Sport-Touring.Net

I'm trying to use a bluetooth helmet communication set. I'll be using on the new Shoei GT AIR-2.  The Sena SRL-2 bluetooth units are designed to be used w/ these helmets. Can anyone tell me how these units work, and can they be used as a ptt (push to talk), and are there remotes to do so. I just need intercom, music and gps. Sena wasn't all that helpfull with my requests. Also, Sena cant exchange or have the chargable batteries when they go bad, so what do you do after the 2 year warrentee is up when they do ?  Are they reliable? my J+M radio comms and cables are getting old and combersome

     Thanks;
                  Howie...

No push to talk…but you don’t have that with a phone either, right?  You just talk and the other person can hear it, just like a phone conversation.  Sure there are times where both people talk at once, but just like a phone conversation you work it out. Sometimes the GPS breaks in when someone is talking too.  So you ask them to repeat themselves. No big deal.

As far as replacement batteries.   No Sena does not sell replacement batteries. But other do.  I had a battery fail in a 10S unit I had.  I found a replacement on eBay for about $20.  It took me about 20 minutes to replace it….there are several videos on YouTube that show you how to do it.  It’s still working a few years later.

 OK, please explain how this is done w/ a cell phone w/ no cell service, have music and GPS speaking directions. TNX...

The Sena has a 1/4 mile (I Think) range on BT.. Sena -> Sena...  It's not using cell service...   The cell phone even without service can play MP3s and do GPS if you download maps (and music) in advance.  

That's what I do with my Sena knock-offs -- though they have a greater range and matrix capability Sena's don't so I've got a better range --- they're probably also breaking FCC rules :(  ...  

Using Bluetooth technology.  The Sena units can link to your smart phone and/GPS units that have Bluetooth capability. They can further link to each other through what is referred to as a daisy chain, or in the 30 and above units via a “mesh”.  How does it all work?  I have no idea, I just know that it does.

Now, that doesn’t mean that if you are somewhere that you don’t have cell service that you will still be able to make and receive phone calls.  Or that if your GPS unit loses its signal that it will still display its maps and give you directions. But the Sena does not rely on cell service to LINK to other units or to link to you phone/gps/radar detector.

Oh cool -- Sena added matrix / mesh communications!!  Maybe my knock-offs are no-longer illegal... They've been doing matrix for years ...  basically each unit can serve as a relay / repeater for other signals -- they either operate on multiple BT frequencies simultaneously likely or could alternately use multiple "privacy codes" to receive a message and retransmit it.  I got the knock-offs instead of Senas years ago specifically for the matrix capability when riding with up to 6 people and the extended range it offered.        



GPS will work regardless -- mapping software needs maps -- and they normally get downloaded in realtime on your phone -- BUT you can pre-download maps for an area and keep them on your phone.   That's probably already occured and they're stored in cache for areas you travel often.  You should also prepare your soundtrack, streaming music wont work if you have no cell signal..  A dedicated GPS has permanent maps in it.  

 When my Garmin starts up it always takes a few minutes to show my position on the map.  Says “acquiring signal”.  Then when the signal is acquired it shows my position on the map, and will continue to do that as long has it still has a signal. It’s not that it loses the map, it’s that it loses where I’m at on the map.  Doesn’t happen often, and usually when it does it’s only for a few seconds, but it can and does happen. Now that’s not necessarily a problem if I’ve created and downloaded a route into the unit before leaving home.  But many times I just head out on a ride without a route or clear destination, just a direction. Not having a connection child be a problem. if I can’t tell where I’m at, I won’t always know which direction to head in. I don’t remember that ever being a problem when I had a route loaded  :headscratch:

On startup the GPS has to acquire multiple satellites and time signals to "triangulate" your position.   If you block the line of sight with several satellites the GPS and lose signals the GPS will also lose it's position - driving between two tall buildings for instance...  If the unit's time is off, you'll have issues re-acquiring satellites-- they often have a battery operated clock inside.  AND if it's been moved a long distance while off, it'll also have issues.      



They should be independent of each other ...  IE the availability or lack preloaded maps and routes shouldn't affect the GPS signal location capability of a dedicated GPS unit.   On a cell phone, (google maps, waze, etc) it might cause a problem in the edge case where the phone needs to download map for the next quadrant /county / etc and it doesn't know which to get...  

Here’s the way my things are linked….

My Garmin GPS works as kind of the central unit.  My phone is linked to the GPS and my Sena is also linked to the GPS.  So my phone sends a signal to the GPS.  The GPS then sends a signal to the Sena headset.  If I turn off my headset and leave my phone on, my music then plays through the GPS external speaker. The route directions will also come out over the GPS speaker.  If I turn off the phone, the music will stop, but I will continue to get directions over the headset. If I turn off the GPS it will take a second or two for the phone and headset to pair up, but once they do I will have full functionality of the phone to listen to music or take calls. I can control some of this with voice commands, or do it physically. When I get directions or take a call, the music automatically goes quiet.

When I’m riding with others and we are linked up or in a mesh it works like this….say we are having a conversation and in the middle of the conversation I get a phone call.  If I answer the phone call I will lose my contact with the other rider(s). After I hang up it will reconnect.  If route directions come on in the middle of the conversation I will generally need the other rider to repeat what they said as the directions will override the conversation. I can still have my music playing during all of this and it will fade or increase volume as needed, but it generally plays as background to conversation and directions.

None 9f it is perfect,  it compared to where we were just a few years ago, it’s wonderful and magical technology.

Looks like I'm a little late to the party here. See my recent post about Sena's support.