One-valve QRP CW Transmitter
by Raimo Jarvi OH8MNM, Finland

Raimo's crystal-controlled QRP one tube CW transmitter is based on my 80m CW TX, but he uses a PCL86 valve with some slightly different component values and a different tank coil to mine. The circuit diagram is shown below. This TX gives up to 6W output but Raimo prefers to use 1 - 3W QRP power. The transmitter also works Ok on 40m.

Photographs

The following pictures show Raimo's transmitter at various stages of construction.

Testing on an old chassis Full size, 859 x 683, 116K Another view of the test rig Full size, 791 x 609, 90K Building the new chassis Full size, 751 x 571, 62K View from one side... Full size, 1024 x 768, 184K ...and from the other side Full size, 1024 x 768, 184K Underneath the chassis Full size, 725 x 571, 93K View from behind Full size, 635 x 525, 73K Front panel Full size, 669 x 457, 184K The TX on top of Trio Receiver Full size, 1024 x 768, 175K