Yikes!

Interesting. The Fairchild data sheet shows 200. Ditto TI. ST says 400 mA for the Vcc or Gnd pins.

The Onsemi spec is strangely worded. I'm not sure what their Icc spec actually means... "per Output Pin"

John

HA! My Radiotron edition is 1953!

Original price: $5.75

John S

I tend to get niche work in areas where I make use of stuff I knew about 25 years or more. As in likely to not get much more obsolete than it already is.

Often including long-existing workhorse ICs that became available in surface-mount reduced-size packages - indicating that their manufacturers likely consider them "reasonably current". Such as

There are things I do with SOIC versions of 4000B series, LMC555, LM339, and LM324, and through-hole 14-DIP TLO84, for profit, and for fun. And, for low cost of such jellybeans.

I remember those, and times when those were the "usual big job" packages, such as 2N3055.

Oh, I remember 2N5629, 5630 and 5631, and their PNP compliments

They were a little slow, but very robust.

Sometime afterwards, TO-220 and TO-247 largely replaced TO-3. Last time I used a TO-3 was before 1991.

That sure looks cool, but the economics don't make much sense. You have to glass-seal the resistors and caps so they don't outgass, and you have to replace them all when the tube part dies.

Victoreen used to, maybe still does, make high-ohm glass-sealed resistors. But then, I can buy a 1T resistor in 0805.

John

I have the 3rd edition, 1941. The really valuable one, the one audiophools love, is the big red one that you have, 1953.

Radiotron is sort of boring. Mostly audio.

I think my oldest electronics book is Principles of Radio Communication, Morecroft, 1921.

John

I don't do much monostable work. I make lots of use of 555s in astable mode. Also, there was a time about a decade ago when I made some use of them as beefy buffers because they cost less than "MOSFET drivers" did.

An LMC555 is smaller than a 4049, 4069 or 40106 and has more predictable hysteresis thresholds than the 40106. (4049 and 4069 don't have hysteresis, and do incur high power dissipation if input voltage moves slowly.) And when I use them, LMC555 usually draws less than a milliamp for feeding itself. (In low-power-critical situations, I go for CMOS drawing close to zero power when input voltage spends time at one supply rail or the other.)

Its actually called the 'Machinery's Handbook'

Lots of stuff in there for mechanical design, gear pitch design, thread design, fluid flow tables, water column weight, etc... If you don't have on, your not a mechanical engineer.

Cheers

They changed the name, deleted "Radio" at some point. Pity.

John

He should know that. 'Machinery's Handbook' is mentioned quite often on the metalworking newsgroup he trolls. news:rec.crafts.metalworking

Only inductors, it needs a rather long wire antenna, the older tube versions and sets didn't have controlled feedback. I think that's the trick they used to get the undesired capacitances down.

For Loewe it must have been good and profitable business. They made those tubes for a long time.

Another advantage was repair. You didn't need a technician to find which part went bad, changing the tube usually fixed it.

George Herold schrieb:

Hello,

the woven coil reduces the unwanted capcitances between two adjacent windings.

The two woven coils is indeed a variable transformer for the coupling of the receiver to the antenna. By moving of one coil, the receiver is adapted to weak or strong transmitters. Just a manual gain control.

Bye

But changing a tube usually fixed a radio. People pulled out the tubes, took them to the free drugstore tube tester, bought replacements for the bad ones.

John

From oodles of radios and TV sets I repaired as a kid most had more hardcore defects. Nasty stuff like an increasing popping in the audio after 1/2h or warm up. Those were the "pleasures" of self-healing caps. Instead of oozing out and leaving that telltale ant poop evidence you couldn't see anything. And the meter wouldn't show anything either.

Once a TV repairman asked me how on earth I found one (on a set he'd put at the curb for garbage collection). I had made a little sniffer loop so I could detect isolation breakdowns via the antenna input of an AM radio.

Then there were the caps that became leaky but didn't pop or poop, mostly of the Wima brand. You had to have total silence around you and then listen through some PVC tubing, see if you could pick up an ever so slight splattering sound, similar to chili when it begins to boil. Another brand let off a hiss instead. Other sets had resistors that decided it's time for a hefty raise. They went from 100k to 1M or so. But the real cussing happened when discovering infinite ohms at an IF coil where the schematic shows a coil. Flux left on the ends ate those away at times.

John Larkin schrieb:

Hello,

at that time in Germany, Telefunken had a lot of patents for tubes and radio receivers. Every other company had to pay licence fees to Telefunken, the pay was not per tube, it was per tube socket. Therefore it was economical to pack several tube functions into one socket, it reduced the amount of licence fees to be payed.

Bye

pre-date

The Radiotron has a section on designing transformers covering items that I've not seen in any other book I have run across. Such as estimating temperature rise based on the geometry.

John S