Batboard

Friends,

I return with hat in hand again. The same VHF MSF I was asking about changing from a CXB to CLB is staying a CXB. I have new questions about other features of this station. I was surprised to learn that the power supply for the PA is 28 VDC. Did Motorola ever make a supply that allowed for battery backup for these VHF stations?

I am also having problems interfacing a LinkComm controller to the MARTI port. I have enabled the MARTI in RSS and set the station for full duplex with no in-cabinet repeat. I see Pin 11 changing state with carrier and proper PL, but when we hook up the PTT from the controller to Pin 5, Pin 11 behaves very strangely with receive signal. I have been told the MARTI port is all high impedance, but this just doesn't seem right.

I'm sure I'll be looking in the mirror to find the source of the troubles but could any of you tell me where the mirror is?

Regards,

Paul

Skip the MRTI connector and save yourself some time.

Motorola designed that station to be easy to interface. Assuming that your CXB station is equipped with TTRC [wireline control] and has current firmware, everything you need is built right in.

You simply program the MSF as a duplex base station [i.e. no internal repeat]. You program whatever receiver qualifiers you want [PL tone, etc.] and whatever transmit PL you want.

There is one user input and one user output on the station option connector. Program them so that you have receiver activity indication as the output and line PTT as the input. Then all you have to do to interface the Link controller is connect those signals plus ground and the 600 ohm wireline receive and transmit audio.

Yes, they did make a battery revert PS for both the 28 and 12 volt portion of the high power VHF station.

You can easily add battery backup to this unit with one of the many 24/28 VDC transfer switches and a Duracomm smart charger to maintain the batteries. Never use the built-in resistor type charger that's found in some transfer switches as these cannot regulate or control the charge and will gas the batteries over time.

Two yellow-top Optimas in series work great for this and they arent alot of $$$. There are some that claim these batteries are NFG for backup, but I will totally disagree since I have quite a few out there with 5+ years on them and they are still strong...and they don't cost $400 each like most of the so-called "site" batteries do.