold me to that.

So...you need/want it...?...it's yours.
I can part with one PS and still have one for the console, in case I can find someone who wants to buy the damn thing. :facepalm:

PM me your shipping address.
I'll get it boxed up over the weekend and FedEx it to you on Tuesday.

AFA the Acopian stuff...yeah, I was also overwhelmed by all their models and how one goes about getting the right thing.
Thankfully...the 4 Acopian power supplies that came with the Trident where all sussed out by the previous owner's technician...and he knew what he was doing with the whole power distribution upgrade he did on the console...so I didn't have to try and figure out which ones would be the right ones to buy, and how best to integrate them. :D
 
Oh no way...for real??

:eek::o:D

Before you do that awesomeness let me verify the transformer is up to the task...I’m pretty sure it is. Just had time for a peek at the schematics but so far the input channels alone on an M-3500-32 have a maximum theoretical power supply demand of 1.44A...five NJM4580 dual opamps between the Input A and Input B PCBs...so that’s a really good start.

There’s no +6V supply but there IS a +8V supply and I believe it uses a 7808 regulator and I could just swap in a 7806 and be on my way there...

This has potential...

The power supply umbilical to the console uses a DSUB connector?

Huge thanks for the offer, Miro!!!
 
sweetbeats said:
The power supply umbilical to the console uses a DSUB connector?

Huge thanks for the offer, Miro!!!
Click to expand...



Not my PS pictures...but this is the type of connector:

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Let me know if it will work for you....so I can find a box for it. :)
No...I don't have a second/spare umbilical, just the one that came with the console...sorry.
 
Daaaaaang on the umbilical though that would be too good to be true. That’s a Hirose connector...Sumicon 1600 series...same as they used on the M-520 supply...and on all the interconnects on a number of their tape machines like the 85-16, MS-16, ATR-60 series...I’ve got extra parts for the PS-520 but that’s a 20-pin connector and the PS-3500 uses a 28-pin connector. The Hirose stuff is unobtanium for years now.

Begin the search, I will.

444808E9-50FF-4750-B749-DFDC49230C6B.jpeg

P.S. still need to finish guesstimating the load capability of the +/-15V supply in there.
 
Yeah...I know these connectors have been MIA for years now.

It might be possible to replace it with something more common...but probably a good bit of work, first finding something that would fit in the same general slot, and then a way to get it attached to the unit.
Probably the simplest solution would be to remove the original, splice in a pigtail, and then just attach to the pigtail a more common plug, one that would marry-up with your board....let it just hang, rather than trying to hard-mount it to the PS.

Just let me know if you want it.
 
Could you get away with 25 pins on the ubiquitous and cheap as chips D-Sub connector? The contact rating is 5amps.

There is apparently a 37 pin DS but not common out of hospitals!

Dave.
 
My BR-20T uses a 37-pin DSUB for the remote/sync interconnext. :D

Yeah, could probably make DSUB work, but I’m holding out to see if I can get a rectangular mil-spec Winchester connector to work...have spares here from Ampex stuff and would far exceed the Hirose or a DSUB connector.
 
Okay...I’m sure I can make this work. The factory Hirose connector hood is about 3/4” thick. The pocket in the back of the PS-3500 supply would have to be bigger than that. I have spares of Winchester rectangular mil-spec connectors. Military-grade gold-plated connectors with all metal hoods, metal jack-screws, etc. The hood on this 24-pin connector is around 5/8” thick. I can make this work. Sweet.

51D6355E-42F7-440E-B72B-85D21C67909B.jpeg
 
Lol!

Yeah...all the old Ampex stuff uses massive Cannon and Winchester mil-spec connectors...they’re awesome.
 
Here's something to wet your appetite.

3500 PS Guts

You can right-click and download it.

So I opened up both power supplies, and TBH, even thought the spare I'm sending you has some labels on the outside that say "RECONDITIONED"....I don't think anything was ever touched. The place I got just probably put the labels on to make it look more appealing. :D

The guts between the two are identical...almost every single component I looked at...so I think it's 100% stock. Mine was still kicking strong until a year ago...and I know the spare powered up fine when I first got it.
Just don't know if having it sit around for several years without any juice flowing through it had any kind of negative effect on it...?...otherwise, it sat in my studio, so it wasn't like outside in the shed or anything.

I'll scan the PS schematic and PCB diagram for you and stick them in the box.
 
That's awesome...Thanks, Miro!! :D:D:D

That looks super clean in there!

Plenty of room inside there...looks like there are unpopulated rails on the PCB...wonder if this is the same chassis and board used for the MSR-24 power supply. Anyway, It looks awesomely perfect. I'll need to add a transformer for the +/-35V rails, but there's lots of room toward the front of the main transformer already onboard...the transformer I'm looking at is about 3" square.

And no worries on whether or not it is working 100% when it gets here...I'll likely be upgrading some components, recapping, and doing some minor mods to supply rails that will be staying, and then I'll be removing the +/-12V rails and replacing that stuff with the +/-35V stuff...and then of course incorporating the different output connector.

Can't thank you enough.
 
Ooo! Any chance you could post an attachment of that schematic M'?

I have a collection of such data and in any case, I think information on old gear should be in the public domain. Not current gear so much, don't want to make things any easier for illegitimates like Behringer!


Dave.
 
Yeah...no problem.
I might as well scan all the schematics for the M3500...only about a dozen pages.
 
The PSU for the M3700 uses the same PCB, but it's fully populated, and has a beefier transformer. I'm not sure I can say mine is quite as tidy inside as Miro though :)
 
The 3500 PS weights almost 30 lbs.
I'm sure the extra rails on the 3700 PS are for the automation...I would guess in the 5V range.

I got the PS boxed up and FedEx will be picking it up this afternoon...so you should see it on Thursday.
I printed the schematics out in in large format for you, and that's in the box. I'll also post the scans I did of all the schematics later today.
 
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