Steve Rodgers wrote: "A couple of things to note here: Tying speaker audio to RXA is not the preferred method. RXA should be tied to the receiver's discriminator output, or to a point where the audio levels are less than a couple of volts peak. Pin 8 should be tied to DC ground. If that is the same as RF ground, that's fine. Microphone inputs tend to be very sensitive. You might need to add some attenuation resistors to the microphone input to knock the audio level from the card down so that you can easily adjust the level. If there is a line level input to your transmitter you'd be better off using that." Measuring the levels of the speaker audio, regardless of volume level on the radio, the voltage does not break 1.5v. Looking at the documentation for the card I felt that this was appropriate. I'm using regular Ground as of now. Grounding PTT with "Ground" and not "RF Ground" keys the radio as it should. So I'll just move my ground pin to there and leave PTT where it is. What I'm doing now is making a small circuit to work as COR. I can't seem to find a working version of the COR in the radio pin out, so I've taken a MOSFET and 5v battery to switch the level from 5v to ground when a signal is present and stay at 5v when no signal is present. Unless I'm blindly missing something to pull off the radio that will work the same way. Something like: +5v | 10k _ |--------------to PCI card
from radio-- |_ | | gnd
ASCII art may be butchered in the post though. The level from the radio should be enough to activate the FET and pull that output to ground, while allowing the 5v to pass to the card when there is no signal. Just for reference so you know where I'm coming from, I found a couple of Motorola HT600s on eBay with charger for pretty cheap and am playing with those since they seemed to have easy access to signals with the 13 pins on top. I thought this would be good to learn with while not investing tons of money in expensive radios to break. Thanks for the help while I struggle through this process. -JRH