General description

JUMA-TX1 is a CW transmitter for 80 m and 40 m amateur radio bands. It is a follow-up project to the JUMA-RX1 HF receiver. The VFO is using DDS and the output power is 5 watts. JUMA-TX1 is a compact stand-alone QRP transmitter with good CW keying primarily intended for use with the JUMA-RX1. Additionally it can be used with any HF receiver which covers the 80 m and 40 m amateur radio bands. The frequency stability is excellent and the frequency can be set in steps of 10 Hz, 100 Hz, 1 kHz and 100 kHz.

JUMA-TX1 transmitter is built using the same small size aluminum enclosure as the preceding JUMA-RX1.

The TX1 consist of two circuit boards, the DDS board and the TX-main board. Additionally there is a LCD module for frequency, relative power and supply voltage display. No coil winding is needed when constructing this TX.

The antenna connector, power supply connector, power switch, key connector and the RX antenna connector are on the rear panel.