The AM Forum

A friend has a bunch of these fine TO-3 parts. Alas, it seems to be a house number. They cost $12 on a Venezuelan surplus page where '3055s are $1-3, so it must be something, but no one's divulging the specs.

nothing in any of the old cross references I have.  What is it used in?

Might be common down in South America. Here's another selling the same code:
https://www.armazemautomotivo.com/produto/transistor-2311-4358_MLB1492664692

I have no idea what it is used in. There's a bin-box full of them, all new unused. The box came from cleaning out the shelves of a surplus store, there it was glittering ike a silver mine.

It is apparently most popular down South because it's advertised in secondary and DIY markets in Central/South America, and there are some possibilities that it was used in manufacturing a product marketed there but not in the USA. RCA was manufacturing in Mexico and elsewhere to the south.
It must be popular. It's sold new as well as used / removed from equipment in that region.

https://listado.mercadolibre.com.ve/rca-2311-4358

hey I just want to see how they can be useful.

My friend just texted, says he has about 40 LBs of them!

With 40 pounds of them to play with, have him send you some to "test" - see what it takes to blow one up and go from there.

My guess is it is a voltage regulator or audio output transistor.  Yep, get some and experiment.

I pulled out my almost 3 pound 1985 RCA replacement guide and your transistor, 2311-4358 was listed. It maps to a Darlington SK-3182. The SK-31382 maps to a NTE243. Here's the NTE243 data sheet to give you a clue to the specs of your transistor.
http://www.nteinc.com/specs/200to299/pdf/nte243.pdf
The brief RCA spec indicate collector current as 10 amps; NTE spec indicates 8 amps
According to their stock inventory info, it seems to be a common item.
The RCA replacement guide also makes reference to BURROUGHS but no info regarding it.

Thanks Pete!
I wish that old RCA catalog was online somewhere!
There is a lack of scanned semiconductor catalogs and databooks, some day this will be a sore regret in the hobby.

PM me your address and I can send some to you, very grateful.

This RCA replacement semiconductor book is about as thick, if not thicker, then the older Manhattan phone book.

Thanks for the offer, but the last thing I need here are more parts floating around.  :D  Remember manuals are my thing.

However, there are probably several Hi-Fi manufacturers that used Darlington semi's in the TO-3 package in their audio output stages so you might want to post on ebay or other "For-Sale" forums.

i think Pete has nailed it. :)

I have an old NTE 14th ed. catalog given to me by an ECG/NTE dealer and it points to an NTE 243, a Darlington with a DC beta of 2500. The PNP compliment is NTE 244.

It could be used in a complementary-symmetry audio amp final with a 65v supply.

Phil 

Nelson Pass designed a Class A  40 watt amp using complimentary darlington transistors. I built one and it sounded great but it was very inefficient, being true Class A. It used a huge Signal brand power transformer and a big bank of "computer grade" electrolytics.  I am thinking the design was vintage late 70s, early 80s and was published in Audio Amateur Magazine. I still had one of the power transformers and lost it in the house fire.

Pat
N4LTA

I was sorry to hear about the fire. Some good uses for these transistors will show up. We already talked about DC regulators and quasi complimentary amps. 65V seems reasonable for a supply voltage. The old dynaco stereo 120 type circuit could be interesting.

Here is the original Pass A40 article.


https://www.firstwatt.com/pdf/art_a40.pdf

Pat