Ramsey Electronics SR-1 Instruction Manual page 11

4-10 mhz shortwave radio
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range.
17. Install L2, the oscillator coil.
18. Install D1, the varactor diode, which looks just like a transistor but
with only two leads, making sure that the flat side is oriented correctly.
19. Install R5, 270 ohm (red-purple-brown)
20. Install R2, 10K potentiometer tuning control.
21. Install C6, 10 µF. electrolytic below R2.
22. Install R3, 10K potentiometer volume control.
23. Install C9, .01 µF (marked .01, 103 or 10nF).
PROGRESS SUMMARY
In addition to becoming familiar with the PC board and installing a
respectable number of parts, you've made TWO accomplishments worth
noting. First, you have modified L1 and L2 as needed. Second, if you'll peek
at the left "third" of the schematic diagram, following from the antenna to C7,
you already have built a "direct conversion" shortwave receiver capable of
CW-SSB reception throughout the SR-1's tuning range. If you want to prove
it to yourself, connect an antenna, 9 volts DC to Jumper 1, and a high-gain
test amplifier to C7. You will hear plenty of CW-
RTTY shortwave signals as well as the "carrier"
signals of the AM broadcast signals which this
SR-1 superhet receiver is designed to detect
and amplify. .
24 Locate the two green 1800 µH
inductors (marked 182J). These inductors
will be placed in the position marked for L3.
Follow the diagram at right for proper
placement of the inductors.
10 pF capacitor on back of board
Inductor leads go here
Inductor leads go here
25. Flip the circuit board over
and install a 10 pF capacitor on
the bottom side of the board
between the two inductors
installed in step 24. (see below for
placement)

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