Group bike-to-bike comms: Anybody out there?

**sootie** · 18th September 2012, 16:07

Originally Posted by clint640

I could see that connecting via the 3.5mm jack into the radio would be problematic from the start so that just stays plugged in & covered up along with the power feed. All other connections apart from to the helmet are soldered in. I think to have any sort of decent system you are going to have to spend some time wiring it in. I got a pack with 2x radios, 12V chargers, speaker mics etc. Used the speakers out of the spkr mic in the helmets.

I even splashed out on gold plated usb extensions from dick smith for the helmet wire, they worked ok at first but started crapping out after not too much use. I think the dust has killed them. They are all nicely soldered & heatshrunk in too so no worries at that end. Soldering in mini-DINs was driving me nuts, fiddly damn things. I think I'll try 2xRCA next, cheap & readily available, having each line 'round the opposite way should make them easy to attach wearing gloves.

Be interested to know what you do for noise cancelling. If I could wire a little black box inline somewhere so the system is usable at 100+ km/h that would be pretty groovy.

Even just with 2 people comms is quite useful, we do a bit of exploring on our adventures & 2 sets of eyes are better than 1 when trying to find that obscure track/ faded sign/ nice cafe.

Cheers
Clint

Have to query the helmet connector bit. We must have 6 or 8 Miniature DIN helmet connectors in use now - all OK, but I wired them all, and it is fiddly. Are you sure the problem is not the radio jackplug? - what happens with a wiggle on each?

Only one guy actually using USB at present, and he is having some helmet connection problems. I have never serviced that unit. Maybe I will look closer at it. My Quick Fit radio (see Album) is made up & working, but it is a trial unit, untested at this stage.

The noise cancelling bit is important at both the transmit and receive ends.
Wind noise over 100kph is a problem, but we have it tamed (but not eliminated!) in some installations including mine, and the Baehr setup one rider uses. (Below 80kph wind noise is barely noticeable.) I can (& usually do!) actually enjoy classical music from an mp3 player at 100kph plus!

My microphone set up is a direct copy of what Baehr recommend ie it is recessed into the helmet polystyrene, directly in front of the lips. It has some windage foam over the hole, and I can touch the foam quite easily with my tongue, so the air gap is quite small. After that, it is very important to get the microphone level right. Baehr have an adjustment pot, I pad my mic with a select on test resistor.

I adjust using a yell test (!) ie Rider wears closed helmet & is told to speak to the guy two properties down the road. I adjust the level for transmission as received just beginning to overload. This works pretty well!
I am not too sure about the Baehr noise cancelling description - it may be advertising bullshit! ??

I have now gone back to a unidirectional mike. The noise cancelling ones do not work well in a confined space.
Other guys at present argue whether the Baehr transmission or mine is better at speed. Both seem pretty good.
My system is just well set up. I have yet to find any electronic or acoustic noise cancelling scheme which works well enclosed in a close fit helmet. (Noise cancelling mikes work brilliantly out in the still air as aircraft pilots use them.)

I guess that still leaves the receive side, but your eyes are probably glazed over! Please have a look at my album first. The next bit involves what the US air force pilots do! I can't match that research budget!

:

**clint640** · 18th September 2012, 16:31

Originally Posted by sootie

Have to query the helmet connector bit. We must have 6 or 8 Miniature DIN helmet connectors in use now - all OK, but I wired them all, and it is fiddly. Are you sure the problem is not the radio jackplug? - what happens with a wiggle on each?
:

I've done so much wiggling I could be a childs entertainer

It does seem to be the helmet end connector. With our setup the radios usually stay bolted to the bikes & plugged in unless we are stripping down for full on dirty action so the radio end jackplug is rarely moved & just sits there covered up & coated with electrical CRC. If I still have issues after new helmet connectors I might go your way & wire directly into the radios but I have tried to avoid hacking them up so far. When it all works tx, rx, range is all acceptable apart from at tx noise at 80k+ speeds.

Cheers
Clint

**sootie** · 18th September 2012, 17:07

Originally Posted by clint640

I've done so much wiggling I could be a childs entertainer

It does seem to be the helmet end connector. With our setup the radios usually stay bolted to the bikes & plugged in unless we are stripping down for full on dirty action so the radio end jackplug is rarely moved & just sits there covered up & coated with electrical CRC. If I still have issues after new helmet connectors I might go your way & wire directly into the radios but I have tried to avoid hacking them up so far. When it all works tx, rx, range is all acceptable apart from at tx noise at 80k+ speeds.

Cheers
Clint

We are having a problem with the USB helmet connector which Michael uses. I have not ridden with Michael over the winter, and I never wired this connector set up. After your comments, I will take a bit more interest.

Some of the Uniden radios have a metal sleeve jackplug socket on the radio. So far these have been OK, but none have done more than about 5,000km service at this time. Other unidens use a plastic sleeve. All plastic sleeve jackplug sockets from anywhere fail in my experience. It is only a matter of how long it takes, and it can be anything from 500 to 5,000kms. I don't think we have ever had one last longer than this. (We had a plastic insert Uniden radio fail on the Baehr installation when Keith & I did a run together around the lower NI at the end of last summer.)

The other issue is the jackplug itself. I will only accept moulded plugs now. Any of the self assemble type (eg from Jaycar) will fail with motorcycle vibration. (They are just too cheaply made for consumer use.)

One of my favourite sayings is, "stick it in the concrete mixer for 20 minutes; if it still works when you take it out, it might survive our next motorcycle tour".

Range is absolutely no issue. I have had over 1km zig zagging through wet rainforest from my big high aerial to rear mounted radios. We regularly use comms at 5kms (but I would not rely on it), and we have made 10 kms across the Waikato plains.

**Hitcher** · 18th September 2012, 17:50

Originally Posted by sootie

It was actually a Goldwing rider that got me started on this.

I'm not sure whether your confession makes me feel happy or really sad.

**sootie** · 18th September 2012, 19:10

Originally Posted by Hitcher

I'm not sure whether your confession makes me feel happy or really sad.

Maybe I should tell you a bit more of the story.
- Never rode in groups much until I joined this present group a few years ago.
- Enjoyed my first experience in spite of the need for an extra comfort stop, being left behind at intersections etc
- about half way through the ride the leader got totally lost (I am sure all of this is all very original!)
- Leader signals the problem as best he can - bikes to left, bikes to right, bikes in the middle, cagers swerving
- (close your eyes Victoria this may not be pretty)
- I was at the back, fairly safe beside this Goldwing Rider
- " Nothing like this f..ing mess should ever happen on a ride.
- In the Gold wing club / leader / radios /tail end charlie ... f...ing ridiculous ... etc etc"
- In a fit of madness I said "maybe I can do something about this" (I have some radio engineering background)

This guy wound up with one of the first bikes I ever fitted out. It was basically Pinfold gear designed to work in with the Goldwing / cellphone setup he already had. It worked OK for a little time & then failed miserably & totally. (My first jackplug experiences!)
At that point he went over to the dark side completely, and still only worships at the Goldwing Comms shrine.
We have tried repeatedly to rescue his soul without success in spite of later successes. No go.

So you see, I was left holding the baby ......

[Some of our mates when they read this:

:

:]

**FLUB** · 18th September 2012, 19:25

I've got an Autocom wired intercom with noise cancelling mics. I've been nagged very clearly at 150kph by my wife on the pillian so can testify that they work :-)

I'll double check at the weekend but I'm pretty sure it's a passive system with two mics back to back but wired out of phase. Any sound picked up by both mics, such as wind noise, is cancelled out. Sound on just one mic (the one facing your mouth) gets through. At least that's the theory.

Are we winning the prize yet for the most geeky thread on here?

**sootie** · 18th September 2012, 20:03

Originally Posted by FLUB

I've got an Autocom wired intercom with noise cancelling mics. I've been nagged very clearly at 150kph by my wife on the pillian so can testify that they work :-)

I'll double check at the weekend but I'm pretty sure it's a passive system with two mics back to back but wired out of phase. Any sound picked up by both mics, such as wind noise, is cancelled out. Sound on just one mic (the one facing your mouth) gets through. At least that's the theory.

Are we winning the prize yet for the most geeky thread on here?

Hi John,
there are a number of audio noise cancelling techniques in use out there, and I have read up a few research publications on electronic methods but so far I am not very convinced re bike helmet use.
Gary is using an old noise cancelling mic from a car adapter fitted to a previous car my wife had. My impression is that it works well in the right position, but shift it 10mm in relation to your lips, and it gets noisy.
"Noise cancelling" has a great advertising ring to it - that's what matters now days!!

Passive noise cancellation mics work well for pilots with lots of still air airspace in front. Bikers don't have that available. Helmets give lots of irregular sound reflections in practice & make cancellation difficult. I keep hoping!
My mike is a copy of what Baehr use - see below. It works well at an airspeed of 160kph - a speed achieved with a head wind of course!

Nothing geeky yet mate - not even a single differential equation!

**FLUB** · 18th September 2012, 20:36

Let's not get started on calculus :-)

You're right about mic positioning and Autocom talk about the 'sweet spot', which is close enough that you can kiss the mic. This is easy as the mic has a very stiff boom and stays where it is put. Move it more than a couple of cm's away from this spot and it almost stops working. I guess this is because your voice is heard by both mics and cancels out. It certainly works and I've had it installed on 5 different helmets, although always on fully faired bikes so maybe that provides the still air.

Currently my wife and I use Sena SMH5 intercoms (rider to pillian, not bike to bike) and these also have minimal wind noise up to 120kph. Also behind a full fairing.

As we've already discussed via email. I'm considering linking to a radio via a bluetooth hub. This will get around the problem of dodgy helmet connectors but still has the weak link of the connection between the hub and tbe radio. Have you tried 'professional' jack or DIN connectors from a ham radio outlet or somewhere like RS Components? Whilst Dick Smith and Jaycar are great for man-cave stuff, you get what you pay for when it comes to connectors.

**sootie** · 18th September 2012, 22:06

Originally Posted by FLUB

Let's not get started on calculus :-)

You're right about mic positioning and Autocom talk about the 'sweet spot', which is close enough that you can kiss the mic. This is easy as the mic has a very stiff boom and stays where it is put. Move it more than a couple of cm's away from this spot and it almost stops working. I guess this is because your voice is heard by both mics and cancels out. It certainly works and I've had it installed on 5 different helmets, although always on fully faired bikes so maybe that provides the still air.

Currently my wife and I use Sena SMH5 intercoms (rider to pillian, not bike to bike) and these also have minimal wind noise up to 120kph. Also behind a full fairing.

As we've already discussed via email. I'm considering linking to a radio via a bluetooth hub. This will get around the problem of dodgy helmet connectors but still has the weak link of the connection between the hub and tbe radio. Have you tried 'professional' jack or DIN connectors from a ham radio outlet or somewhere like RS Components? Whilst Dick Smith and Jaycar are great for man-cave stuff, you get what you pay for when it comes to connectors.

If your helmet is out of the slip stream behind a windscreen that usually solves most wind noise problems (unless there is a lot of turbulence). It works well for Goldwing riders. My helmet is out in the open above the windscreen. Air flow is smooth, but you need a good setup to beat wind noise over 100kph or so. I do, & with a very simple setup which is a Baehr copy.

There are only about four connectors I am happy with at the moment. Rubber boot sealing DINs, DB9s, the old WW2 mike connectors which are solid and made from metal and a 3.5mm stereo Jaycar pcb mount jackplug socket which uses real springs for tension, along with a moulded jack plug. (Photos of all of these in my Album, except for the pcb mount jackplug) For lots of connections, including push pull speaker drive, charging, mike, PTT, stereo mp3 earpiece drive etc, I like the DB9s with long thumbscrew joiners which can be done up in gloves. They are not waterproof however! (Well, I did say I have to use consumer rubbish because of cost!)
All connectors need to be done by someone with a good soldering hand, and made mechanically robust.

I now like a bike setup which is just available like a car radio. ie I just jump on the bike any time, switch comms gear on and use it! This means powered from the vehicle ignition and all headset gubbons fully installed. I really don't now like things which have to be separately charged & which can let you down. Hence I am not keen on Bluetooth. Personally, I don't carry pillions much, but I would just give them a portable comms set & let them talk to everyone (including me) directly! Your wife might like chatting me up John!
(Separate charging or dry cells needed for pillion unit.)