QRP-40
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13
5. Insert and solder R1, the 10K tuning potentiometer.
6. Insert and solder S1, pushbutton switch.
Carefully select, insert and solder the following components in the order given
in the following steps. Check off each step as completed.
7. C16, 100 to 220 uf electrolytic. Electrolytic capacitors are polarized,
which means there is a right and a wrong way to install them! Generally,
the Negative ( - ) side is indicated on the capacitor, while the Positive ( + )
is shown on the PC board. Make sure that the capacitor is inserted
correctly into the PC board with the ( + ) lead into the ( + ) hole and the (- )
lead into the ( - ) hole.
8. R11, 100 ohm (brown-black-brown).
9. C19, .01 uf (marked .01 or 103 or 10 nf).
10. D2, 1N4148 diode. This diode is the small glass bead type. For correct
polarity, the dark band must face as shown on the parts layout diagram.
11. C10, .01 uf (marked .01 or 103 or 10 nf).
The preceding parts comprise much of the circuitry which blocks RF from the
receiver during transmission and permits the antenna to be connected to the
receiver jack during "key-up" conditions. To further complete this section of the
circuit, we now install the first of three 100 uh RF chokes. They look like
resistors with brown-black-brown-silver (or gold) bands.
12. Install L5, 100 uh inductor (brown-black-brown-silver).
13. Install R12, 1K resistor (brown-black-red).
14. Install R13, 1K resistor (brown-black-red).
15. Using a scrap component lead wire, install Jumper JMP1. Jumper
wires simply connect two PC board traces together, jumping over other
traces!
Next study the orientation of Q4, the keying transistor. Be careful in identifying
Q4. Q4 is the only PNP device, and its part number or case style may vary
slightly. If necessary, positively identify Q1, the 2N3904 oscillator transistor,
and set it aside for later, since Q4 is similar or identical in style. Proceed with
the following steps, in order, once you are positive you have selected Q4 as the
221-334 PNP transistor.
16. Install R15, 10K ohms (brown-black-orange).
17. Install C13, .01 uf (marked .01 or 103 or 10 nf).
18. Install R14, 10K ohms (brown-black-orange).
19. Install Q4, be sure to orient its flat side correctly as shown.
Summary of Contents for QRP40
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Page 11: ...QRP 40 11 QRP40 PARTS LAYOUT DIAGRAM...
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