thank you, item sent back

looking to pick up a rk3 - anyone have good experiences with these in a tiptop mantis? should be well under the 3A/1000mA for +12v at startup, but i’m slightly cautious at how the power is distributed to the ‘zones’. thanks! A Mantis supply should be okay. Just don't try to use an old Happy Ending ...

thank you sir--reposted on FB

Buy 2 and set them for different octaves....otherwise I doubt it will happen.....

I put this on Facebook but it's too funny not to share here..... Ever wonder where all those subminiature tubes were used? In monstrosities like the AN/ARC-65 aircraft radio. This is only the radio "chassis", in its sealed and pressurized canister. There was also a big ugly control box, an antenna t...

TM3 VCO schematic

just sent two D2k to Detroit Modular--give it a few days to arrive....

The Pingen Detector. A tube so obscure it's not listed in Tyne, Stokes, or any other book about early electronics that I can find. Made in Toledo, Ohio, by a company that apparently lasted less than a year (1922). People yammer about the "big hits" but no one keeps track of the misses.

Tube and radio collectors know the name Blue Bird very well. Two well-known radios carried the name. Less well known was the Blue Bird tube company, who made their own offbeat types and went out of business in 1931. (Note the typo on the box, and don't bother Googling this.)

On thing I'm curious about -- can the Drum/RK4 circuit filter audio yes but it's not a really good sharp filter. We use it because it requires one tube, and power consumption is one of our biggest problems. As I've said before (and you probably missed): we could make an all-tube diode ladder filter...

PS: don't sell yours, we discontinued it. Only 5 left and all spoken for by dealers. It's becoming too difficult to build and I'm having trouble finding reliable suppliers for certain things.

If you want to build something similar, get three RK4s and two cymbal modules.

What was a World War 1 "aircraft radio" like? It was like this SCR68. Imagine flying a plane, being shot at, and having to also communicate via radio. Using Morse code. Why are the transmitting tubes inside the main tank coil? There must have been a reason--however insane. it's generally a bad idea....

FatRocky wrote: ↑

Thu Nov 26, 2020 10:44 am

do you have schematics for this

Sorry can't remember, I think it was a modified TM5 or something in that area.....Zerosum did what he did, I didn't save any schemas

lol great thread Modern power supplies can source 10s of amps without complaint. And we are STILL getting complaints about people buying one RK module, which drags down their cheap Euro power supply. "It's broken!! You broke my cabinet!" Apart from power amplifiers, speaker crossovers and similar hi...

Old filter circuit used in Wretch. Similar scheme was in the TS22 and TM2 and R-52.
(Bass version used 0.01 and 0.022 capacitors in the feedback loop)

I finally found the TM7 schematic. Took hours of digging in boxes. Thank me any time. Compare to the TM5. Shocking how similar they are, eh? It's disgusting.

not posting any more schemas until someone fixes this goddamned forum. It kicks me out when I try to do a search or stay logged in for more than 15 minutes....

here's Rocky's module. now if we can just figure out return shipping.....

"I have never before seen such a complex 5” CRT. It is a 54DGP11 and is about 18” long. It has 4 guns with 27 pins on the 3.5” diameter base. There are 16 caps around the tube and there are two separate HV anode connections. There is hardly anything on a Google search. I know the P11 is fast but wit...

QK496 magnetron, used in a radar jammer (thus the "Confidential" sticker). Dan Stocks in Australia found this one. Apparently its frequency range makes it perfect for jamming the Wi-Fi band, if someone is so inclined.....

totally different circuits but roughly the same--a preamp with a lotta gain and adjustable feedback to make it unstable.
Sounds awful, don't buy it.

Hmm. That explains everything. I started this post and now I have changed my mind now knowing this. If only ten people were allowed after 2009 then good riddance. No wonder it didn't get "foot traffic". That's not all---the owner also had a robots.txt file that blocked search engines and archive.or...

This Thomson-CSF tube is from a 120 kW transmitter. Filament uses 35 volts at 575 amps. The anode at the bottom has to be put in a giant water-cooling jacket (distilled only!) and the upper stem has to be forced-air cooled. All isolated from ground electrically because there can be 20 kV on the anod...

Phil Florig shares some of his largest tubes: