APRS RADAR

[JeepGuy91]

I recently learned a new trick with APRS that essentially gives you a form of Radio Detection and Ranging (RADAR) through APRS! It's called Voice Alert.

If you run APRS and are anything like me, you probably either turn your volume down or enable a mute function so you don't have to listen to incoming packets all the time.


Instead enable CTCSS:
100 in the US
136 in Europe
91 in Australia

(I've tested it, but only in the US, so I can't vouch for the other countries.)

Once this is enabled, make sure your volume is turned up. You will now only hear the packets of other APRS users who are also using Voice Alert. Since digipeaters don't relay the CTCSS tone, if you hear a packet, it'll mean that you're hearing a packet directly from the source (via simplex) and you'll be able to initiate a simplex voice contact. You can set your comment to the simplex frequency you're monitoring on voice, but you can also give (very brief) call out via voice on the APRS frequency to the station whose packet you heard and ask them to QSY to the frequency of choice. Voice will not relay over digipeaters either, so no worries there.

If you ask me, this is far better than randomly giving your call on .52 and hoping someone will hear and respond.

I recently tried using Voice Alert on a long road trip and I was surprised to find several other stations using it, primarily in Colorado. That said, if you're into using APRS, I encourage you to use Voice Alert! I think it could lead to a lot more simplex contacts, especially amongst overlanders!

Source: http://aprs.org/VoiceAlert3.html

 

[Ubiety]

Very cool! I just learned that voice alert and frequency alert are different. I had looked into frequency alert but my mobile (TM-D700) does not support it, however voice alert should just work if configured properly. Thanks for the pointer!

 

[JeepGuy91]

Very cool! I just learned that voice alert and frequency alert are different. I had looked into frequency alert but my mobile (TM-D700) does not support it, however voice alert should just work if configured properly. Thanks for the pointer!

I'm not familiar with frequency alert, but yes, voice alert should work on any radio capable of CTCSS/tone squelch. (Obviously some form of APRS is necessary too, whether built in to the radio, or with a separate TNC and interface such as APRSdroid.)

Thanks for the response!

 

[Ubiety]

Frequency alert is similar. Basically you can tack a voice channel onto your APRS beacons and someone receiving those, with the correct radio, will have their radio automagically tune the second band to that voice frequency received via APRS. I think - never had succes with it because my mobiles do not support it (TM-D700s) but I’ll bet tHe new TH-D74 does!

 

[JeepGuy91]

Frequency alert is similar. Basically you can tack a voice channel onto your APRS beacons and someone receiving those, with the correct radio, will have their radio automagically tune the second band to that voice frequency received via APRS. I think - never had succes with it because my mobiles do not support it (TM-D700s) but I’ll bet tHe new TH-D74 does!

Interesting! I'll have to look into that.

 

[Tortoise Overland]

News to me, I have an FTM-350. I am going to have to try this out.

 

[JeepGuy91]

News to me, I have an FTM-350. I am going to have to try this out.

How do you like the 350? I'm considering installing a radio in my trailer so I have a base camp comm set up. Initially I was thinking of using the 400, but the 350 intrigues me a bit.

 

[Ubiety]

How do you like the 350? I'm considering installing a radio in my trailer so I have a base camp comm set up. Initially I was thinking of using the 400, but the 350 intrigues me a bit.

Note sure if the Yaesu's allow you to access the TNC directly which might be a fun thing to do at a base camp (e.g. WinLink, more advanced APRS, etc.). Kenwoods do allow you to muck about directly with the TNC.

 

[JeepGuy91]

How do you like the 350? I'm considering installing a radio in my trailer so I have a base camp comm set up. Initially I was thinking of using the 400, but the 350 intrigues me a bit.

Note sure if the Yaesu's allow you to access the TNC directly which might be a fun thing to do at a base camp (e.g. WinLink, more advanced APRS, etc.). Kenwoods do allow you to muck about directly with the TNC.

I don't believe they do, however I purchased a mobilinkd2 a while back to use the APRSdroid interface wirelessly.

 

[M Rose]

I don't believe they do, however I purchased a mobilinkd2 a while back to use the APRSdroid interface wirelessly.

The TNC2 is nice. I have the upgraded 3. I’m thinking about buying one more that will live in my go box.

 

[Tortoise Overland]

How do you like the 350? I'm considering installing a radio in my trailer so I have a base camp comm set up. Initially I was thinking of using the 400, but the 350 intrigues me a bit.

I like it alot. Easy to use. Can't find many used. And the APRS module is hard to find if you buy one without it. Check me out on APRS.fi N3MFL-9

 

[M Rose]

I like it alot. Easy to use. Can't find many used. And the APRS module is hard to find if you buy one without it. Check me out on APRS.fi N3MFL-9

I didn’t know the 350 came without the APRS module. As for finding it used... it’s been out since July. So finding it used will be very hard.

 

[Tortoise Overland]

I like it alot. Easy to use. Can't find many used. And the APRS module is hard to find if you buy one without it. Check me out on APRS.fi N3MFL-9

I didn’t know the 350 came without the APRS module. As for finding it used... it’s been out since July. So finding it used will be very hard.

The FTM-350 has been out for more than 3 years now. The FTM-400 has been out for 2 years. The APRS module is an option just like the Bluetooth module.

 

[M Rose]

The FTM-350 has been out for more than 3 years now. The FTM-400 has been out for 2 years. The APRS module is an option just like the Bluetooth module.

I was confused the FTM-350 has been discounted for 2 years from what I just pulled up from Yaesu. The FTM-300DR is the radio I was thinking of that was just released and has the built in GPS/APRS (not a separate module). It also has built in Bluetooth module right out of the box, not an external accessory.

 

[JeepGuy91]

The FTM-350 has been out for more than 3 years now. The FTM-400 has been out for 2 years. The APRS module is an option just like the Bluetooth module.

I was confused the FTM-350 has been discounted for 2 years from what I just pulled up from Yaesu. The FTM-300DR is the radio I was thinking of that was just released and has the built in GPS/APRS (not a separate module). It also has built in Bluetooth module right out of the box, not an external accessory.

I was confusing the 300 and 350 as well!

 

[Trad77]

I recently learned a new trick with APRS that essentially gives you a form of Radio Detection and Ranging (RADAR) through APRS! It's called Voice Alert.

If you run APRS and are anything like me, you probably either turn your volume down or enable a mute function so you don't have to listen to incoming packets all the time.


Instead enable CTCSS:
100 in the US
136 in Europe
91 in Australia

(I've tested it, but only in the US, so I can't vouch for the other countries.)

Once this is enabled, make sure your volume is turned up. You will now only hear the packets of other APRS users who are also using Voice Alert. Since digipeaters don't relay the CTCSS tone, if you hear a packet, it'll mean that you're hearing a packet directly from the source (via simplex) and you'll be able to initiate a simplex voice contact. You can set your comment to the simplex frequency you're monitoring on voice, but you can also give (very brief) call out via voice on the APRS frequency to the station whose packet you heard and ask them to QSY to the frequency of choice. Voice will not relay over digipeaters either, so no worries there.

If you ask me, this is far better than randomly giving your call on .52 and hoping someone will hear and respond.

I recently tried using Voice Alert on a long road trip and I was surprised to find several other stations using it, primarily in Colorado. That said, if you're into using APRS, I encourage you to use Voice Alert! I think it could lead to a lot more simplex contacts, especially amongst overlanders!

Source: http://aprs.org/VoiceAlert3.html

YES!!! Voice Alert is the only way to run APRS. I have been using it for years and I have had more QSO's this way than running without it. Glad you posted this, more hams need to know about it.

 

[Tortoise Overland]

How do you like the 350? I'm considering installing a radio in my trailer so I have a base camp comm set up. Initially I was thinking of using the 400, but the 350 intrigues me a bit.

I love it, I have 2. One with GPS module, the other without. I can't seem to find another GPS module. Great radio though.

 

[2xAGM114]

My only APRS radio is a HT. For the APRS "Radar" to work, does the GPS have to be turned on? The GPS + APRS Modem runs down the battery in a matter of hours if the APRS Beacon rate is set too low. I keep the GPS turned off unless I'm doing a SOTA hike or similar operation.

 

[JeepGuy91]

My only APRS radio is a HT. For the APRS "Radar" to work, does the GPS have to be turned on? The GPS + APRS Modem runs down the battery in a matter of hours if the APRS Beacon rate is set too low. I keep the GPS turned off unless I'm doing a SOTA hike or similar operation.

No, GPS does not have to be turned on. You could be beaconing packets for a fixed location. The only real requirement is to have CTCSS on. That said, if you were using the HT in a vehicle, I'd turn it on and use a 12v car charger to keep the battery topped off.

 

[Ubiety]

My only APRS radio is a HT. For the APRS "Radar" to work, does the GPS have to be turned on? The GPS + APRS Modem runs down the battery in a matter of hours if the APRS Beacon rate is set too low. I keep the GPS turned off unless I'm doing a SOTA hike or similar operation.

For mobile APRS if you want to leave a breadcrumb trail then yes, leave the GPS on. A lot of APRS software that I have seen allows you to "hardcode" your position and this is great for a stationary station. My iGate never moves, or it should not, so I have hardcoded its position into Xastir (its operating software). I mean I guess you could leave your GPS off and enter a new position occasionally but this would become a real hassle very quickly. I guess it depends on your use case.

@JeepGuy91 nailed it when he said to power your gear off of the car's electrical system.

This is part of the reason I love having a dual band APRS capable mobile in the truck. I turn the power on and forget it and can talk on the other channel.