Five rings were inserted on to copper tube in ¼
inch OD. At one side a jumper connected the tubes. At the other
side a wire was soldered to the tubes. It was winding for coaxial
cable, 50- Ohm. Three turns of insulated wire (300- V, 20- AWG)
were inserted inside of the copper tubes. It was second winding, 450- Ohm intended for Beverage Antenna. The transformer
was covered by wide shrink that after thermal heating hold the
rings.
Ready
transformer was tested with small ¼- Wtt
resistor on 450-Ohm. Table 5 shows data measured by MFJ-
259B. MFJ- 259B does not indicates the character
of the reactance (capacitance or inductive) so I used sign @ at
the reactance. It looks like the transformer was not optimal for
the 160- meter band. Though I decided try it. After 5 minutes
I have the transformer changed. I straight away did measurement
of the Beverage
Antenna with Transformer with Insulated
Windings. Table 6 shows data for Beverage Antenna with Transformer
with Insulated Windings measured by MFJ- 259B. MFJ- 259B does not indicates the character of the reactance (capacitance
or inductive) so I used sign @ at the reactance. Table
7 shows data for Beverage Antenna with Transformer with
Insulated Windings measured by IC- 718.
SWR of the Beverage Antenna with
the new transformer was
good. For my opinion level
of the electrical noise went down at all bands. The transformer
with Insulated Windings worked well. Evening came to me and I
turned on to the Test. The load worked the last part of CQ- WW-
160- Meter Contest without burning. After Contest I visually checked
the termination load. It looked like new. During the test I made
124 QSO, 33- US States and 3 Canadian Provinces. Not bad.
So it is possible use at Beverage Antenna termination
load made on the base of wire wound resistors. It was a little
surprisingly for me.
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