diyAudio

diyAudio (http://www.diyaudio.com/forums/)
-   PA Systems (http://www.diyaudio.com/forums/pa-systems/)
-   -   Konzert Amp & Speakers Website (http://www.diyaudio.com/forums/pa-systems/74642-konzert-amp-speakers-website.html)

clem_o 27th September 2006 01:39 AM

Re: k series amp trannies
 
Quote:

Originally posted by audiomachines

5.Driver transistor 2SC5200 and 2SA1943
6.Output Transistors 2SC5200 and 2SA1943


Any idea if the transistors are "real" toshibas or fakes?

Cheers!

AJT 27th September 2006 01:59 AM

Quote:

Originally posted by audiomachines
hello,

I got some CrestAudio schemes Vs, CA, Pro Series etc.
If some of you decided to clone one sali ako.:D

Best Regards,
audiomachines

there is a guy here named ferdz, and also at pinoydvd, who is at 24 very well versed with protel pcb design software, i believe it won't be hard to convince him to design the pcb for us should there be enough interest on it.

AJT 27th September 2006 02:00 AM

Re: Re: k series amp trannies
 
Quote:

Originally posted by clem_o



Any idea if the transistors are "real" toshibas or fakes?

Cheers!

unlless you get them from the factory, it would be very hard to tell...


:bawling:

clem_o 27th September 2006 02:09 AM

Hi Tony,

The Base to Emitter junction capacitance appears to be a good indicator of 'authenticity'. The real ones have a higher BE capacitance, due to larger die size.... usually a few nF. Specifics for the 2SC5200 etc I don't have however...

Thread is here:

http://www.diyaudio.com/forums/showt...threadid=82638

Also, I guess if the transistors keep blowing up then its a good indication that they are fake... hehehehe!

Cheers

Clem

AJT 27th September 2006 02:16 AM

Quote:

Also, I guess if the transistors keep blowing up then its a good indication that they are fake... hehehehe!
yes, but i would'nt be too quick to call that, you can easily fry genuine transistors if the biasing is not right. i've learned that repairing Sansui amps....Sansunog is how we called those amps from the late 80' to early 90's....:D

clem_o 27th September 2006 02:35 AM

Haha, nice name.

Re frying up transistors - true, however if the bias is set right and isn't drifting YET the thing transistors keep blowing.. We had an Onkyo amplifier with those particular symptoms. Came in with blown outputs, bought a set of trannies from Raon, put them in, check bias. Everything ok, even powering speakers for a while. Once you push the amp to high power levels, poof... Happened several times, and that's actually what started us guessing that we had fakes!

Cheers!

AJT 27th September 2006 02:42 AM

yes, that would be an unmistakeable analysis....:D that is why i prefer to buy those junked boards with parts, than buy new trannies from say, DEECO... oriental, newport and liamco seem to be reliable though...

clem_o 27th September 2006 02:45 AM

Hi Tony,

Hey, that's a great tip! Gracias!!

Clem

MGR 27th September 2006 04:39 AM

Original toshiba transistors can be bought at DECIBEZ (Ronquillo St.)The A1943 and C5200 is priced at 150 each.You can buy cheaper transistors in RAON but it depends on their stock sometimes good more often fakes.

clem_o 27th September 2006 04:51 AM

Hi MGR,

That's a bargain if those are real!!

I'm waiting for anatech if he can give me some capacitance readings on known original devices. When I have that info I'll bring a capacitance meter to Raon and check these out!

Cheers!


All times are GMT. The time now is 11:50 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio


Content Relevant URLs by vBSEO 3.3.2