If you have not read My TAC-Comms System: Part 1 please do so…



First we need to get the CHIRPS Programming Software. While the RT6 comes with a Windows software package, I prefer Linux and to use CHIRP for all my radios if possible as it allows for easy cut and paste of frequencies between radios.

If you are using Linux, you might find my Linux Cheatsheet for HAMs helpful, otherwise follow the installation instruction on the CHIRPS website for your OS.

I’m not going to reinvent the wheel and show you exactly how to use CHIRPS because David Casler has already done a terrific job of this and has many more great tutorials on his YouTube channel.  Go check him out and watch his Using CHIRP to Program your Handheld Ham Radios, AD#38.

Back already?  Great.

Later you will want to experiment with adding local repeaters via CHIRP and the REPEATERBOOK.COM option inside of it, but for now…

You can download the my RT6 demo file for the freqs used in this article at:  https://drive.google.com/open?id=1QLqc9b-Dp1fFy9vAgpd07FMXMU2oIczo

One you have CHIRPS installed and the demo image opened, take a look at the first three channels, TAC 1-3 which will be the ones dealt with in this post.

These are your “Tactical” channels that will be used in Simplex mode for day to day comms between groups.  I have three TAC channels setup as I anticipate three potential MAGs in my AO.

I recommend setting up a TAC channel for each group to use between themselves and then  a “REACT” channel for all the groups to monitor.

Better yet is a Repeater Channel for Regional Comms beyond line of sight.  I cover setting up the repeater in my portable solar-powered cross-band repeater article.

Feel free to change the frequencies in the demo image to your own or use the ones I’ve put in the sample, as they are not my actual systems freqs for obvious OPSEC reasons. 🙂



click to enlarge


By setting the ToneSql value we are only allowing transmissions into our radios that have the specific CTSS value (TAC 1 = 88.5), any person using 146.4200 without a CTSS of 88.5 will hear you but not be able to talk to you or more importantly, interfere with your comms.

Interference is probably not going to be much of an issue on HAM bands since there are many more freqs and not just standard channels like FRM/GMRS/MURS, but better safe than sorry thanks to the huge influx of cheap HTs like the Baofeng UV5R that “Purchase Preppers” love to get.

More importantly, the CTSS ToneSql settings will prevent QRN from opening your squelch and giving away you position.  Always use ToneSql on your TAC channels!

The DTCS Code is 023 by default, we are not using it in this article.  DTCS is no different than CTSS for our purposes and provides not greater “security”.

Also the Tone does not need to be set when using TSQL because it automatically uses the ToneSQL value for TX and RX, (see Linux Cheatsheet for HAMs for more) but it won’t hurt to match them up as I have.  If later you decide to use another Cross Mode, this value could be needed.


ABOUT SECURITY:  I want to make it clear that, nothing in any of these articles is going to set you up with a “secure” network over the air that allows you to speak and not be decoded.  All transmissions in analog armature radio are not encoded, it’s actually against the law to encode/encrypt them.

If you have the money to setup a similar system on Digital radios with  sudo-encryption and can afford a digital repeater (big money) then have at it, but then again if you have that much money you are not reading this article. 🙂

If you are looking for a more secure simplex only setup, then checkout my The Perfect Prepper HT? post.


The reason for three TAC channels is that if someone does “skim” your CTSS code and start talking on your channel when you don’t want them to, you can advise the group to move to “TAC 3” and the OPFOR will have to find your Freq. and CTSS code for that channel.

It’s a temp fix for a compromised channel and if they captured your CTSS, it probably means are keying up too long, giving them time to capture it, or they have advanced Signals Detection capabilities beyond your average “Bubba” or beginning HAM Operator.


The demo below shows why you want to have your radio only open squelch when another team member is trying to contact you.

The first demo is a sample of static interference (QRN) and the second is showing how just having your tone set will still allow anyone to break into your channel.

This is why you need to have TSQL set for mode and a CTSS value in ToneSql which will be used to receive and send transmissions.

The image below shows the settings for each radio in the video.

click to enlarge


click to enlarge

If you look at the demo file you will see that I have FRS/GMRS/MURS/SEA (Marine Channels) along with local repeaters in my memory banks.  Also, don’t forget your local WX channel (importable from CHIRP) as they are of great value while the reports continue to air.

One thing to note is that blocking a busy channel is a pain if you have a lot of them to handle in the field at once, so I limit my scanning to the “Bubba Freqs” listed above and only scan to know if someone using them in my AO (line of sight ~ 2 Miles for VHF/UHF).

I’m not scanning the other channels in my system, they are being used by other MAG’s as their own simplex channel.

Because the radio is a dual monitor type and does not have two VFO’s it can not listen to two separate signals at the same time like higher end radios.  Since there is only one VFO in these radios I’ll call the display levels; Level 1 and Level 2 to distinguish between the monitoring of it’s single VFO.

I will normally have “Level 1” set for monitoring my own TAC channel and “Level 2” scanning the “Bubba Freqs”.

I always have Level 1 set to a system channel and only transmit on Level 1 to keep from getting confused and transmitting outside of my system by accident while scanning.

In high risk times there is an exception to the rule.  When a REACT Team response might be expected, one “Level 2” is set for the designated Repeater/REACT channel to listen for comms from the other MAG’s and “Level 1” is set to my own MAG’s TAC channel.


You should have a programmed radio by this time and proper ToneSql operation.  If there are any questions, please comment below so I can improve the article by addressing them.

In Part 3  will be building the End Users Guide.

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