EA3GCY EGV-40, Инструкция по сборке

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EGV-40 CW QRP Transceiver Page 22
This polyvaricon contains two variable tuning capacitors inside. With the external jumpers J1 A/B you
may select which section you will use; with the jumper in "B" you will use CV2, the larger capacitor, while
on "A" the smaller CV3 will be used.
CV2 has about 150 pF, CV3 only 70 pf.
In the back of the capacitor there are two padders (small trimmers) for a fine adjustment. The one in the
lower part
“X” (close to the terminals) goes in parallel with CV2, and the one on top “Z” is for CV3.
Adjusting these you may change the upper limit of the band coverage by some 10-15 kHz! You
will have to adjust the upper limit with the polyvaricon in its minimum capacity (turned all the way
clockwise). These adjustments will be carried out later on, in "ADJUSTMENTS AND CHECKS".
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IMPORTANT:
- If you want to wire the polyvaricon out of the board, please take notice that, when mounting it with
terminals up the connections get inverted and J1 A/B should be changed from J1B to J1A and vice
versa.
- When screwing the polyvaricon to the front panel (M2,5 x 5 screws) take care not to drive the screws
too much; they may block the internal mechanism of the polyvaricon. If needed, add one or more
washers avoid this kind of trouble
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L5 Tuning inductor of the VXO
A T68-2 is used (red toroid with an OD of 18 mm / 0.690 in).
Cut 102 cm (40 in) of 0.3 mm enameled wire and wind 48 turns on the T68-2. Leave pigtails of 10-15
mm (3/8-1/2 in).