Cross referencing-finding parts

[Valvehead]

Once in a while i have a hard time finding output amp chips for guitar/bass amps. Are there any good sites to cross ref the part numbers ?

For example i need a Toshiba C5196 and a A1939 , cant find them anywhere.

[guitaraddict]

Maybe try nteinc.com. Not sure if it will help but it gives a new # and you can see specs on a pdf. I'm kinda new round here so if I'm way off base --sorry

[oc disorder]

Did you mean transistors? or output stages in one package?
I'm presuming transistors and I don't think Americans have the exclusive right to be confused !

http://www.smeter.net/daily-facts/11/fact4.php

"Japanese semiconductor part numbering tends to confuse Americans, both because numbering conventions are different in the two countries and because Japanese part numbers often are abbreviated. Some Japanese transistors have part numbers that begin with 2N and are equivalent to U.S. parts with the same numbers, but most begin with 2SA, 2SB, 2SC or 2SD. Semiconductors with part numbers that begin with 2SA or 2SB are PNP transistors. Those that begin with 2SC or 2SD are NPN transistors. However, the first two characters often are omitted to save space when printing on transistors, so a part marked C945 is actually a 2SC945. Japanese transistor part numbers that begin with the digit 3 are FET's. ©2004 Tigertek, Inc. All rights reserved."

Usually I look up the data sheet check the Collector emitter voltage and the current and HFE and find something in the same package.
eg Toshiba C5196 = 2SC5196
A1939 = 2SA1939 which is the PNP complement to the above
The Tip series is usually a good general replacement if you cant find the original.
If the voltage and current are slightly higher doesn't matter but unless the originals are overkill don't choose below those specs.
A transistor equivalent book is a good investment like Towers etc.
The examples below probably not ideal but will give you a rough idea.

[Steve Conner]

Indeed, if you see any part number beginning with A, B, C, D, J, K, then it's a Japanese transistor, and you should add "2S" when searching for the part code.

A, B, C, D are regular transistors, J and K are MOSFETs.

TIPxxx can sometimes be Darlingtons.

You could probably replace most TO-3P power amp transistors with more modern types like the 2sc5200/2sa1943, or MJ15024/MJ15025 for metal TO-3 packages. But if they're Darlingtons it's best to try and get the exact part.

The old Hitachi audio MOSFETs (2SJ50/2SK135 etc) aren't made any more, but Magnatec and Exicon make equivalents.

[jrfrond]

I keep the Japanese JEDEC Transistor Substitution and Specifications Guides handy for quick-and-dirty cross-referencing transistors, but I also make use of the online NTE guide. Usually, I will buckle-down and just do hard-core cross-referencing of specs, because on a lot of old semiconductor numbers just aren't available anymore. In addition, unless I am backed into a corner, I will not purchase overpriced NTE subs, unless it's a quick, one-shot deal.

[Enzo]

I am evangelical about not using NTE. Aside from the incredibly high cost - typically 4 to 10 times the cost of a real part - they are not exact replacements. This doesn;t matter much in a lone part, but in a power amp where the part must share current, it is critical the parts all be the same. Your shiny NTE replacement part won;t be.

[Valvehead]

Thanks guys

[Gtr_tech]

I am evangelical about not using NTE. Aside from the incredibly high cost - typically 4 to 10 times the cost of a real part - they are not exact replacements. This doesn;t matter much in a lone part, but in a power amp where the part must share current, it is critical the parts all be the same. Your shiny NTE replacement part won;t be.

I'm the same way. Plus they're not immune to the problem with all the fakes going around. Years back I tried using some NTE cross TO-3p parts to repair a simple 1 pair per side amp. I'm sure they were fakes 'cause they didn't last 10 min in the circuit. Drivers and bias string was good and no signs of oscillations. They just up and smoked......

I had better luck with SK subs....but they weren't cheap even at dealer cost.

[Enzo]

The only thing they had going for them is they sold them locally in TV repair part supply stores. But if I have to order something, I might as well just order the real parts in the first place.

Mouser sells NTE, and it is so telling when you are looking for some transistor and the Mouser search comes up with a list of various $4 parts and the NTE cross will also be on the list at $14.

I just looked, Mouser has the TDA7293 for $5.21 each, and the NTE version for $14.94.

$5.21 ($4.90 in 10 lot) is pretty low compared to lately. I may restock now that I see that.

[jrfrond]

All NTE does with transistors, like SK and ECG before them, is do the cross-referencing for you for a close sub, and you pick up the tab. Great for a one-shot deal or for "B" and "C"-grade techs who can't cross-ref specs. For quantity purchasing, it's a losing proposition. There are a few occasions when all you can get is an NTE sub, so we buy it and pass the savings along to the customer.

[guitaraddict]

gettin educated

Well dont I feel a little foolish, but im learning so i guess that how it is done. Thanks for leaning me while helping out

[rf7]

I use Datasheet Archive - Free Datasheet Search Engine - PDF Datasheets - Data Sheet - Datasheet - Application Note - Free Texas Instruments Samples to look up substitutions. You have to double check the the specs to make sure that you can use it. And be sure and look at the pinout too, sometimes they vary.