OK Hive! ID this transistor?

The missus bought a guitar pedal on reverb. It arrived non functional. The seller said it worked fine when he shipped it and to go through the manufacturer for free warranty repair. Noisemaker Effects will not respond to emails or FB messages and their FB page is full of references to them being scam artists. great...

So I put on my "I build my own guitar amps and megasquirts" trousers and pop the back panel off and immediately see an exploded transistor on the delay/reverb board (the non functional portion of the pedal. No bits of the transistor are rattling around in the case meaning someone else has opened it up before i did. Also that 100uf electrolytic cap is bulged on top.

Sadly the face of the damaged part that contains the info I seek is missing

What I do have isn't enough to cross reference.

It is a Noisemaker effects "loveless" pedal. Fuzz and delay in the same box. I can't find a schematic anywhere. Delay circuits based on the PT2399 that I can find do not have this. Voltage stabilizer? buffer transistor? I don't know.

Just trying to recoup some of this wasted purchase. You guys know everything, right?

Can you draw up the circuit?

Then I would post it on DIYAudioProjects.com and wait until 'SunCalc' or 'gofar99' replies with an answer.

Well, it's either PNP or NPN!

Transistors usually don't just explode.  Something else probably failed and took it out. 

I think you need either a schematic or a really smart electronics tech who can "figure out" the circuit. 

You could replace it with a random transistor and see what happens.  They all do pretty much the same thing.

This advice is worth exactly what you paid for it. 

The PT2399 chip that's adjacent to it runs on 5v. I bet that's a simple 7805 5v regulator. I assume the effects pedal runs on 9v like most do? So the 7805 would be to step it from 9v to 5v to run the PT2399 echo/delay processor.

Side note, that thing looks home made. Not like low-volume niche manufacturer home made, but like one dude in a basement home made. The perf board is something I'm used to prototypes being made out of, not actual products for sale.

Also, if your missus bought this recently she should be able to return it. Repairing it might not be hard, given the construction style, but it's more difficult than it should be. Did she buy it on eBay? They have very good buyer protection. If not, did she pay with PayPal? Same deal. It's hard to be a seller on the other end of a buyer complaint with either of those, but as a buyer you can be pretty sure you'll get your money back in this situation. That is, assuming you don't want to go ahead and repair it.

1988RedT2 said:

Transistors usually don't just explode.  Something else probably failed and took it out.

 

I meant to say something along these lines, too; it's possible replacing this and the capacitor will fix it, but it's also possible they've stressed that little TO92 cased 7805 too much and you'll have it pop again on you later. The failing cap might have stressed it, too - who knows. The pt2399 only draws 30mA max so it's not stressing the 7805 which is rated at 250ma in that case. But if anything else draws current off it you'd have to add up the total current load.

It was purchased on reverb.com

Seller says it was fine when shipped. I assume there are a lot of issues with people trying to return "defective" effects they just didn't care for.  I might escalate it but if I can replace a few pieces and eschew that I will. 

My guess is someone plugged it into the 18v portion of their pedal board power supply.  It isn't labeled for voltage. 

And yes. A dude in his garage builds these in small batches.

Let me know if my ID of the transistor turns out right. I need a win every now and then. ;-) This might help you chase out the function:

Taken from here:

https://www.electrosmash.com/pt2399-analysis

which is a great in depth look at that chip and should be all you need to figure out how that board works. I think the delay on the loveless pedal is a basic implementation of the pt2399 chip. I could be wrong.

I think Mr. Culberson is on the right track.

In the pedals I’ve built, I haven’t seen that letter designation on a transistor.  2N, BC, and others, but not an L.

Soldering in a SIP socket would make it easier to replace if you don’t get the right replacement on the first try.

I think the easiest way to be sure is to see if one of the pins of the transistor goes to pin1 on the pt2399, which would pretty much mean it has to be a regulator.

In reply to Jumper K Balls :

If the dude builds them in low volume in his garage surely the easy button here is to contact him and find out exactly what part he uses? 

In reply to daeman :

Sounds from the initial post like the easy button's also defective. No responses to email/FB.

I’m not a forensic electronicsist, but I suspect the damage in the pic may be physical rather than an electronic failure.

From personal experience if you aren’t careful bending the legs, you can break them right out of the package.  Maybe it cracked during installation, worked for the test but didn’t survive shipping?

In reply to Ransom :

I read should learn to coffee before internetting

Edit: I should also learn not to use emoji's, the seem to royally screw up my replies!

I read it as the seller wouldn't respond, reading compression fail!

Does the maker respond ever, to anyone? Makeing pedals could be a side gig, meaning he doesn't have alot of free time to chase up issues with people.... Or he could just be a douchebag....

Might be worth leaving a message on their FB page asking if anyone would be willing to open their unit to help get a positive ID on the damaged component/s

dculberson said:

I think the easiest way to be sure is to see if one of the pins of the transistor goes to pin1 on the pt2399, which would pretty much mean it has to be a regulator.

It indeed does!