The AM Forum

I thought these Western Electric 416B tubes were discussed in a topic about surveillance receivers, but I can't find it. I am looking for the datasheets on them. These are the planar? triodes used as front end grounded grid RF amplifiers. Here is pics of them including a picture of the socket, which I have never seen before.

Those were developed for the A T & T long lines microwave repeater amps and were the best tube available for ham VHF/UHF preamps. I had one on 2M ages ago and still have several NIB tubes; the guesstimated NF was around .75 to 1dB and was used ahead of a W2AZL design 417A converter. I still have that converter and it was tested a few years ago at 1.8dB NF which is better than the ricebox rigs. Not bad for late 40's designed tubes.

Carl
KM1H

Yep, planar triode (416A) developed in 1948.  The 'B' version came out in '52. Frame grid construction. 

Heater  6.1V @ 1.17A.
Plate 200V @ 30 mA.
Gain is 3 dB @ 100 mHz BW @ 4 GHz. 
Would run for 40,000 hours if not pushed too hard. 
Versions went to the 416D, made up to 1984. 

Be careful, they have Beryllia seals.

dg

That's quite an interesting history. Noticing the operating conditions, 6 watts dissipation - no wonder the surveillance rigs have blowers on them. Thanks very much, I ought to be able to check the nems-Clarke and the LTV receivers and make sure the tubes are running properly. These rigs have blowers to cool the tubes.

oh no... "they" have found it.

http://ansaht.altervista.org/phpBB2/viewtopic.php?p=487#487

If I remember correctly, the sockets were especially made for the 416 series. There was a WECo. "KS" part number assigned to the socket.

I bet they handle lightning better than a FET

The Italians and the Japanese have already "discovered" and tried every vacuum tube ever made - a long time ago now.

In fact the Japanese were buying up all of our stuff in the 60s and 70s, before most people in the USA recognized the value (or usefulness) and at a time when people thought that tubes were fossils of little or no value. The transistor was king! Ha ha.

Tons of WE stuff went to Japan.

Wish i was smart, i wuld have grabbed some for myself... :(

                    _-_-bear

The Chinese as well, Bear. 

I remember in the late 80s I went and helped California Electronics in San Diego load up a couple shipping containers of tubed stuff.  They had some government wierdo there with a checklist as to what couldn't be loaded up due to restrictions, but almost nothing they wanted was on the list:  They wanted TUBE stuff!

We thought they where crazy at the time, the owners where happy to get rid of the "trash", and I HATED loading the heavy tex and hp stuff into the containers..... BUT, I did get to outfit my bench for payment for 2 days 'hard labor'.

--Shane

In the early 90s I had a Harmon-Kardon Citation I, II & III Series Preamp, Tuner and Power Amp (in whatever order the numbers went, I've forgotten) that I'd paid $50 for back in the late 60s. They were all still working fine and one day I happened to mention them to a guy that was an audio dealer in old tube gear. He got all excited and offered me $1500 cash for the set right then. Hell, yeah! Done deal.

I asked him what he wanted them for, and he said, "I have a guy in Japan who'll take all of this kind of stuff I can get. I'll probably get $2000 to $2500 out of them". Didn't matter to me, since I'd just made $1450. I've just always wished I had more of them.

ldb
K5WLF