"Dave S" wrote in message
nk.net...
I want to ask the group, particularly the avionics guys in the group,
regarding installation of the King KX 175 and KY 195 radios.

I have the applicable pinouts loaded to my EAA chapter's website
http://www.eaa12.org/images/175-195outs.pdf for quick reference

I am using Jim Weirs Audio Panel/Intercom model 564/5 but that is likely
not a major factor in the questions

Item 1)

On the com side of things, there are aux audio 1-4 listed, (on pins 36,
37, 15 and 16). I am presuming these are audio OUTPUTS, want to verify
that (seems intuitive but I am not assuming ANYTHING). A notation on the
pinouts page indicates that "auxiliary audio #2" (pin 37) is intercom mic
input for these models. That conflicts with the presumption that i WANT to
make regarding these aux audios.

The Aux Audio pins are INPUT pins for those too cheap to buy an audio panel
yet want multiple inputs to a single phones/speaker output.



Jim's intercom/audio panel has two audio inputs from the respective radios
(phone in and speaker in, I am presuming speaker in doesnt have sidetone)

That is correct.


Given this, I want to confirm on the 175 (or 195) com portion, that pin 41
"Speaker output" goes to the intercom "com# speaker input"

That is correct.



and then
also confirm or determine if its Pin 37 "aux audio 2" that goes to the
intercom "com# phones in" (presumably with sidetone) If not, what is the
purpose of the aux audios?

No, the headphone output goes to the phones input on the audio panel



Item 2)
Pin 34 is a COMM 500 Ohm output. What exactly is this used for? Is THIS
the headset output to the intercom?

That is correct. That is the headphone output of this particular radio.




Item 3)
Confirming that pins 17 and 18 remain bridged in 14V operation, and that a
transformer is inserted between 17 and 18 for 28V operation.

I have absolutely no idea other than to say that a transformer is never used
in a DC application.



Item 4)
In the vicinity of pins 21,39 and 40, there is a dashed rectangle on the
schematic that appears tied to the speaker return and power ground, but
the dashed area crosses over/under/around the mike audio and key "lines"
on the schematic. Can someone clarify exactly what that dashed box
signifies?

That signifies that all the wires contained within the dashed line are
shielded wires tied to the power ground.


Jim