Here's a fun trick

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AZScanner

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Some PD action in the nearby vicinity of my apartment complex the other day provided a unique opportunity to try an experiment that I thought I'd share:

First a little background. I have an old BC250D scanner that I don't use much because my area uses 9600 baud trunking, not the 3600 baud that the BC250D can track. Now, I have a BC796 which CAN track 9600 baud CC's, but there's something funky about the Phoenix system and the decode on my 796 is sort of hit or miss. There have been times when the scanner just flat out refused to switch to the appropriate frequency, even when locked on a particular talkgroup. Very frustrating, especially when there's something going on right down the street and I want to keep up with the action.

So, I came up with an idea - a sort of "close call" for this scanner and it worked GREAT, even better than the 796! Here it is:

First, I made note of all the frequencies in use on PRWN Simulcast A, which is where the PD comm's for my area reside. I then subtracted 45 MHz from them, resulting in a list of mobile inputs. I programmed them in frequency order from lowest to highest as conventional frequencies.

Next, I initiated the scan on that bank and waited. Sure enough, I was close enough to snag the input comm's, although that decode was hit or miss due to the fact that you have to be pretty close for those frequencies to work, obviously. Now, here's the trick - whenever the scanner paused on any activity I pressed the REVERSE button and the scanner switched over to the repeater frequency. Sweet! I was able to keep on top of the whole incident easily on my 250D without having to wade through a bunch of unrelated traffic (including the massive amounts of encryption on this system). In fact, due to the constant issues ANY scanner has decoding our control channel, this method even snagged some comm's my BC796 missed. I was impressed to say the least. :D

While I was sitting there experimenting my only lament was having to press that button everytime the scanner stopped, that was a bit of a bummer. But, thanks to the wonders of computer control, I can create a little VB program to handle that for me.

Infact, that's what prompted me to post this trick. Since I'm going to be writing this little program anyway, is there any interest in me releasing it into the public domain for other BC250 or 750 users who don't have the $$$ to upgrade to a more current scanner, or just want something fun to do with their old digitals? What the program will allow you to do is to track any close by activity on your digital trunked systems so that whenever there is DTRS activity near you, you can listen in without having to camp out on the scan button. It will also automatically skip over encrypted comms whenever ENC appears on the display (who wants to listen to that stuff anyway). The downside is you'll have to keep your scanner tethered to your computer, but if that's not a problem then this program will be your ticket. Of course, it'll be a freebie, no sense in charging any money for such a simple program.

So, any takers? Post a reply here if you want it and if so then I'll make sure to code it a bit more robustly than I would if it was just for my own use. :D

-AZ
 

mciupa

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I'm suprised that the membership is being so shy.:confused:

Personally , I can't take advantage of this program but I admire your ingenuity AZ . Perhaps you could post this "trick" in the WIKI . :)
 

SCANdal

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What is the big hurry?

mciupa said:
I'm suprised that the membership is being so shy.:confused:
It's not a matter of being shy.

The first message was posted around lunch time. The second around dinner time ON THE SAME DAY. Unlike a small hand full of people on this board, most members apparently have a life apart from scanning and computers and don't have the opportunity to check in for new posts more then once a day (myself included) and many let a couple of days pass before logging in.

I'm sure there will be a taker or two on his offer

SCANdal
 
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mciupa

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SCANdal said:
It's not a matter of being shy.

... most members apparently have a life apart from scanning and computers and don't have the opportunity to check in for new posts more then once a day (myself included) and many let a couple of days pass before logging in.
l
:roll:
<SIGH> I have NO LIFE.
310.gif
 
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ragtime88

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I don't have those issues in my area (or those scanners), but I'd love to look at your code if you're willing to share that, too. I do a lot of technical programming, but haven't seen yet any info on how to write a scanner control program. Thanks for the post.
 

KB9NLL

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I don't have that problem but for other reasons what I do is look up inputs or other frequencies from the FCC. The database here Isn't always complete. But I guess you didn't have to in this case since the inputs were a specific offset.

I don't have a life, but I don't have much of a internet life either.:lol:

:cool:
 

slicerwizard

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ragtime88 said:
I don't have those issues in my area (or those scanners), but I'd love to look at your code if you're willing to share that, too. I do a lot of technical programming, but haven't seen yet any info on how to write a scanner control program. Thanks for the post.
Scanner control isn't much more than sending ASCII command strings over a serial port and waiting for (and then processing) the scanner's response.

The first step is geting your hands on a protocol spec for your scanner(s), but you haven't listed them so we can't help you with that.
 

AZScanner

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An update - Got some preliminary code running this weekend. I ended up only having an hour or so to play with it in between all the other items on the "honey do" list this weekend. So far not bad, had a good time testing it last night when the PD airship roared overhead at 1AM waking up my whole house. I was once again able to follow the whole thing pretty easily by just running the program with the scanner attached. I'm using my BC796 because the commands required for both the 796 and my 250D will be the same.

This week I'll give it a good long test, button up the code so that you can specify which comm port the scanner is on, and I even thought I might set it up so that rather than requiring the inputs already be programmed in, the program itself would tune the scanner to each input and then switch over to the repeater side if a transmission was detected. That way you don't have to hog up a bank on your scanner with channels you wouldn't be listening to without the program, and you could use it on non standard channels (meaning channels that don't have a precalculated repeater offset - 158.475 could go to 155.795 or whatever, for example, whatever you want to set it to). Should be fun, and I'll release it with source so those who want to enhance it further can have some fun too. My days of writing scanner software for money are long over, so I don't mind sharing so long as what I write doesn't end up in a commercial product later on (unless I get a royalty, ha ha).

Give me about 1 week folks and I should have it ready to go.

-AZ
 

AZScanner

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Hey folks, I haven't forgotten about this. Just swamped with work and other more pressing projects at the moment. I'll still try to get some time in to finish up the code. It's just about done, I just need to add a way to select the comm port and tune the mobile/repeater frequencies from a text file rather than the scanner memory. FYI.

-AZ
 

AZScanner

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Dear lord, I'm such a total slacker. I never posted this program after all that banter. Totally forgot about it as a matter of fact. How embarrassing. I was doing a forum search on something totally unrelated and found this thread.

I have the code for this kicking around somewhere, so if I find it, I'll throw it up on a free website somewhere and let the community have at it.

-AZ
 
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