Small Wonder Labs SW-20+
Click for larger view
This is my 20 meter QRP CW transceiver.  It consists of a Small Wonder Labs SW-20+ kit mounted inside an old CB case.  I repainted the two halves of the case with black textured Rustoleum spay paint used for patio furniture, and made a front panel out of some scrap ABS plastic I had laying around.  I painted the front panel white and used rub-on lettering for the control labels.  I then sprayed clear spray paint over the lettering to keep it from rubbing off.  For the frequency dial I used a CB channel knob.  I removed the channel numbers and used the rub-on lettering for the frequency readout.  I used my Kenwood HF rig as a guide to find the right spots to put the numbers.  I then sprayed clear spray paint over the clear plastic disk and then reattached it to the knob. 
Internal view, click on photo for a larger view.
This was my first effort in building a QRP rig, and I'm very pleased with the result.  The radio covers 14.023 to 14.0575 MHZ.  At first, I was getting about three watts output, but I turned it back to two watts since I didn't want to take a risk of burning out the final transistor.  Power consumption is 78 mA on receive and 425 mA on transmit, so you can run this rig from just about any 12V power source.  I use either a 12V power pack used to jump start vehicles or a modified computer power supply.

I added a modification in the form of a power and a transmit LED.  I got the two LED's out of an old junk CB.  The power (green) LED is connected to the radio side of the on/off switch, and the TX (red) LED is connected to the collecter leg of Q3, the keying switch transistor.  A current-limiting resistor was used for each LED to connect them to ground.  The antenna and external speaker jacks were left in the CB case.  A 1/4" jack was added for the CW key, and a coaxial power jack was installed where the power cable originally passed through the case.  I added a stereo headphone jack in the front panel, and used the external speaker jack as a mono headphone jack.

The Small Wonder Labs kits are excellent kits and I highly recommend them.  I've made quite a few contacts with mine and have enjoyed getting into the world of QRP with it.

I have since disassembled this radio and included the PC board in the MultiWonder QRP radio, which combines the SW20, SW30, and SW40 boards into one radio.
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