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I've seen some radios that had transistors that weren't even connected just to up the count. Leon Robinson ?K5JLR

Dave, I think that's right - TO-98. The 2N3391 rings a bell too. There were a number of them in that part range, that might be the right ones for good noise. I don't know if any newer, modern versions

The stainless steel lifetime warranty ones. I have 4, two I pickup at yard sales duds Aladdin replaced. Have another dud one of the original. They will keep Hot coffee drinkable for about 12 hours.

I thought of that once when I got hold of one of those radios and tested the extra transistors. About half of them were shorted. They were probably rejects or picked off the floor. ?? Bruce Gentry,

The large dewars are nice, but they have to have a very hard vacuum inside if you want them to hold LN2 for any amount of time... We're talking oil diffusion levels. Then, there is the problem of

?That would be TO-98. 2N3391? (By the way, that number is still in production but TO-92.) Dave Wise? ________________________________ Sent: Monday, February 22, 2021 3:48 PM To: [email protected]

I passed up a good size dewar at a garage sale for $5 about a year and a half ago! :-/ At the time I just thought that I'd never use it and I'm getting to the age where I need to be getting rid of

Maybe the makers of these excess-transistor radios were just being considerate, and provided spares. Or not. Ed

Ed, your posts are always full of great nuggets like these. Thanks so much! -- Cheers, Tom -- Prof. Thomas H. Lee Allen Ctr., Rm. 205 350 Jane Stanford Way Stanford University Stanford, CA 94305-4070

Tom, if you study some of the old Keithley electrometers, you may find the two E-B junction clamp. I believe it was sort of a trade secret, developed when they started using MOSFETs (the type was

The idea is by no means new.? There was a radio manufacturer named Midwest that used lavish numbers of lower power rated tubes (6K6) falling out of favor and cheap in parallel instead of one high

Speaking of noise... could you please start new threads for these interesting but unrelated topics? I looked at the 2N3904 and 2N5769 data sheets. They have the same max Ic (200 ma). The 3904 data

Ed Breya via groups.io wrote: There was a 15 transistor radio on the market around 1970.Only six were active. The rest had all three leads soldered together.

Got one here somewhere- kept for years just to show people. All three device legs soldered together to the same pad and no other connection. Of course you don’t know till you look at the copper

Jim Williams found an even more shameless example, where there were two dead transistors soldered to ... nothing. But they were counted in the AM radio advertisement. Tom Sent from my iThing, so

Dennis, here's a transistor trick that I'm sure was never taught in engineering. More of a marketing lesson. Back in the day, the number of transistors in a radio was a huge selling point - the more

looks like possible alternate (language) keyboard...but I did not notice the extras Renée

Jim Ford wrote: Probably createted by an MBA who had never even seen the \actual components.

You’d want a transistor with a fairly low max Ic, since the junction area would be smaller, and thus tend to have lower capacitance. The 5769 probably has close to double the capacitance of the

Morris, if you really need a noisy "Zener," look into an old series of GE NPN Si transistors, that are in an old-style package. I forget the JEDEC designation, but it's the one that looks kind of like