ANTENTOP- 01- 2014 # 018

Converting Antenna Tuner MFJ-962D for Operation with Symmetrical Ladder Line

Viktor Drobot, RK3DL

For operation in the Air at all HF- Bands I use to antenna Delta. The antenna is fed by 300- Ohm Ladder Line. To match the antenna with my transceiver I use to ATU MFJ-962D. The ATU has symmetrical transformer at output. The transformer could provide good symmetrical operation... but with antennas that has low reactance. My Delta has significant reactance through amateur's bands. So the concept is not for me.

However it is very simple convert the tuner for operation with symmetrical antenna that has reactance. Figure 1 A shows simplified schematic of the ATU MFJ-962D. Figure 1 B shows converting ATU for operation with 300-Ohm ladder line that is fed antenna with significant reactance.

73! RK3DL

Figure 1

www.antentop.org

Page- 89