Check the listing for details. SCHEMATIC ONLY 80/40/30 METER CW QRP BATTERY POWERED HAM RADIO TRANSMITTER. Condition: Used. Listed at 14.00 USD. This listing is for schematic ONLY to build this transmitter. No parts, manuals or instructions of any kind are provided, just a complete, hand sketched schematic, showing all parts values. Construction is fairly straightforward, but this is a project for those having previous hands on experience in working with the construction of electronic circuits. Once in operation this circuit has exposed high voltage! If you are not experienced in working around lethal voltage, then I do not recommend that you purchase this item. The circuit employs a battery powered dc to ac inverter, and the no load dc voltage is about 250 volts rectified dc (about 185 volts key down). So even though the power source comes from harmless 9 volt batteries it can still be lethal if not handled responsibly. So this circuit is for a self-contained vacuum tube ham radio QRP 6G6G cw transmitter. With fresh batteries I get about 2.2 watts output on 80 meter cw. It uses plug-in micro-inductors for the Pi-network plate circuit, which, in the circuit that I built, I installed the inductors in a crystal holder, as shown in the photos. The dc power converter, using the 3 nine volt Li-on rechargeable batteries, will run for about 2 hours before needing to be recharged. I've been using 600 maH batteries, but have noticed online that the 9 volt rechargeable Lithium batteries are now available in 1000 maH versions. So with 3 of those installed you'd likely get close to 3 hours of operation before needing a recharge. The dc inverter circuit employs a pair of TIP41C power transistors, working with a common 6.3 volt (117v primary) transformer. The output is then rectified by a 1N4007 diode, then filtered. In the photos you will see 2N3055 transistors, but they are bulky, and after making several of these inverters for different transmitters, I've switched to using the smaller TIP41C 6 amp transistors. When powered on, in transmit mode, this circuit requires about 1.5 to 2.0 amps to run. Under no circumstances should you apply any more than 8 to 9 volts dc. I've even used a common 9 volt wal-wart transformer to power this transmitter, but those things typically employ some sort of a switching/sawtooth circuit which produces a noticeable rasp on the cw tone. The inverter uses a little 6.3 volt filament transformer with a turns ratio of about 18.5 to 1. This means that increasing the voltage by one or two volts could potentially blow the power supply! So keep it to 9 volts max and you'll be fine. The 9 volt Lithium-ion batteries typically provide about 8.2 to 8.4 volts, fully charged. This little rig that I built loads up nicely on 80, 40 and 30 meters. In my experience I have very little issues with chirp when using the 49/U QRP crystals. I sometimes get a hint of chirp on 30 meters but can usually tune it out by careful adjustment of the plate input capacitor to the Pi-network tank circuit. No 49/U type crystals are available for 30 meters, so I used a 49/s crystal for that band, which can be a bit more prone to chirp because of the lower power capability, as compared to the 49/U. This is a fun project to build and use! MAILING TO THE UNITED STATES ONLY