ANTENTOP- 02- 2003, # 003

Old computer's PSU

Old computer's PSU gives useful parts for antennas

Igor Grigorov, RK3ZK

Continue from ANTENTOP 01- 2003, #002

An autotransformer

AT-33T transformer works satisfactorily in connection shown in Fig. 1. It is an autotransformer connection. Mind, the secondary winding must be connected to the primary one at the right phase (A or B to C).

The experiment shows the right connection. Data for

the RF autotransformer are shown in Tab. 1- 3. Tab. 1 shows data for the RF autotransformer while this one is loaded to 300 Ohms. Tab. 2 shows data for the RF autotransformer while this one is loaded to 450 Ohms. Tab. 3 shows data for the RF autotransformer while this one is loaded to 600 Ohms. The autotransformer has rather big input resistance on ranges of 160 and 80 meters therefore values of a VSWR relative to 75 Ohms are shown in these tables.

An autotransformer

Table 1 RF- autotransformer loaded to 300 Ohms

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