Sounds right, Tom.? MRF935 or some part number like that had 4 leads in an X pattern.? 2 opposite were emitter, and base lead was cut at an angle to distinguish it from the collector.? B and C opposed was handy for soldering to microstrip, and the E leads got soldered directly to the ground plane for a low-inductance path.? You could even drill a hole in the board and drop the package in so that the leads were flush with the surface.? ?HTH.? ? ? Jim Ford?
On Fri, Jul 5, 2024 at 11:25 AM, Tom Lee
<tomlee@...> wrote:
Those look like some surplus transistors I bought from Poly-Paks (or
possibly Meshna) in the 1970s, but many devices were packaged similarly,
so it's hard to say with any confidence what yours are from a photo.
Mine were PNPs, with beta values around 50 and breakdown voltages in the
20-30V range. I remember making a crude ft measurement and getting
values north of 300MHz (about the limit of my janky high-school setup).
They were faster than the 2N3906s I used for comparison. I built a lot
of little 1- and 2-transistor radios with them, back in the day.
I think I still remember the pinout: Looking at it with the red dot on
top and the leads oriented to form a T, the left and right arms were the
collector and base, respectively, and the bottom stem was the emitter
(I'm most certain of this one). A quick diode check with your DMM should
reveal whether your device could be similar.
-- Cheers,
Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
420 Via Palou Mall
Stanford University
Stanford, CA 94305-4070
On 7/5/2024 6:56 AM, Renaud F5ZR via groups.io wrote:
> Hi,
> Sorry because this is not an HP topic, plus it's I believe it's a long
> shot.
> I got 25 of those:
