The first pocket transistor radio

[Steve Eddy]

Originally posted by davidsrsb
If germanium devices got more than a little warm they died.

Yeah, they were hardly the most robust solid state devices.

se

[Tube_Dude]

Originally posted by Mark A. Gulbrandsen
I just love that T.I. ad from the 50's...

November 1953...two month after I was born ...in september 1953...

[Steve Eddy]

Originally posted by Mark A. Gulbrandsen
I just love that T.I. ad from the 50's... "20 Times Tested" Today you're lucky if they test every 20,000th device!

Yeah. But materials processing and manufacturing have come a long way since then too.

se

[clem_o]

My brother has a Sony radio from 1972 - if I recall its supposed to have been a 'first IC radio'. About as big as a match-box. I remember seeing it when I was a lot younger, not sure if its still around!

Cheers!

[jackinnj]

i didn't get my first transistor radio until 1961 -- my dad gave me his when he purchased a new one -- it was a 7-transistor GE model and it is somewhere in my mother's house! Up until I received this radio I used a crystal set from a Remco kit to listen to the late-night talkers and baseball.


http://people.msoe.edu/~reyer/regency/QST_3-53-p97.jpg

[SY]

Jack, you're probably old enough to remember the transistor wars? This is a 10 transistor radio, for another $5 you can get a 15 transistor radio. Top of the line is a 20 transistor radio; that one must REALLY be good!

One of the electronics mags at the time (Electronics Illustrated, I think) ran an expose, where they bought a bunch of the high transistor count radios, examined the guts, and found about 5 transistors actually working, the rest either diode connected or not connected at all.

[dnsey]

Rather like the 'stereo' ones, which had one speaker mounted in the centre of a cardboard tube, with grilles at each end!

Who mentioned BO**

[Original Burnedfingers]

What I remember the most was how long the battery lasted in one of the old transistor radios. The more transistors the less life on the old 9 volt. I had one that would spend a battery in about an hour.

[davidsrsb]

Originally posted by Tube_Dude

Triodes only for the 3 terminals , because the impedance "looking" in the collector of the transistor is very high ( hundreds of KOhms ) it look more , like a pentode .

Germaniums had much lower output resistance than silicon transistors, far more like a triode.

I remember a physics practical around 1971 measuring transistor curves. The task was written with an AC128 germanium in mind and I was very confused by the silicon device that I was given.

[Tube_Dude]

Originally posted by davidsrsb
Germaniums had much lower output resistance than silicon transistors, far more like a triode.

Look at the specifications in the data sheet.

http://people.msoe.edu/~reyer/regency/ti_ad_11-53.jpg

Collector resistance (minimum ) ... 0,2 MOhms - 0,4 MOhms..

The proverbial imperfect constant current source , hardly a triode at all , I'm afraid...

Cheers