Harris XG25M & Avtec

[wstorrs]

Good morning,

I work for an ambulance agency located in Ontario County, NY. We utilize a VOIP radio system (AVTEC) which is now owned by Motorola.

We operate on the County P25 - Phase I Trunked system which operates pretty well. Due to our extensive coverage area, we use the AVTEC system for our Communications Center.

Over the past 6 months, we have been having issues with a Harris XG-25M which is for our P25 system for our local channel which is what we utilize to dispatch our agency.

We purchased a new XG25M, no both radios have been sent to Harris twice for repair. They just overhaul the main board and send it back to us.

We have had our tower inspected both physically climbed, and wires checked. There’s been various testing completed with shows everything is well within operating limits.

A few weeks ago, I had the Harris that recently came back from Harris from repair, and it was working “okay” not the best, but out of the blue the radio stopped working and shut off and would not turn back on. Radio has returned and now getting re-programmed again.

I am just looking for ideas on what could be causing this. We have been through several radio vendors and technicians who have all set everything is working perfectly fine. It has been extremely frustrating to say the least!

Any input would greatly help me!

 

[prcguy]

What exactly is the complaint? What specifically is not working? What is being repaired or replaced in the radio when you send it in?

 

[merlin]

First thing I would check is the power supply. The radio should retain its programming through a shutdown.

 

[wstorrs]

The issue is that each time I place this radio back onto the rack, make the connection to the Avtec outpost within a few weeks, it slowly degrades in operation and eventually becomes a non-working piece of equipment. I am looking for some thoughts on what could cause this issue. It has been incredibly frustrating. Harris only relates they replace the main board and send it back to me. They don't do any additional diagnosis.

The radio complaint would be that eventually RX transmissions become scratchy then it will either shut off completely or not be able to TX or RX. Two different radios -- same model.

 

[prcguy]

Looking at the XG series 44 pin connector I see the discriminator output has a DC bias on it and you need a coupling capacitor of at least 33uf in series. I also see the ground pins for audio are fused and there are specific grounds for audio, GPS and other signals, so if someone directly connected a transformer input device to the audio output lines on a Harris XG you will have problems.

Do you know how the radio is connected to the AVTEC and if it has a series capacitor or something to protect from DC on the audio lines?

BTW you may run into similar problems and need similar fixes if connecting a Motorola depending on model.