are dei transistors any better now?

[9C1Driver]

i want to click the order button on a new texas star dx1600 sweet sixteen amplifier but im a little apprehensive. the output transistors are dei and i know they don't have a good track record. my texas star 500 with dei's has been running flawlessly so far. now that its been quite a few years have the dei transistors gotten any better as far as reliability? i know that if you run them within spec there shouldn't be a problem, which is how i run my gear but i don't want to pay the million dollars to put Toshiba's in it.

To answer your question DEI transistors have not gotten any better or worse, they are what they are. The only update is they are no longer made so what ever supply of them are left is all there is.

 

[Onelasttime]

You know we do not even know what Chinese semiconductor company makes DEI bjt's!!!

 

[Onelasttime]

I got a used DM 8 Pill with all Toshiba 2879's for $500. Not saying you will find that exact deal, but maybe you are not looking hard enough? Craig's list, Facebook, eBay, Let Go, CB & HAM radio forums... and many, many more sites have the potential for providing you with the right used amp without having to settle for falsely advertised products. Ham fests are another resource.

A DEI, PP or HG 2sc2879 is not a real 2sc2879. PERIOD.

You know, it shouldn't be past the realm of possibility if they (the Chinese) can make reliable exact duplicates of the venerable 3-500z & 572B vacuum tubes but can't the get the 2sc2879' transistors right yet. Who knows, Patent issues? Toshiba threw away the dies? Beryllium? Lead? Not enough demand? Maybe 10 years from now? Wake me up when they do make them again or I'm going to have to switch to 50V.

The problem is that part of a transistor is grown and that is one problem. The next is that companies like Toshiba and Motorola do not use off the shelf machinery they build their own machinery. So if you do not have the recipe for the waffers and you do not have the machinery that places the transistors on the die you can not duplicate them. It would be like some guy in his back yard attempting to make a Ferrari V12 in his back yard with out knowing the exact alloys used, processes used and with out the same machinery used. You might make an engine that looks the same and some of the parts might interchange as well but it will never be the exact same thing.

The reason Macoms MRF454 is the same and drop in for Motorola parts is because they have bought the recipe and the machinery and license rights! I am sure companies could do that with Toshiba parts if they wanted to spend the money but they do not do they?!?!

 

[psycho]

The DEIs can't handle the abuse a Toshiba can and the output is definitely not up in the Toshiba category.....but still OK.
I would use DEI transistors before I would ever put crappy Chinese made Nexen, Kumho or Nitto tires on my pickup.
If the Chinese make nuclear weapons and ICBMs with their wonderful quality, we have nothing to worry about.

 

[Tallman]

I will say this about the DEI transistors, they are better than nothing at all. If you have an amp you need to fix they do fill the hole in the circuit board better than nothing.If you install them just turn the A/B bias down so you don't exceed the maximum rating of the DEI parts. Drive them easy.