CDM1250 Pin 4 Constant Voltage

[tclark1320]

I have searched for a few days and have found many threads on the CDM radios regarding Pin 4 (external alarm output), but I cannot find the solution to my problem.

I am trying to use the CDM radio for a station alert system. In CPS I have programed the pin package to Public Address, active level low, and the external alarm configurator to Alarm Re-Arm. My problem is I am getting a constant voltage through pin 4 no matter if the external alarm is activated or not. The voltage I am getting is exactly what is being fed into the radio so 12v. Also I am using pin 7 as the ground.

[kb4mdz]

What condition are you using to activate Pin 4 to Low? Quick-Call? MDC?

And your Alarm Re-Arm may not be the right thing, I use Permanent External Alarm on my setups, for what that's worth.

Check your timing parameters on teh Accessory Configuration tab. Mine defaulted to Accessory Power Up Delay of 100 ms, Debounce Duration of 100 ms, and I set the External Alarm Duration to 10 seconds. External Alarm Delay is 0 seconds. I don't play with those timings much, except for the Alarm Duration, which is the time the pin should be at its changed state until returning to 'armed'

[tclark1320]

I am using Quick-call to activate the pin.

Also I have not changed any of the timing parameters. They are all default.

[jackhackett]

Are you measuring the voltage as it's being activated? I don't think the output latches, it just give you a pulse for the length of External Alarm Duration, if that's set to the default 1 second you could miss it. Pin 4 has a pull-up resistor to 12V and a darlington transistor to pull it low when activated.