Kenwood Tk-8180 and NX-3820 DTMF controlling.

[766keith]

I have headed up a venture to migrate a small police department to digital (NXDN specifically) while still operating with other agencies who are analogue on the same frequency. This has been quite the adventure as I had no knowledge of radio communications when this started 5 months ago. I have successfully made it happen though and gained a lot of knowledge along the way but I am far from being an expert. I need some advice but I need to explain the operation a little to preface my question. All other agencies in our county operate on one frequency and all others are still analogue. Someone told me previously that the FCC would not allow this but our licensing and buildout were both granted by the FCC. We established our own frequency pair and put up a repeater in the center of our city. A local radio shop built a crosspatch into the repeater using a TK-8180 in conjunction with an Arcom RC 210 controller. In our patrol vehicles we are operating the NX-3820. Both the analogue frequency and our digital frequency are operating in UHF. If we turn the 8180 at the repeater off, we are able to operate locally without the crosspatch to the other agencies and dispatch. Turn the 8180 back and and we are connected to the analogue system again. The problem we have now is that when we talk on our local digital frequency, we are limited to whatever channel the 8180 connected to the repeater is on. If we needed to switch frequencies to talk to say the fire dept or EMS frequency, someone would have to drive to the repeater site and turn that 8180 to that channel to make that connection. I want to use autodialing with DTMF tones to be able to turn the channel on that base radio. From what I am seeing this is very simply done in the 8180 which is what we also previously had in our cars but of course are not digital capable. I am not seeing anything about the 3820 having this same capability to send the DTMF tone back to that older 8180 to turn the channel. Am I missing something? I am sure Kenwood would not revert backwards and take that technology away in a newer more advanced radio. They also sell the keypad mic as an accessory for the 3820 and I cant think of another application for these mics if these radios are not capable.

 

[DeoVindice]

I haven't worked with NX radios, but I've accomplished this with Viking equipment. Create a system utilizing DTMF PTT-ID, set the radio ID to the repeater control code, and create a channel using said DTMF PTT-ID. The user selects and keys up on this channel for repeater control. There's probably a better way to do it though.

 

[mmckenna]

The NX-3820 will absolutely do DTMF auto dialing over NXDN.

You need to set up your Autodial list under the DTMF tab.
You need to set up a button to access your DTMF audio dial list.

There's other settings, but that should get you started in the right direction.


Any reason why you don't just add the EMS and Fire channels into each individual radio, that way officers can just select what they want without having to send DTMF?

 

[DeoVindice]

The NX-3820 will absolutely do DTMF auto dialing over NXDN.

You need to set up your Autodial list under the DTMF tab.
You need to set up a button to access your DTMF audio dial list.

There's other settings, but that should get you started in the right direction.


Any reason why you don't just add the EMS and Fire channels into each individual radio, that way officers can just select what they want without having to send DTMF?

Much more elegant.

 

[766keith]

The NX-3820 will absolutely do DTMF auto dialing over NXDN.

You need to set up your Autodial list under the DTMF tab.
You need to set up a button to access your DTMF audio dial list.

There's other settings, but that should get you started in the right direction.


Any reason why you don't just add the EMS and Fire channels into each individual radio, that way officers can just select what they want without having to send DTMF?

Thank you!! All agencies in our county operate in analogue. The reason we had to set up the system we did is because we do not own any of the equipment or frequencies they operate on. We had terrible reception with their repeater sites. our new repeater works flawlessly to get us in contact with their repeater. The county owns all repeater sites be in Sheriff, Fire, EMS or rescue. We in theory could program the analogue frequencies into the radios as they will do analogue or digital but we would have the same horrible connection we put the system in to get away from. While we primarily operate on the Sheriff's Channel, it would be nice to have the same connectivity we have now with the digital system across all channels.

 

[mmckenna]

I'd still program them in, just so you have an option.

If you have a full time dispatcher, it's pretty easy to have them set up a patch through the console. If you don't have a full time dispatcher, then your solution may be the logical option.

Using DTMF to steer the system should be an easy solution. I was working on an NX-3920 earlier this afternoon, and while we don't use DTMF, I did take a quick look at the settings. Should be fairly easy to do. There are some function programming guides for that radio that may help. If you want to PM me your e-mail address, I can drop box one to you.

 

[766keith]

I'd still program them in, just so you have an option.

If you have a full time dispatcher, it's pretty easy to have them set up a patch through the console. If you don't have a full time dispatcher, then your solution may be the logical option.

Using DTMF to steer the system should be an easy solution. I was working on an NX-3920 earlier this afternoon, and while we don't use DTMF, I did take a quick look at the settings. Should be fairly easy to do. There are some function programming guides for that radio that may help. If you want to PM me your e-mail address, I can drop box one to you.

I will do that now. Thank you for your help!!