TC Electronic problems...
- Thread starter drpat
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Help Support GroupDIY Audio Forum:
MidnightArrakis
Well-known member
That looks like an "OrCAD" schematic from 1996!!! If you happen to have access to that OrCAD schematic CAD-file, I could import that into my current CADENCE/OrCAD "PCB Editor" program and then I could spruce it up a bit!!!
Just sayin'.....
/
That's straight from TC Electronic's service documentation server, no original CAD files to be seen / found.
JohnX
Well-known member
Thank you for this.
The fuse is OK.
I am not highly skilled when it comes to diagnostics/troubleshooting so I am trying things one at a time.
I had a few brand new capacitors here and I taught myself how to measure the capacitance of them with my meter.
All of the new ones seemed to spec out pretty close to what they were labeled as. The large capacitor at C5 gives me different readings every time I touch the terminals to it. It never gives a reading close to what it should be, which is 47uF. Most of its readings have been very low decimal place values between 1.9 & .0x.
So far it’s the only one that has been behaving that way, but I’m not sure if that means there’s something wrong with the capacitor or if there is something wrong with my testing approach.
JohnX
Well-known member
MidnightArrakis
Well-known member
"Live & Learn".....huh???
C5 will getcha every time!!!
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s2udio
Well-known member
How about the upc/uuc (variations) pwm chip on the riser board ! 
Replace all small "heated" caps and check every current/ MOxide drop resistors as well as the FET.
Seepost 37
Replace all small "heated" caps and check every current/ MOxide drop resistors as well as the FET.
Seepost 37
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JohnX
Well-known member
I wouldn’t even know where to look for that. So far, the only things that I have been attempting are suggestions that have extreme clarity within their instructions.How about the upc/uuc (variations) pwm chip on the riser board !
My level of expertise is so low that my DIY experience has been building direct boxes & transformer color boxes, and specifically NOT troubleshooting dead power supplies - in other words, I barely know what I’m doing and this is beginning to feel a wee bit out of my jurisdiction.
Obviously, the C5 replacement was ineffective.
I am sure I don’t have the time or the patience to replace every single component one at a time And that may not even necessarily solve my problem.
I suspect that this particular project may be better left in the hands of someone who actually knows what they’re doing. If I continue, it’s going to end up back in a box in my garage which is where it has been for the last 15 years.
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pucho812
Well-known member
If I may interject again.
As you live in Los Angeles, when it comes to digital gear I highly recommend ADS. Audio design and service is in burbank. Talk with norick. I think that is how you spell his name. Anyway they are great. Back in the day, they used to sell me Alesis parts as they were an authorized repair center for them.
They are good people and are quick to fix items.
They are my goto on digital and overflow although I haven’t had overflow in a long while
JohnX
Well-known member
C5 replacement didn’t work, either.
I
Thanks.
I spoke to him on the phone yesterday.
He politely opted out.
I am secretly hoping someone in this group might be interested in taking this on.
pucho812
Well-known member
I haven't been following along closely but what unit is it? and what seems to be the issue exactly?
JohnX
Well-known member
TC Electronics Fireworx - circa mid 2000’s
Doesn’t power up anymore, so I had hoped that following some of the instructions in this thread would revive it, but in this case it needs a little bit more more TLC and far more than I probably know how to give.
Replacement power supplies are no longer available.
So far, I have replaced two capacitors at C5 and C7 and checked the fuse.
pucho812
Well-known member
Can you confirm that the psu is indeed faulty? A unit not powering on while it points to a psu fault maybe be related to something else.
JohnX
Well-known member
That certainly sounds like it’s way out of my jurisdiction.
Just to be clear, I am an extreme noob
pucho812
Well-known member
I understand. I can take a look but unlike analog gear I couldn't promise anything
I have not read through this entire thread but will add a few notes, having fixed a number of these supplies back in the 00's.
1) Like many SMPS these units will fail because an electrolytic cap in the front end of the circuit goes high ESR. So, measuring for capacitance without measuring ESR will not rule out that cap as I have seen them still measure close to their marked value, but with high ESR.
2) You can't use just any cap with the same marked value. You MUST use a low ESR cap like Panasonic FM or FR series, or Nichicon equivalent (HE, I think).
3) This is not a job for a noob, there is some serious high voltage present in these supplies.
1) Like many SMPS these units will fail because an electrolytic cap in the front end of the circuit goes high ESR. So, measuring for capacitance without measuring ESR will not rule out that cap as I have seen them still measure close to their marked value, but with high ESR.
2) You can't use just any cap with the same marked value. You MUST use a low ESR cap like Panasonic FM or FR series, or Nichicon equivalent (HE, I think).
3) This is not a job for a noob, there is some serious high voltage present in these supplies.
JohnX
Well-known member
We definitely got that covered based on the initial Svart posts, but it had no impact.
(Panasonic Low ESR 105C)
Well, occasionally one of these supplies was just...dead. I may still have a few of these kicking around...I can check next week. If I revive one, I'll let you know.
