Need a few obsolete part numbers

see also

Best regards, Spehro Pefhany

Thanks, just what I wanted.

Hope This Helps! Rich

Come now, those are unreasonable old parts. How about uA703 and later, the uA709 opamps.

TL011 current mirror, *sniff* MRF966 dual gate GaAs FET

RIP.

Cheers,

Phil Hobbs

ouch. ;-)

Well, gotta give 'em some credit... they're starting up a new factory in Elbonia based on the new unobtanium oxide semiconductor manufacturing process.

eh

Would that be the UHF FET a friend of mine is lamenting? He builds RF sniffers used in transmitter hunting for which he's bemoaning the absence of a credible replacement GaAs FET, and can't achieve the same noise and dynamic range performance with any of the UHF chips.

Probably. Its reverse capacitance was so low you counld make a 70-dB isolation amp at 100 MHz in one stage, with one FET and two resistors--you just connected G2 to source, and away you went.

Cheers,

Phil 'born too late' Hobbs

NEC makes two dual-gate gaasfets, NE25139 and NE25339.

John

That's what I *love* about Usenet. I figured if anyone had an answer for Bryan, it would be Phil or you, and *both* of you answered! I'll forward your response to him and I hope it will solve his problem. If it does, you'll have his eternal gratitude!

Clifford Heath.

The mrf966 depletion-mode dual-gate GaAs FET claims Crss of 40fF, typ, damn good, whereas the NE25139 and NE25339 are even better, 20fF. But I see NEC's specs are all with Vg2s at +1V, a bit of a pain with the bypass requirement, etc., compared to 0V ground used for the mrf966 specs. John, have you tried using the NEC FETs with grounded G2?

Late at night, by candle light, Spehro Pefhany penned this immortal opus:

Don't forget AC128 and AF115. Which reminds me, were any ICs made of germanium?

- YD.

Yup--and don't think past tense:

Ones that I miss:

TDA1514 (low distortion audio amp) BY8418 (18kV diode, used to be cheap) MAX038 (20MHz function generator IC) EL2009 (90MHz amplifier with 1 Amp output current) also all the old Plessey RF chips SL6440 etc.

I have a career's worth of those in my drawer (meaning about 20). Very nice--sort of a turbocharged LH0063.

Cheers,

Phil Hobbs

I have some nagging memory of some counterpart of the CK722, that wasn't the CK768, but can't remember for the life of me what the nubmer was. Or _was_ it CK768? I remember that one was PNP and the other was NPN, but this was about 50 years ago, and you know what time can do to memories. ;-)

So, anybody either remember that, or have a record somewhere?

Thanks! Rich

Siemens SO42P

Ever hear of SiGe? I hear it's all the rage in RF. ;-)

Late at night, by candle light, krw penned this immortal opus:

Of course I have, but that's not what I'm after. ICs made of pure Ge before Si became all the rage?

- YD.