That depends. The original "H" process diffused the emitter and collector from each side of the wafer. Therefore, to achieve a given base width you needed the wafer thickness to be thin enough to allow that with reasonable diffusion times (though even then, a day was rather long). Larger wafers were thicker, so made the process difficult. That had to be addressed using epi layers, and that changed the nature of the device.
I meant technological advancement. You may not agree but i believe that some of the cheap so called 'fake' transistors can provide much better performance than older transistors like epi 2N3055 (epitaxial but still inferior to modern transistors). I'm posting a video where you can see that how rugged a good copy of c5198 is (although author believes his transistor is original but in reality it's not).
BEL is a silicon refinery to finished product integrated operation, and they are under the Defense Ministry, they will not give details.
Their collaborations were with some famous names, I do suspect they have some special processes.
For those interested, look at their website, components are a very small part of their business.
But in any case, it is better to use another improved device rather than speculate about process used for a device which is no longer used in fresh production of audio amplifiers.
Their collaborations were with some famous names, I do suspect they have some special processes.
For those interested, look at their website, components are a very small part of their business.
But in any case, it is better to use another improved device rather than speculate about process used for a device which is no longer used in fresh production of audio amplifiers.
And the SOA of newer devices is generally better than the old 2N3055 (H) now. Just to mention one, the MJ15003/4 handles 3A at 60V compared to 1.95A. Or the MJL3281A for higher ft, about 2.5A at 60V. (And the ONsemi 2N3055 now shows approx. 0.8A at 60V ... an improvement on the original epi device which was only 200mA).
I was tearing out old production lines in the 90's
Those lines were either sold to Mexico or went straight to scrap.
Later on most the big equipment auctions went on boats to India.
When whatever prez at the time opened up trade restrictions.
Most interest was injection molding machines and final assembly
insertion machines. wafer production machines have no idea where it went.
Old hard drive production machines all went on boats usually or stored/scraped
Those lines were either sold to Mexico or went straight to scrap.
Later on most the big equipment auctions went on boats to India.
When whatever prez at the time opened up trade restrictions.
Most interest was injection molding machines and final assembly
insertion machines. wafer production machines have no idea where it went.
Old hard drive production machines all went on boats usually or stored/scraped
There are at least twenty operations in India refurbishing old injection molding machines, they usually sell for 20-30% of the new price, so a big saving is achieved.
Machines are purchased in the USA for 'pennies on the dollar', and shipped to India, where a complete electrical, hydraulic and mechanical overhaul is done, and then they are sold to local factories.
Japan, China and other Far Eastern countries are also sources for such machines, sometimes brand new machines are up for sale due to many reasons.
Apart from CDIL and BEL, there are two other fab units with the government, making mostly military and space grade components.
I do not keep track of the private sector semiconductor makers here.
CDIL does have newer device in TO-220 and similar packs, and they do make some old transistors, worth a look.
I have no ties to any above named businesses.
Machines are purchased in the USA for 'pennies on the dollar', and shipped to India, where a complete electrical, hydraulic and mechanical overhaul is done, and then they are sold to local factories.
Japan, China and other Far Eastern countries are also sources for such machines, sometimes brand new machines are up for sale due to many reasons.
Apart from CDIL and BEL, there are two other fab units with the government, making mostly military and space grade components.
I do not keep track of the private sector semiconductor makers here.
CDIL does have newer device in TO-220 and similar packs, and they do make some old transistors, worth a look.
I have no ties to any above named businesses.
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I dont know if this matters. But BEL (Bharat Electronics Ltd.)
Dont make the 2N3055. They only make the 2N3055HV and higher 2N3773. Which is what I posted a picture off.
If it helps I can cut open a new unit and take pics under a USB microscope.
This is their web site. Maybe you can find the info your interested in.
https://www.bel-india.in/
There may be better options out there but after building many amplifiers. Using Chip amps / STK / Complimentary / Quasi Complementary. Using all the latest greatest fastest lowest noise transistors. This is the sound I liked cause it reminded me of my childhood. As kids we had an Akai AM-2400 AMP. Which used a 2SD428 as the main driver. I have noted down most of the transistors used in this amp. And where possible try to use them. Problem with these 40+ year old amps is finding the exact parts used is hard.
Like on this amp there are 8 BC149c transistors used. But 2 have been replaced. So either I find 2 old transistors Or I need to change all 8 to the new transistor. (Its an OCD thing the amp works fine).
If I can find an un molested Akai AM2400 in my country I plan to just buy it. So far the few units I did find have tons of parts changed. Very few are still on the original parts.
Dont make the 2N3055. They only make the 2N3055HV and higher 2N3773. Which is what I posted a picture off.
If it helps I can cut open a new unit and take pics under a USB microscope.
This is their web site. Maybe you can find the info your interested in.
https://www.bel-india.in/
There may be better options out there but after building many amplifiers. Using Chip amps / STK / Complimentary / Quasi Complementary. Using all the latest greatest fastest lowest noise transistors. This is the sound I liked cause it reminded me of my childhood. As kids we had an Akai AM-2400 AMP. Which used a 2SD428 as the main driver. I have noted down most of the transistors used in this amp. And where possible try to use them. Problem with these 40+ year old amps is finding the exact parts used is hard.
Like on this amp there are 8 BC149c transistors used. But 2 have been replaced. So either I find 2 old transistors Or I need to change all 8 to the new transistor. (Its an OCD thing the amp works fine).
If I can find an un molested Akai AM2400 in my country I plan to just buy it. So far the few units I did find have tons of parts changed. Very few are still on the original parts.
I guess there really isn’t a need to make anything but the HV version anymore. If they can make a 3773, surely their 3055 would be good for 100 volts. Especially if their main market is the military. We have places around here that make old mil-spec parts too, but they want absolutely STUPID money for them. Not just post-pandemic stupid, but stupid stupid. Just so they can deliver something to an exact SCD, even if it would work just fine dropping an MJ15024 into it. Gotta love the brain power at work.
The D428? Haven’t seen those. Plenty of D427, the little brother to the 424.
The D428? Haven’t seen those. Plenty of D427, the little brother to the 424.
Rochester. Yep, had to order from them before. pricing is beyond stupid, good business model I guess. Your client base is over a barrel.
Watch out. Their 2N3055HV may be culled 2N3773 that can't deal with full voltage. Never assume anything! All I know it that it doesn't pay to use anything but the proper parts from an authorized distributor.
Watch out. Their 2N3055HV may be culled 2N3773 that can't deal with full voltage. Never assume anything! All I know it that it doesn't pay to use anything but the proper parts from an authorized distributor.
I bet the solidstateinc.com post 434 fab department is a silk screen table, and a paint brush.
Address in NJ is a tip-off. Original RCA fab in NJ is now a county park. An open field.
I am tempted by the CDIL 2n3055 for sale on Ebay 10 for $5. Ships from India for $35. Why would they bother to import garbage from ***** to resell to the US? CDIL has their own fab in India.
I've got about 9 Apex AX6 to build for Hammond organs that have a power amp with 7199 EF86 and 7591 tubes. Tube Amp heat ups the room and tubes are unobtanium. 35 watters will be 48 v rail. 6 channels were 6BQ5 PP for only 7 watts, 3 are 7591 PP for 35 watts 8 ohms (bass).
Address in NJ is a tip-off. Original RCA fab in NJ is now a county park. An open field.
I am tempted by the CDIL 2n3055 for sale on Ebay 10 for $5. Ships from India for $35. Why would they bother to import garbage from ***** to resell to the US? CDIL has their own fab in India.
I've got about 9 Apex AX6 to build for Hammond organs that have a power amp with 7199 EF86 and 7591 tubes. Tube Amp heat ups the room and tubes are unobtanium. 35 watters will be 48 v rail. 6 channels were 6BQ5 PP for only 7 watts, 3 are 7591 PP for 35 watts 8 ohms (bass).
Hi indianajo,
All due respect, but I feel your post is disrespectful. Clearly many fabs in developing countries use original equipment that at one point was cutting edge - in the USA. PCBs were once made with a silk screen and paint brush, not semis - so that comment is extremely disrespectful. Old Japanese equipment was also extremely high quality as were several other types of equipment made in other countries.
If you were going to resell semi's you would buy much higher quantities for one, and get a price break along with a deal on shipping charges. Of course shipping would be less expensive buying out of AliExpress from the same vendor most likely.
Last I looked, New Sensor makes excellent (real) new production 7591A tubes. I bought a set years ago for an amp I am rebuilding, and others I have redone. Never mind that a tube has about as much in common with a 2N3055 as an apple and an orange. Why even mention them (tubes)? What on earth is your point?
-Chris
All due respect, but I feel your post is disrespectful. Clearly many fabs in developing countries use original equipment that at one point was cutting edge - in the USA. PCBs were once made with a silk screen and paint brush, not semis - so that comment is extremely disrespectful. Old Japanese equipment was also extremely high quality as were several other types of equipment made in other countries.
If you were going to resell semi's you would buy much higher quantities for one, and get a price break along with a deal on shipping charges. Of course shipping would be less expensive buying out of AliExpress from the same vendor most likely.
Last I looked, New Sensor makes excellent (real) new production 7591A tubes. I bought a set years ago for an amp I am rebuilding, and others I have redone. Never mind that a tube has about as much in common with a 2N3055 as an apple and an orange. Why even mention them (tubes)? What on earth is your point?
-Chris
Check the addresses in Bloomfield NJ. SS, Inc. and NTE are two doors down from each other. They don’t make their own stuff - they buy from where they CAN, and re-mark it. If their source is good, then the part is. If it isn’t, well…..
I have seen RCA hometaxial 3055’s being sold surplus. So there are a few left on the planet, and SS, Inc. probably buys their share of them. Of course the volumes are small, so it can be sustained for a while. The problem is going to be when they are truly gone. Like NTE58/9. How much do you trust that they are really Sanken LAPTs? I’m sure at one time they were, but my money is on ISC - since there is demand and they are “making” them.
And last time I looked New Sensor was still being made in Russia. Which, for many people, might as well not be being made anymore.
I have seen RCA hometaxial 3055’s being sold surplus. So there are a few left on the planet, and SS, Inc. probably buys their share of them. Of course the volumes are small, so it can be sustained for a while. The problem is going to be when they are truly gone. Like NTE58/9. How much do you trust that they are really Sanken LAPTs? I’m sure at one time they were, but my money is on ISC - since there is demand and they are “making” them.
And last time I looked New Sensor was still being made in Russia. Which, for many people, might as well not be being made anymore.
Point is I need to build 9 SS amps to abandon these room heater tube amps. SS class AB produces 1/6 the heat of tubes for same wattage out. I could spend $180 with ON semi TO3 or maybe $50 with CDIL. Thanks chinoy & nareshbrd for the headsup.
And a company like solidstateinc selling 2n3055h from New Jersey is obvious (to me) not doping silicon wafers there. I have to say their neighbor NTE is an honest supplier. NTE datasheets leave most of the specs off, compared to the original part. Respect? no. I've bought some NTE, now replaced with ON & ST parts.
Not a lot of military surplus auctioned in NJ, either. I buy sometimes from a surplus house in Nebraska, that finds all sorts of really old parts, possibly from Offutt AFB or suppliers thereof.
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Neighbor? It’s gotta be all the same company. “Respect” for NTE is not universal. Lots of service people, ones with reputations to protect, avoid them like the plague. You CAN get burned. Doesn’t mean you always will. I bought a bunch of NTE284 when I found them in a bin for cheap. Looked like the original label had been sanded off, and the NTE number printed on. Cut one open and it WAS an original 2SD424. Been using the batch for years with no ill effect . Wouldn’t count on it today though. Might blow right up. But you could just as easily end up with an ON MJ15024 in there. Care to roll the bones?
Maybe but Digikey has close to 3k SS 2N3773 in stock, also check Element14 malaysia & Indias Robu.in (A well known indian parts supplier). Anyway i placed an order for couple of SS 2N3773 which i always wanted to keep for experiments because of its excellent SOA.