When was the BC107 introduced?

I used Motorola RF power transistors for my stereo ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

I loved tunnel diodes, and the slower ones were cheap, right out of the Allied catalog. Germanium Power Devices still makes them, I think, and the production process is amazing. Last one I bought from them, to fix an HP TDR, cost about $80.

Back when Haltek was still around, I found a bin full of TDs back in the dust. Bought them all for 10 cents each.

CK722's started at about $7, but got cheap fast. 2N107's (npn ge) were a buck or so from the start. But a dollar would buy a burger and a big frozen mug of root beer back then.

John

Well, yeah, you worked there :-)

After the original one blew I had a Motorola 6W RF transistor in a 10W FM rig because the 10W edition was too pricey for someone in college. Well, I could have dipped into the beer budget but there are some things man doesn't do.

--
Regards, Joerg

http://www.analogconsultants.com

Texas Instruments had an August 1954 data sheet for the commercially available "Silicon grown junction transistors", types 903, 904, 904A,

905 and X-15.

** Most folks idea of " commercially available " is when a product is offered to industry at a viable price level.

Supplying them to the US military for over US $100 each in 1954 hardly qualifies.

....... Phil

and

Ouch, that is expensive. But not if it fixes a TDR rig, of course. We had no Allied over there and distributors would not sell to hobbyists even if you fell onto your knees. At the university I joined the RF institute and a whole world opened up because suddenly distributors courted us. Heck, once I even netted a nice cigar.

We have a Halted store in Sacramento. Is that the same local chain? It's mostly surplus stuff and quite a drive from here. AFAICT it's the only such store left.

50c would buy you a nice 400ml Pilsener in Germany back then, about 80% of a pint. A brand name transistor could set you back eight of those. Too much of a sacrifice so we tended to improvise or use tubes. I believe said Pilsener now costs 2-3 Euros while transistors can be had for a dime in small qty.

--
Regards, Joerg

http://www.analogconsultants.com

and

We still have a Halted. Haltek, no relation, was driven out by the dot.com real estate bubble.

Halted (Hal and Ted) is famous for being offered Apple stock (by Steve and Steve) as payment for parts, and turning down the offer.

Heck, I can remember draft beer for 25 cents on Bourbon Street, and oysters for a dime.

John

That's a good reference. That was a TO-18 metal-can part, fairly advanced, perhaps more than the TO-18 BC107.

A popular plastic version, the 2n4401, came much later. In fact, didn't the TO-92 package arrive several years after the 2n2219? I remember Fairchild's epoxy package, which I used a lot about 1965. TO-105 and TO-106, IIRC. It was cool to look at, with its black dome and gold- plated leads, projecting through a frame. Except, ahem, eventually they made parts that sometimes worked loose.

The TO-92 package came later and looked rather cheap on the surface. Yes, it was cheaper to produce, but it was far more reliable. I'd guess about 1966 to 1967 for it to really take hold? Or was it later?

"Winfield Hill"

** See ABSE under Glob Tops.

Nostalgia, big time ....

....... Phil

These were TO-5's. Lots of gold.

Early IC's, opamps and RTL, were in that black-dome package.

First there was the GE plastic package, with a round base and a cylindrical top with a flat on the side. The very top was concave. The early units used a brown translucent epoxy and were photosensitive as hell... that caused all sorts of mysterious effects, hum and offset shifts and such.

John

Ah, those were the Sperrmüll days, the foundation of my electronics activities as well. Mostly old TV sets, sometimes even color (with those big-ass PL519 tubes). Precious few transistors. My hobby electronics book mostly called for the AC122, and I owned about six of them total, which were carefully rotated through projects.

But I stripped the PCBs of those TV sets bare. Life became more heavenly the day my dad gave me a desoldering pump for Christmas. Still have boxes full of parts in my parent's basement.

Sperrmüll is mostly gone these days, but I still can't just pass a pile of trash when I see it. And fortunetaly there is one right across my office where other people from the labs occasionally dump stuff. Just last week I rescued a PCB with five PA88 HV Opamps on it.

robert

Yes, the "Sperrmuell" was a cornucopia for parts and inspiration to build new projects. The kids today missed the sperrmuell, but they don't knew it! :-(

Jorgen

On a sunny day (06 Mar 2007 20:49:17 GMT) it happened "John B" wrote in :

BC107 was already in radios around 1969

I would have to think hard, but in 1968 I used some IIRC.

I also have this "defect" from the young hobby days. Mostly old tv sets, with IF stages that provided invaluable tunable ferrite coils. Worked just great for SW bands.

Those big metal IF cans often came with germanium detectors, OA91 was it? Excellent diodes. And the huge OC transistors. The salvaged PL519 tubes were used for rf amps. Than the pots, speakers etc.

Its hard to shake this "defect" off, the thrown-away electronics just "calls" for inspection, even though you know its not worth the trouble nowadays.

SioL

projects.

Its too easy nowadays. I wonder what would come of us guys if we had everything, like todays kids do.

Back than you'd usually start with some kind of radio related projects and would eventually develop a very good feel for the analog stuff. Nowadays you'd probably be starting with digital and never get hands-on experience with analog, unless you really had to.

SioL

would eventually develop

experience with analog,

Nowadays elementary school kids have "walkie-talkies" that can reach any telephone on the entire planet, MP3 players and whatnot. It's hard to build something yourself that's cooler and/or cheaper than all the consumer stuff already on the market.

robert

Recently I passed by a pile of junk in which I immediately spotted a stereo amp. I stopped and pondered if I -- wife, kids, PhD, decent salary -- should really pick it up and cycle one-handedly all the way home like in the olden days. Then I thought I had to do it just out of fidelity to myself -- what if, as a kid, I could have looked through a time machine and seen myself passing up such a gem? I took it, replaced a blown fuse, and it's as good as new.

robert

The black round domes were popular in Japan much longer than here in the US. I had a 1980's era Kenwood stereo that was peppered with those transistors.

Remember the glass Ge transistors and diodes? Very popular in Europe. After a while the black lacquer would flake off and they became light sensitive. Happened a lot in mixed tube/transistor TV sets. OTOH you could make nice and pretty fast light detectors from these for little money. A Swiss army knife to scrape the paint off was the only required "production tool".

--
Regards, Joerg

http://www.analogconsultants.com

John Larkin sez:

My understanding is that that the two split up over business disagreements. Ted opened HalTed and Hal kept HalTek. Hal now owns (or did last time I was in that Mt. View neighborhood) a surplus test equipment store, stocked to the hilt with Tek and HP equipment. Looked like he was doing a firesale business...

Hindsight...

--
John English