Maker Pro
Maker Pro

Need a few obsolete part numbers

T

Tim Williams

Jan 1, 1970
0
Ah, but SiGe (strained SiGe) is a new thing. Not pure Ge like those shitty
transistors I removed from a 1960's organ. ;-)

Tim
 
C

Chris Jones

Jan 1, 1970
0
Ignoramus19284 said:
Anyone would care to post smoe part numbers for obsolete (not selling
currently) electronic parts, thanks

i

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.
 
P

Phil Hobbs

Jan 1, 1970
0
Chris said:
Ones that I miss:
EL2009 (90MHz amplifier with 1 Amp output current)

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

Cheers,

Phil Hobbs
 
R

Rich Grise

Jan 1, 1970
0
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 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
 
B

Barry Lennox

Jan 1, 1970
0
Anyone would care to post smoe part numbers for obsolete (not selling
currently) electronic parts, thanks

Siemens SO42P
 
K

krw

Jan 1, 1970
0
Late at night, by candle light, Spehro Pefhany


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

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

YD

Jan 1, 1970
0
Ever hear of SiGe? I hear it's all the rage in RF. ;-)

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

- YD.
 
C

Clifford Heath

Jan 1, 1970
0
Winfield said:
The mrf966 depletion-mode dual-gate GaAs FET claims Crss
of 40fF, typ, damn good, whereas the NE25139 and NE25339
are even better, 20fF.

Damn, looks like I got excited too soon. Here's what Bryan wrote in response:
I am well aware of these devices, as well the characteristics mentioned.
Thats why we are using the parts in the first place. However, as I
mentioned all of these devices have been obsolete for quite some time.
The NEC parts in particular are available on the surplus market but more
than 80% of what we have procured to date have been fake. Usually just
lead frame and plastic.

So what gives? Are the NEC GaAs FETs obsolete too? Is there any reliable
supplier of genuine parts still? Is there any other alternative?

Clifford Heath.
 
W

Winfield

Jan 1, 1970
0
Damn, looks like I got excited too soon. Here's what Bryan wrote in response:


So what gives? Are the NEC GaAs FETs obsolete too? Is there any reliable
supplier of genuine parts still? Is there any other alternative?

Clifford Heath.

How about Dee Electronics, 1350 pieces of the NE25139
(sot-143 package) available, http://www.dee-inc.com

Other dual-gate depletion-mode GaAs MOSFETs:
Toshiba 3sk240
Renesas 3sk239A
Nec 3sk299
Infineon cf739

Enhancement mode:
Toshiba 3sk292
 
C

Clifford Heath

Jan 1, 1970
0
I passed your message to Bryan, who responded:
How about Dee Electronics, 1350 pieces of the NE25139
(sot-143 package) available, http://www.dee-inc.com
Sounds like a surplus cut reel. Not enough to guarantee a reliable supply and its still also obsolete. SOT-143 is > much larger and the cost of re-layout, BOM changes, engineering testing, qualification and authority recompliance > would normally outstrip the (usually inflated) cost of the parts themselves many times over. This is a typical
example of the problem rather than a solution.
All obsolete as far as I recall. 3SK299 is particularly troublesome as we use the U73 variant. 100% of parts
ordered from all sources over the last 12+ months have been fake. CF739 does not appear on the Infineon web site.
This is not a GaAs device.

I find it strange that in a situation like this, it's not economical
for *someone* to make a suitable part. Sigh.

Clifford Heath.
 
W

Winfield

Jan 1, 1970
0
Clifford said:
I passed your message to Bryan, who responded:


I find it strange that in a situation like this, it's not economical
for *someone* to make a suitable part. Sigh.

Clifford Heath.

I'm beginning to wonder if Brian, in a situation like this, isn't
a bit off base, applying rules suited for mainstream components to
end-of-life niche parts. What's wrong with a partial reel, if you
can order full reels from DigiKey if that's not enough? Surely you
two are complaining about how the market is no longer snapping up
the discrete GaAs MOSFET offerings, which must mean they've found
better parts for their purposes. Perhaps they've decided the small
extra bit of SNR available from a MESFET stage, over a microwave
linear IC, isn't worth the trouble of a bunch of discrete parts.
 
B

Boris Mohar

Jan 1, 1970
0
Come now, those are unreasonable old parts.
How about uA703 and later, the uA709 opamps.

SQ-10a Teledyne Philbrick op amp
 
C

Clifford Heath

Jan 1, 1970
0
Winfield said:
I'm beginning to wonder if Brian, in a situation like this, isn't
a bit off base, applying rules suited for mainstream components to
end-of-life niche parts. What's wrong with a partial reel, if you
can order full reels from DigiKey if that's not enough?

Are you saying there's a replacement part available from Digikey?
Or that he shouldn't bemoan the obsolescence of a part for which
no alternative of equivalent or greater performance is available,
even allowing for a complete redesign of the receiver? Nothing
short of a custom chip, made of available parts, cannot beat the
performance of his design... makes it hard for the little guy...
Surely you
two are complaining about how the market is no longer snapping up
the discrete GaAs MOSFET offerings, which must mean they've found
better parts for their purposes. Perhaps they've decided the small
extra bit of SNR available from a MESFET stage, over a microwave
linear IC, isn't worth the trouble of a bunch of discrete parts.

Well, when you have a receiver that's a key element in international
competition (amateur radio direction finding and radio orienteering),
sensitivity, dynamic range, and noise floor - considering the need
to stay within a low-power (hand-held battery-powered) budget - are
at a premium :).

Clifford Heath.
 
Top