MaxTrac Arduino brain transplant?

[bbrasmussen]

bbrasmussen,

I need to know more about the UT program. I have the maxtrac with ardunio installed. It works , but in UT when I put in a control freq it parks on that one and I receive it perfectly but only that 1 control channel. I have about 6 control channels I want to scan through. Also why do you need the second maxtrac? I pick up both sides of the conversation on one maxtrac? Can you run two usb ardunio's at the same time? In UT? Please help.

So when I am controlling my voice-following Maxtrac via UniTrunker, I hear only the audio from active talkgroups that I have selected to listen to. When it is parked, it's on a frequency with no carrier, so the squelch of the Maxtrac silences the audio until UniTrunker tunes away from the parked frequency to another call on an active frequency. As far as scanning control channels, I'm not sure UniTrunker can control the radio to do that.

However, a second Maxtrac, as I have in my setup, could help you scan the 6 control channels. My second Maxtrac is sometimes hooked up to UniTrunker as a second voice radio so I can hear 2 calls simultaneously. I can also run the second radio independently from UT and just set it to a control channel and use that as my discriminator audio source for UT. I can set it up so I can toggle through a programmed list of control channels for different trunked radio systems in the area.

In your case you could use a second Maxtrac similarly for scanning discriminator audio. Just program the 6 frequencies into the arduino and set it to scan those frequencies if the squelch is closed and to hold a channel if the squelch is open.

 

[michaelsbus]

c_rock, the whole concept of the project is that one radio is used to receive the cc data, which gets sent to the PC to be decoded by Unitrunker. Once there's a hit on something you want to hear, the freq of the voice channel is sent to the arduino board, which sends the data to the 2nd radio to set the recieve freq. The guy used 2 maxtracs because they are cheap and easy to get, but any radio can be used to receive the cc data; the arduino interface is strictly for the maxtrac to recieve the audio.
It's too bad I discovered this thread a year after the fact. I noticed a couple of things:
If R=0901 to set the divider for 12.5KHz, then setting it to 1201 should set the divider for 6.25KHz
Then the radio can be programmed for the 6.25KHz splinters with ease.
Unless, of course, that the low-order bit does indeed determine N/A versus R loading, or is it the sequence of the bytes sent? If you reverse the sequence sent to the radio, and it doesn't go all fubar, you got yourself a 6.25KHz radio!
You might also send 0900 for the R value and see if that works.
Would seem to make sense as future support for NFM. After all, the N/A value steps by 4 for 25KHz...

Another note: I may be out of touch on the matter, but I thought that IDEN was a proprietary vocoder. Unless someone has broken the code, but just can't figure out the cc structure!
But then I also thought that the whole Nextel thing was a compendium of old paging and other transmitters that they cobbled together into a "network," not much like the structure of cellular or trunking systems....

 

[Batman_]

Astro Spectra...?

See - right there you just essentially said "I could care less, however *IF* this worked for P25 THEN I'd be really interested"

There are already off-board plans and discussions to port this to an Astro Spectra, where, if and when successful, you get your P25. And that's besides the wide open possibilities of opening up previously unscannable protocols such as iDen. I just hope that this ends up being well documented, unlike similar explorations in the past.

Any pointers where to look "off-board" for the Astro-Spectra project??
This thread is now a year later, and progress must have been made ?

 

[Batman_]

Send
BIT,1
to turn the ASCII bitstream on, and
BIT,0
to turn the ASCII bitstream off.

The Parking (mute) frequency is now 0.0000
Select "BC346XT" in UniTrunker to control it.
It's very fast to tune, about 10ms.

What does the "bitstream" option do? Is that something UniTrunker uses?

I want to use TRUNKER with this, is anyone else doing this??

 

[hydrolocked]

Has this just hit a dead end?

I'm thinking that this type of project would be phenomenal for a low band maxtrac I picked up - this would be a way to no longer need a Dos based computer....

since the radio will live in my shack, i could put a controller on it and use the PC as a control source to select frequency... or add a control set to the arduino....

 

[mrsvensven]

At the time of this thread, I did have a working "maxtroller". An arduino took RS232 data from unitrunker running on my computer and output the tuning commands to the maxtrac. You could also manually tune the maxtrac by sending the RS232 commands from a terminal program on the computer. I have not used it lately so I don't remember exactly the procedure to build it, but I followed the directions and used the code from this thread.

This was only controlling the frequency, not PL. You may also need to resend the tune command to the radio every time it is power cycled. A DOS computer is easy enough to use that this is probably more trouble than it is worth unless you are changing channels quite often.