PRC-68 Series Repeater/Retransmission Cable
cable is wired as shown below:
A ---blk----- A (ground) (optional external power goround)
Ear) B ---blu----> D (mic)
C <---grn----F (FILL)
D <----org----B (ear)
Pwr) E ---red--- E (Ext Pwr) (optional external power + 12 to
F ----wht----> C (PTT)
This is a
cable so that whichever radio first hears a signal turns on the
(PTT) which acts as the transmitter.
needs to be done regarding the setting of the VOL control on both
be used as a transmitter in a repeater setup and probably any radio
needs to be done to see the effects of desense depending on
and frequency difference.
This needs to
wait until I make up a longer cable.
27 Jan 2001
- Retransmission/Repeater Cable - Used a 1N4744 15 Volt Zener
with the cathode band to red (pos supply) and in
a 1N4001 (RS276-1101A) with it's cathode end to black
1N4001 is there to raise the clamp voltage by about 0.6
This is to prevent the external supply from exceeding a little over
Volts. If it does the zener will conduct drawing a lot of
External Power Option
In the above
(Ext Pwr) E is wired to (Ext Pwr) E and that lead brought out for
power of both radios.
cable there is not much point, unless many radios were being done in
shop environment where batteries were not desirable.
cable it would make some sense to use the E to E wire for external
so that the repeater/retransmission system
could run for
a long time.
Connector with Strain Relief - the start of a set of cables
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