This is the collection of parts I hope to turn into a linear amplifier, based on the 65 year old RCA 811A tube design. My collection of parts so far is shown below! Anybody have a good circuit diagram??
The plan is to use 4 of these, in a push-pull arrangement, for about 800 watts output in class AB2
The transformer provides 1500v AC at 500 ma, along with 16 amps of 6.3vac for the tube filaments. In addition, it provides 12 volts ac that can be rectified into DC to support relays, meter lamps etc.
Here is a swap meet find - a full wave bridge rectifier capable of handling a couple thousand volts.
The transformer requires 55 MFD of capacitance to deliver its rated voltage / amperage with acceptable ripple. To achieve this, I will use these 4 240mfd 450v capacitors in series to provide 60mfd rated at 1800 volts. Don't touch these babies unless you know their discharged!
You only need one of these, but I found 2 in the size range needed for the plate capacitor. These provide between 40 and 450 mfd. Again, these are swap meet finds and are in great condition.
Here are 2 coils I found, both are wound at 6 turns per inch, the top coil is 10" long and 2.5" in diameter, the shorter coil is 3" in diameter, and has been tapped at every other turn. You guessed it - swap meet finds.
Here is the nice way to go, a variable inductor for vary exact tuning of the output tank circuit. This was a gift, but as you can probably guess, it was found at a swap meet!
So, there is a peek at my amplifier parts box - parts still to be located are filament chokes, plate chokes, meters, fans, switches and most of all - a cabinet!
Keep watching as the project progresses!
73's, see you on the air (if the signal is loud, it's probably not me!)
de K7ZS aka Kevin