Low Current Kinda High Voltage QRP Tube Transmitters

I just saw a heartening post with respect to the gang's and my quest to see if Agent Sonya could have built her own radio rig.

Pete, one of the presenters on Soldersmoke even mentions W1REX in the post in conjunctions with this transmitter schematic:

Rex is better known in these parts as the ham that produces RockMite and Tuna Topper kits that populate the innards of Project TouCans.

Getting back to Agent Sonya, and also to safety, I was heartened to see Pete mention a supply that had occurred to me for plate voltage and current: nine-volt transistor batteries. Gone forever, apparently, are the B cells of yore, but we can definitely string together 9 volt cells. I wandered if there were issues with this type of supply I'd missed. There aren't!

The post and the circuit above also answered a question I'd often wondered about with respect to keying tube circuites. That MPSA92 looks pretty hefty what with its 300 volt rating. It is and it isn't. the maximum current draw is half an amp. The packaging is also 'normal' for what someone would expect to find on a modern circuit board.

It all looks so simple. Now, I just need time. Stay tuned.

Thanks Pete and Rex!

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