630/160/80 & 40M QRP cw transmitter (also works on 30 meter cw)

Description

QRP homebrew cw transmitter, using a pair of 6V6 tubes and self-contained power supply. Covers all bands from 630 to 30 meters. 30 meters is possible by using the high end of the 40 meter coil, so I'll include a 30 meter crystal, though you may want to wind a coil with a little inductance for best efficiency on that band. The RF output tank circuit uses a Pi-network for harmonic suppression.
This transmitter has a transformer power supply for isolation, but it can still be very lethal if you don't handle it with the proper respect due for high voltage circuits. Besides the incoming 117vac, the key down rectified voltage for the plate and screen circuits is about 152 volts (about 185 no load). Everything is wired properly, but please don't purchase this item if you are not familiar with the dangers involved in working with exposed voltages inside the chassis.
RF output is about 5 watts, more or less, depending on the activity of the crystal used. This is very low power for the 630 meter band, so besides a specifically designed antenna system for this band you'll probably also need a linear amp if you want to transmit beyond your county line. That being said, the power out is quite ample for working the 160 thru 30 meter bands. I have a large base loading coil and a 25 ft. top loaded vertical which loads up nicely on 630m, with the feed point tapped up a few turns from ground. Operating below the am broadcast band can be a lot of fun, but it's a whole other world down there compared to the hf shortwave spectrum.
The listing includes everything in the photos, plus one crystal each for 630, 80, 40 and 30 meters. I don't have any spare crystals for 160 meters, but you can find them listed often on eBay. Loads very well on my 160m inverted L antenna, using the one 1822 khz crystal that I have on hand (again, not included). Four plug-in coils are included along with the crystals mentioned.
Working at the time of listing and I guarantee it will work if you get it hooked up properly to your antenna system. I will include a hand sketched schematic and locator diagram for the control functions, antenna, key jack, etc.
SHIPPING TO THE UNITED STATES ONLY.