LA6NCA
So what do you do when you have a case of 12A6 vacuum tubes (over 200 of them). You mate one of them with an Arduino and Si5351 to build an 80M CW transmitter!
If you have ever diddled with an ARC-5 Receiver, then you immediately know the 12A6 is the Audio output tube. Think a 12 Volt version of a 6V6.
This video is in Norwegian but has English subtitles, so you know what is being said.
A couple of things to observe starting with an IKEA wooden box and the overall craftsmanship. Also observe how he made his own "Air Dux" coil.
I was impressed how he designed and built a miniature circuit board that houses an Arduino and Si5351. Its function is not as a VFO but as a crystal substitute. The very small circuit board is stuffed into a Crystal case and looks like an old-time quartz crystal. [QRP Labs (Hans Summers) sells a similar item and so it can be programmed to your favorite frequency. The cost is about $18.]
So, this is indeed a mating of a WWII vacuum tube with modern digital technology. In case you are averse to anything digital you could simply use a 80M Color Burst Crystal and therefore join the Color Burst Liberation Army (CBLA) under the capable leadership of its Commander, N2CQR.
There are many homebrewers outside of the US that churn out some really amazing projects, and this is certainly one of them.
Also note his receiver is a Collins designed R390A which is a 1950's design but kept in the government inventory for over 50 years as it had vacuum tubes and would survive an EMP often generated in a nuclear attack. A doomsday receiver!
So, you don't do tubes, then you could make this rig using about three transistors and a Color Burst crystal. For a pair of ears (receiver) think of the N2CQR/KK4DAS simple direct conversion receiver. Bummer! You would have to know CW.
Them that know can make things go.
73's
Pete N6QW