Wow, unsolicited testimonial! Really, thank you so much Pat. Yeah, when other small transmitters were coming out, I'd joke with friends that the Radio Animal Grenade was 'the original, and the best'.. :)
I remember it, people were using heavy tube transmitters or expensive transceivers, and I don't think there was that much building or experimentation going on at the time either. I also think there was a perception that low power wouldn't work, when the standard was to use at least 25 watts on an AM signal.
I think it was just a mental block, because hams were always building QRP rigs that were getting out, but few pirates tried low power intentionally. A Grenade type of rig could have been built as far back as the 1970s, using CB finals that you could get at an electronics shop or by mail order for a few dollars. Radio Shack (RIP) carried one for a time in the 80s, C1909, to make an easy 5 watt AM transmitter with, driving with a 2222A, and a 2222 oscillator, modulating both the driver and final.
Toroids for the low pass filter were harder to get, but you could wind the inductors on half inch PVC water pipe. The inductances aren't that high to begin with, so it's not a hard job, you just have to calculate them out. The only less common part you'd have to order would be the crystal, or build a VFO from a red slug oscillator coil from a junk AM radio and one transistor. It's not bad for carrier current on the AM band at least.
Thanks again, it shows why it's good to experiment, and not let current thinking get in the way of your idea too much. Let loose and you never know what will happen.
Boomer