DMR Tip 3 - Digital Monitor Modes

I’m going to cover “Digital Monitor”, what it is, does, and why you should use it.  I use an Anytone 868 & 878, but the general principle applies to all DMR radios with this feature or a “promiscuous mode”.

Digital monitor feature has three modes, “Off”, “Single Slot”, and “Double slot”.  You can set it in the menus (Click on the “Menu” button on the Anytone HT and tt’s the first menu item when you select the Up button).  Here, I’ll just be referencing the “switch” in that menu.  On my radio I have a button assigned to change the mode it’s in quickly so I’m not fumbling around in the menus.  I use this programmed button the most on my radios.. 

Here are the behaviors when using a repeater:

Off -- When digital monitor is off, the radio will only allow traffic for the talk group that you are listening to.  It’s similar to tone-squelch in the analog world.  So if you are on a repeater and you are sharing it with other hams having a conversation on the same time slot but a different talk group, you won’t hear their conversation at all.  You’ll only hear other operators when a) the time slot you are on isn’t busy, b) the ham is talking on the currently selected talk group on your radio.

Single Slot -- When the radio digital monitor “Single Slot” mode, you’ll hear any traffic on the timeslot you are tuned into.  You’ll hear any conversation on your talkgroup or any other talk group on the same time slot on the repeater.

Double Slot -- When the radio is in digital monitor “Double Slot”, you’ll hear any radio traffic on any time slot on the repeater.  Anything that is being broadcast on the repeater, you’ll hear it (as long as you have the correct color code setup for the repeater).

Why use Digital Monitor

OK, now that you know what it does, let’s talk about why you might use one mode over the others.

Off -- Use this mode when you are just motoring along and want to only listen to what’s going on in the talk group that you are tuned for.  On a busy repeater this is really handy since you may not care about all the wonderful things another operator has to say a different talk group, like “TAC 310”.

Single Slot -- I use this to monitor the repeater timeslot that I’m using so that I know when it’s safe to transmit.  Unless you are using your own hot spot, you are sharing the repeater with others and it’s always a good practice to listen before you mash on the PTT switch.  This is the mode I’m usually using.  If you find that you aren’t getting a permit tone on your radio when you transmit, and you really think you should be able to get into the repeater, turn on digital monitoring, it may reveal that you are being blocked by other operators already in a QSO.  If you are on slot 1, you'll hear all traffic on slot 1.  If you change change to a channel that uses slot 2, you single slot monitoring will listen to all traffic on slot 2.

Double Slot -- Sometimes you just want to be entertained or understand how people are using a particular repeater.  Double Slot mode lets you do just that.  Any traffic the repeater is handling, you’ll hear it.  If you are in an unfamiliar area, it might be interesting to hear what people are talking about or better understand how the repeater is being used.

Another reason to use Double Slot is when the repeater becomes disconnected from the internet and you want to use it like a stand alone repeater.  In an emergency, you may know which repeater to use to connect with your team but not which what talk group or time slot you need to be on.  Use Double Slot so you will hear (and see on the display) all the traffic on the repeater.  If your friend or team are using the repeater, you’ll not only hear them but the display on the radio will tell you which time slot they are on and what talk group they are using. 

What I’m using a hotspot?

Most hot spots act just like a repeater but they only have a single time slot.  

That’s It!

That’s all there is to the simple digital monitor modes and this is the most used portion of the “digital monitor” modes you’ll use.  I’ll cover the color code monitor and other options in a later post.

Take a look at some of the other tips and articles on DMR HERE.

I hope you found this tip useful.   Please use the comments section to submit your questions.

Thanks to KC2GNV for helping improve this article.

See more DMR TIPS HERE.

Enjoy and 73,

N1CLC

Christian Claborne

(aka Chris Claborne)