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LOC:JO51PL      CQ-Zone:14

My station,

onsists of a transceiver TS590S from Kenwood and the necessary accessories. I use Logger32 as logbook program and N1MM for Contests. Both Programs control the transceiver via a CAT interface. To transform the Impedance on the TWINCOM line, serves a 4: 1 balun followed by a 1: 1 balun.

If you click on current news from RBN, the setting of the current Frequency, based on the CAT interface, very fast and convenient

Transceiver TS590S

The impedances, at the transmitter end of the two-wire line, are in the range of 90 ohms up to 530 ohms. With the impedances above 150 ohms, the internal coupler is overwhelmed. The 4: 1 transformation brings the impedances to values the coupler can handle. For example, the impedance in the 40m band is 798 ohms (measured on wet ground). Divided by 4 results 133 ohms, so that the internal coupler is clear. The picture shows the conditions for 40m again.
Verluste 4:1
The Balun 4: 1 brings losses. The transmitter emits, in the example, 10W. By the Difference method, in the voltage measurement, one measures two voltages on the two-wire line, which is summarized as voltage U 2 , above the complex impedance. At the Two-wire line one calculates the active power P W on the real part of the complex Impedance R A to 7W. The losses are 30%, that is 3W. Dividing the 10W through 4, you get to 2.5W. So you would only at a quarter of the power at QSO partners will be weaker to hear an S level. The loss is not that significant. An LC coupler, without a 4: 1 balun, only lost 9%
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