I'm going to use ACC Pin #7 as Transmit Inhibit (High), and the manual
says this:
"TX INH (Transmit Inhibit Signal)
Pin 7 of the ACC connector can be configured as a
transmit inhibit input by setting CONFIG:TX INH
to LO=Inh (or HI=Inh). Holding pin 7 low (or
high) will then prevent transmit. An external 2.2 to
10 K pull-up resistor (to 5 VDC) is required.
If TX INH is set to OFF, pin 7 reverts to its
default output function, K3S ON (see above)."
This has confused me a bit... I'm not an electronic expert. The input
signal is 12 vdc, present all the time EXCEPT when the K3s keys up...
the amp gets that message and drops the signal to ) vdc... Not sure how
to pull off reducing the input from 12 to 5vdc with a single external
resistor.
I DO know how to do it with a voltage divider.... Vout = Vin x
R2/(R1+R2) Calculate resistor values, tie them together at one end and
that end connects to Pin #7 at K3s end. R1's other end ties to the (+)
signal in from amp, and R2's other end ties to the ground (conductor on
Pin #5).
Is there a simpler way to do this with a single resistor? Am I missing
something?
And am I in fact reading the manual correctly? The K3 expects a TTL
logic level + 5 vdc on Pin #7 to activate inhibit with TX Inh set to
"high"? A straight 12vdc exceeds the spec for that pin as an input?
(When it's used as the K3s ON output to XVERTER, it OUTPUTS +5 VDC)
I'm trying to get this custom cable built for this amp this weekend....
I'd appreciate a little help here. I don't want to let the smoke out of
anything....
73,
--
______________________
Clay Autery, KY5G
(318) 518-1389
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