A Salute To The Venerable 807 Vacuum Tube

[@bobweiss8682]

The 807 is essentially a 6L6 adapted for RF applications. Plate cap to handle high plate voltages, low loss micanol (brown) base, and some additional RF shielding. The 1625 (used by the thousands in WW2) is essentially the same tube with a 12.6V filament and a 7 pin base. After the war, the 807 was used as a horizontal sweep tube in a few TV sets, but was quickly "value engineered" into the 6BG6 by removing the additional RF shielding, and putting a cheaper octal base on it.

[@MojoMedicineMan]

I need a matched quad of NOS. I'm not sure, but I think I read that "Standel" built an 807 output amplifier once for Chet Atkins or someone like that?

[@amplifierexperts1983]

I designed and built an 807 based amplifier from scrap parts that I had laying around. I did use a solid state rectifier and the amplifier makes 50 Watts continuous sine wave with 05% distortion. Of course I'm using a public address audio output Transformer so the bandwidth is not spectacular but it was available Parts I had laying around.

[@thomastubeworks]

I think I was telling you another time but I have pile 1625 mostly NOS and dang some of those tubes are so beautiful just the quality in them is amazing and they all test extremely well after sitting around since the 40s, my Williamson amps are running 1625s and I’m still amazed at the sound of them, I think I’m going to try making a single ended amp with some of them after watching your 807 build. Only reason I got them over 807s is the price difference near me is massive, I could deal with the different base and 12v heater for the money saved

[@ElPasoTubeAmps]

I agree that the 1625 is just as good and the same except, as you say, for the 12V filament - and the socket. I used the 1625 years ago for a modulator using four in the output. I have been listening to this little amp every since and I do not tire of it. I am amazed.

[@thomastubeworks]

Enjoy your little amp David take care and talk to you again soon my friend

[@murrayabma5212]

@@thomastubeworks …but the top cap is sexy!

[@thomastubeworks]

@@murrayabma5212 I agree! the 1625s have a top cap also they are identical to a 807 if that’s what you meant

[@murrayabma5212]

Thank you for this series David! I hope you have good stock on 807 tubes, because prices are going up now…

[@lego40404]

Yeah they’ve been going up past few years now.

[@lucancherby]

Western electric 300B prices are going through the roof. I've seen a pair going for $2400 on eBay crazy

[@bob_mosavo]

Awesome‼ Thanks 👍

[@johnnaighley9252]

I also like the 807. It's a real magician. Specs show that you even can operate the 807 in Class A at a plate voltoge up to 500 volts in single ended mode as a pentode and it works great. You cannot do this with the 6L6! The 807 bottle was also inserted in the amplifiers of German Bergmann jukeboxes in the mid fifties. There the 807 worked in pentode mode in push-pull manner with autobias and produced 20 watts.

[@jimcatanzaro7808]

6l6 are the same