RCA 1A10/1A11 (TO-39) and 1C03/1C04 (TO220) ordinary or very special? Where in use ?

Status
Not open for further replies.
Not so sure what you mean by "special".

If you have an few of them, check parameters in datasheet and use them where those parameters fit, same with the BD750/751 you ask about in another question.

You might build a 70 to 100W amplifier with them.

Just as historical data, I bet the RCA representative successfully visited Sunn or Fender in the mid 70's , because I remember a couple power amps (in PA powered mixers) using RCA 1A/1B/1C series transistors.
 
From the old RCA databook, these are based on 2N3439 and 2N5415 high voltage transistors. Typically as you mention they are used in VAS and CCS stages of amplifiers. They don't seem "special" other than perhaps lower voltage fall-outs from the 2N number devices (175V rather than 250V).
The 1C03/4 are 100V epi devices (ft~5MHz) with a gain of 50 at 1A, so not bad as drivers, except I'd use faster devices. Might make a low power amp output device (10W or so).
I'm particularly puzzled why RCA chose to rename (some of) their transistors as their 40,000 series was quite popular. Probably we'll never know now, but no doubt some marketing guru's brainwave.
 
Not so sure what you mean by "special".

If you have an few of them, check parameters in datasheet and use them where those parameters fit, same with the BD750/751 you ask about in another question.

You might build a 70 to 100W amplifier with them.

Just as historical data, I bet the RCA representative successfully visited Sunn or Fender in the mid 70's , because I remember a couple power amps (in PA powered mixers) using RCA 1A/1B/1C series transistors.
This means, no Pro-electron code and no JEDEC - go to
Semiconductor Numbering Codes | Pro-Electron JEDEC | Transistor FET Diode
From the old RCA databook, these are based on 2N3439 and 2N5415 high voltage transistors. Typically as you mention they are used in VAS and CCS stages of amplifiers. They don't seem "special" other than perhaps lower voltage fall-outs from the 2N number devices (175V rather than 250V).
The 1C03/4 are 100V epi devices (ft~5MHz) with a gain of 50 at 1A, so not bad as drivers, except I'd use faster devices. Might make a low power amp output device (10W or so).
I'm particularly puzzled why RCA chose to rename (some of) their transistors as their 40,000 series was quite popular. Probably we'll never know now, but no doubt some marketing guru's brainwave.
I think so, too. But I am not sure.
 
Last edited:
Just as historical data, I bet the RCA representative successfully visited Sunn or Fender in the mid 70's , because I remember a couple power amps (in PA powered mixers) using RCA 1A/1B/1C series transistors.

According to the Peavey transistor substitution docs, the RCA1B05 was one of the recommended subs for the house numbered outputs on the CS800. The other was the MJ15024, which came later. The originals were probably selected 2N3773’s because they were Motorola and that was the highest rated part (SOA-wise) they made in 1977. The 1B05 was just a selected 2N5240 (if I got the number right) for higher beta. One of my Phase Linear 400’s - the older one with analog meters - has RCA1B05’s in one channel. The other has 2SD555’s which I seriously doubt are original.
 
Status
Not open for further replies.