Ramsey Electronics FX-440 Manual page 119

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[ ) [ ) H42d. Join, solder and trim the 5 RECV diodes so that
all six anode wires are neatly connected to the RECV bus-wire
"bridge" installed in Step H23.
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[ ) [ ) H42e. Solder all 6 RECV line diode cathodes on the solder-side
of the PC board. Trim excess wires.
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We have reached the mountain-top in building the RECEIVE section of
your transceiver as well as many sections or stages needed for
transceiving. Double-check your work as needed.
Frequency Programming and Channel Switch Preparation
Before completing the transmit functions of this VHF FM transceiver, we
should now verify that the PLL Frequency Synthesizer gives performance
as desired and as designed. Regardless of whether you pursued the
VCO/receiving tests proposed as optional in the previous section, it is
NOW time to put your completed receiver section through its paces.
In order to do this, one or more receiving frequencies must be
programmed on the primary matrix. If you already have a firm plan for
how you wish to program some or all of the channel positions, you can
proceed with making the frequency programming lines that you are sure
about. If you have little or no sure idea of how you want to set up the
channel selector switch, you can build up a simple switching system that
will let you try any frequency of your choice.
If you are unsure of what frequencies to program, we suggest the
following to get started:
Channel 1: 446.00 MHz Simplex (national calling frequency)
Channel 2: One additional simplex frequency such as 446.1
O
MHz
Channel 3: Main repeater of your local radio club
Channel 4: One additional repeater in your area
Channel 12: A popular packet frequency in your area such as 441.00 or
441.25 MHz
Add more channels as you become more familiar with 440 MHz band
operation in your area You can change or delete any of these
frequencies whenever you wish.
[ ) [ ) H44a Construct at least two diode bridges for
frequency programming as illustrated below.
FX-440
Assm. 59