Tinkering

Well, been stuck in the house in rainy Ohio. Every time there is a dry half-day, I have to mow. I did get Emo to the Bark Park yesterday.

I have a bunch of old ball game radio broadcasts from the 40's and 50's on my computer, and I am trying to home brew an AM transmitter so I can listen to them on one of my old tube radios. There are many circuits for this on the internet, but I wanted to design my own for kicks.I've come a long way for two days, using my very deep junk box - or junk room. I'm seeing modulation on 641 kHz with a 12V supply. Here's the circuit:

Here's my breadboard mess:

But, I'm getting close. I can see a nice sine wave, and the modulation seen below. I can hear the 400 Hz signal from my old frequency generator in my Kenwood R1000 receiver!

I need to get more modulation, then the critical part of putting together a permanent circuit on a circuit card and tweaking things. It's been fun so far. BTW, I'm using the first audio transformer that came to hand, a Mouser TM108. I think I need a step-up transformer.