My Transistors, original or copy?

[kees52]

Don't feel bad. A good technician never gets stuck on a tough problem, it's always the easy ones ... Years of observation.

I'm surprised that reverse connected capacitors caused that problem, not unless they do have voltage across them. I'm just glad you got it working.

-Chris

Tha caps are not normal elco,s but Tantalum capacitor these leak voltage when connected wrong. and the amp has a negatieve fantom supply for the mic a la mister linkwitz, modded panasonic.

regards

 

[anatech]

That will do it.

 

[Hdonly]

Just ordered these 2sk170bl's on ebay. Couldn't find them anywhere else. Guy in Israel on the bay since 2005. 100% pos. feedback. Who knows? Guess I will find out. Bought 2 matched,set of 4 X2sets.

 

[WalterW]

That's Alweit, they are good real ones.

 

[Hdonly]

That's Alweit, they are good real ones.

Thank you for that reply. That makes me feel much better. So hard to know what you get from ebay sometimes. I know I looked for a while and his appeared to be the most likely to be real.

 

[AndrewT]

Hd,
measure Idss for each and mark/label them, for future use.

 

[metallicus69]

That's Alweit, they are good real ones.

+1

Bought from him lots of times and always the real stuff.

 

[Hdonly]

Thanks all. Glad to know my parts will be the real. Will be building the Pass B1. Will measure all that I get. They are supposed to be in matched pairs.

 

[AndrewT]

Check them. But make sure the battery voltage does not decrease as you progress.

 

[Hdonly]

I plan on building a linear regulated power supply as I am also building a phono preamp. I would like one PS to feed my High Octane phono preamp and the B1. Was planning on two TL783 regulators as I need 48vdc and 18vdc.

 

[Preamp]

2SK389

2SK389. One is from the working channel of a Yamaha Power Amp, the other one was supposed to replace the faulty one of the other channel. Any thoughts? 😛

 

[AndrewT]

fake

test the other half as well.

 

[metallicus69]

2SK389. One is from the working channel of a Yamaha Power Amp, the other one was supposed to replace the faulty one of the other channel. Any thoughts? 😛

Fake! Exactly what I have got from aquawayindustrial , a relabelled NPN. I sent eBay the pictures with the screen of the DCA and won the case. Received a full refund.

 

[AndrewT]

Did you ask Ebay to bar/ban that faker from their site?

 

[Preamp]

The other half is an NPN, too.

I did not order my part off eBay, but from ASWO. They once sent me fake Panasonic FC's, too. I called them up, but unfortunately they were'nt able to replicate my measurement. At least they brought two new parts on the way to me, so I hope they are genuine this time. They also told me they didn't have any such problems lately, so it's good to see that I'm not the first one to discover bipolars in disguise as JFETs.

 

[AndrewT]

We had a group buy years back.
The purchaser distributed the items around the world to us Members, without checking what he had bought for the Group Buy.

It cost him a lot of money, since I don't think he got a full refund for the dual BJTs that had been relabeled.

 

[ivoa]

Hello all,

here are the pictures of MJ15004G. Can you please tell me your opinion, is it original or fake? You can see that wire connecting base is thinner than wire connecting emitter.

Ivo

 

[zsjkuki]

Hello
It is not fake.
It is original ON semiconductor.

 

[K-amps]

Looks fishy... Die is small... More like 100w-150w trannie, not 250 watter.

 

[ivoa]

Does anyone has picture of opened geniune MJ15004G?