First we start with the rf side of things:
Q1=2N2222, 2N3053, etc. be sure to heat sink
27 ohm resistor should be rated for 2 watts or better
TANK COIL: use a 1.25" diameter form (35mm film canister, pill bottle, etc.) and #20 - #22 AWG enameled ("magnet") wire. To make tap, wind L1 to the "tapped at" number of turns (see table below). Make a loop about 1 inch long, twist it a few times and finish winding. Sand the insulation off the end of the loop. This is your tap. After winding L1, wrap it with a thin layer of masking tape and wind L2 on top of the tape in the same direction as L1. Secure L2 with more tape and finish by sanding insulation off remaining leads.
L1: L2: (primary/collector windings) (secondary/antenna windings) 1.8 Mhz--60 turns, tapped at 20 1.8 Mhz-- 8 turns 3.5 Mhz--45 turns, tapped at 15 3.5 Mhz---6 turns 7.0 Mhz--21 turns, tapped at 7 7.0 Mhz---4 turns 10 Mhz---15 turns, tapped at 6 10 Mhz----4 turns
Now we deal with the audio side of things:
C1 10uF 16V electrolytic C2 220uF 16V electrolytic U1 LM386 amplifier VR1 potentiometer 5k or greater
The Jolly Roger will produce a 500 mw am signal, simply tune the variable capacitor in the transmitter circuit for best output and adjust the pot in the modulator circuit for best audio. Because this is a modulated oscillator based transmitter there may be a bit of frequency modulation along with amplitude modulation causing the signal to sound distorted when listening in ssb mode but the audio should be clear in am mode. The Jolly Roger is possibly the simplest am shortwave transmitter you'll ever see, all parts (with the exception of the variable capacitor and crystal) can be found at radioshack, variable capacitors may be salvaged from most any cheap am/fm radio.