Batboard

The organization I work for uses Zetron Model 45 phone patches connected to conventional Quantar stations via the patch port on a DIU3000. The DIU converts the digital keypresses to DTMF and sends them to the Model 45 as analog audio at the patch port.

At this point all of our portables/mobiles are Motorola XTS/XTL series.

What other equipment (non-Motorola) is capable of generating the "digital DTMF" used in P25 mode? This is probably an odd place to ask this question but I can't think of a better place. Most often when I ask this question I just get dumb looks.

Also, is anybody aware of any device other than the DIU3000 that will decode this data? Since the DIU3000 is discontinued, I am wondering if it will even be possible to do a phone patch in P25 mode.It seems "nobody" does phone patch anymore. It is a nice trick to have when cell phones stop working or you're in an area that has no coverage. But that never happens, right?


Thanks,
Randy

The newer EF Johnson 5100 portables with the newer firmware should be able to send the digital DTMF packets. Unfortunately, I don't know which versions are required. The newer 5300 mobiles might do it, too.

I seem to remember Midland's P25 radios offering some P25 digital DTMF capability, maybe even including decoding of the packets, but I could be wrong on this one. You might check them out, though...

I think that's about it for the P25 digital DTMF packets. Most other manufacturers don't support it, which is too bad, since DTMF can be used for a lot more than telephone interconnect.

FYI, P25 subscriber set specs usually will indicate if P25 Unacknowledged Data 12 packet encoding is supported. The problem is that sometimes this P25 capability is only narrowly supported, so it may only involve pre-stored strings of data 12 packets. It may or may not support the individual manual transmission of one-by-one characters, which is normally required once the Zetron World Patch 35 autopatch is connected via the DIU3000 to the PSTN. To my knowledge, only Motorola subscriber gear supports both pre-stored Data 12 steams of characters (such as to bring up or down the autopatch connected to the DIU3000), as well as support transmission of individual characters, so you can then dial numbers on the fly.

IMHO, I don't think this is worth fighting, given that the price of Motorola P25 radios is virtually the same as other vendors' P25 gear.

We use a device for some basic remote control from Broadcast Tools.

http://broadcasttools.com/view_product.php?pid=115