Harry's TX

This is PA0LQ's 136 TX using four parallel PL519s in the PA with 520V HT at 800mA for 300W output. The tank circuit has 30,000pF of mica Cs to tune it, plus a bendable loop for fine adjustment. The VFO at 2750kHz is divided by 20 and fed to the valves via a BD135/BD136 driver stage.


This is PA0LQ's loading coil for LF. Harry's QTH is on the 12th floor of a block of flats and his antenna (35m of wire) is lowered from the balcony at the end of a 4m fibreglass pole. This 4mH laundry basket coil is sited on the balcony during operation.


Fine tuning of the PA0LQ antenna system is done with this variometer wound on some bins retrieved from the waste skip of a Chinese restaurant! It has a range of 200 to 600uH.