Datasheet for vintage Transistor - Page 1
Forum section: electronics / repair

author: Teknow
author_rank: Regular Contributor
timestamp: February 16, 2017, 08:21:16 am
content: Hello!I happened to have a bunch of Fairchild transitors F198023-2 (NPN) and Motorola M198024-2 (PNP), Beta 30, unfortunately I couldn' t find any datasheet or information. The transistors are TO18 and some are a bit smaller. Thanks for any help.

author: amyk
author_rank: Super Contributor
timestamp: February 16, 2017, 10:17:28 am
content: NTE128 and NTE159 seem to be the modern replacements.

author: testian
author_rank: Regular Contributor
timestamp: February 16, 2017, 12:13:07 pm
content: They where also used by some people as 2N3904/3906.

author: Teknow
author_rank: Regular Contributor
timestamp: February 16, 2017, 01:09:01 pm
content: Many thanks Amyk. There are a lot of replacement transistors for example 2N3904/6 or even 2N4124 etc depending on the circuit and function. I am more interested in getting the original Data sheet and curves. I presumed it has an ft as high as that of the 2N2369. I also think it's a Tektronix or a HP part as I got them from a repair and calibration center.

author: tautech
author_rank: Super Contributor
timestamp: February 16, 2017, 08:05:02 pm
content: Quote from: Teknow on February 16, 2017, 01:09:01 pmVery likely. A quick look at Spheres x ref list doesn't show them but there's a big Tek x ref that you need to download and check against.http://www.sphere.bc.ca/The list is there but you have to hunt for it and they ask that it not be linked, 22Mb and 400+ pages IIRC.

author: Teknow
author_rank: Regular Contributor
timestamp: February 17, 2017, 08:19:46 am
content: Many thanks Testian and Tautech I'll hunt for it.

author: Teknow
author_rank: Regular Contributor
timestamp: February 17, 2017, 03:09:02 pm
content: Unfortunately, I found nothing in Tektronix, but through intensive search I came across NTE123A (TO18) ECG123 and NTE159.

author: cncjerry
author_rank: Unknown
timestamp: February 18, 2017, 04:07:49 am
content: The NTE/ECG 123 and 159 replace any number of transistors in general purpose use but in reality they are nowhere close in any specialized circuit.

author: Teknow
author_rank: Regular Contributor
timestamp: February 18, 2017, 09:18:30 am
content: Thank you CNCJERRY, absolutely. I hoped they were better than 2N3904 and 2N2222A at least. I suppose the 198023 resembles the 2N2369 in its RF merits. I designed a vco with the 198023 according to the 2N2369 specs for 2m and it worked fine!

author: cncjerry
author_rank: Unknown
timestamp: February 18, 2017, 08:31:48 pm
content: That HP site, Sphere I think as the other poster mentioned, is a good site to check.The other thing you might consider doing is looking in some of the old HP schematics to see if you find them. A lot of HP parts lists had the complete part number on them where the part itself was missing the first two digits. One other thing you can do is make up a small amplifier not unlike the 2n5179 HF amp and run a signal generator thru it to find the upper frequency limit. That's the issue with the ECG123 vs the 123A, etc. where they use it as a general purpose small signal replacement.

author: Teknow
author_rank: Regular Contributor
timestamp: February 19, 2017, 03:01:17 pm
content: I'll surely do this next and report my results.