GMRS mounted in Tail of bike a problem?

[ShinySideUpAZ]

Question? When you are doing this test, are you transmitting with a radio in one hand and one in the other hand hooked to your helmet? If so, with some radio's this is a problem. The first attempt my wife and I made at driver to passenger communication was to use two Cobra FRS radios. I had already purchased headsets that were compatible with the radios, and we had been using the radios sucessfully in car to bike communication. However, when we sat together on the bike, the transmissions were garbled and full of interference. If we stood several feet apart, the signal was good.

 

[dmulk]

Question? When you are doing this test, are you transmitting with a radio in one hand and one in the other hand hooked to your helmet? If so, with some radio's this is a problem. The first attempt my wife and I made at driver to passenger communication was to use two Cobra FRS radios. I had already purchased headsets that were compatible with the radios, and we had been using the radios sucessfully in car to bike communication. However, when we sat together on the bike, the transmissions were garbled and full of interference. If we stood several feet apart, the signal was good.

Nope. Just the one radio.

Whether it is connected to the bike or not, I can hear the engine noise through the speakers in my helmet on transmit only....only, it's not the mic on the helmet feeding back because I have VOX off and it is a static noise sound.

I am going to wheel the bike out of the garage and retest it tomorrow night after work....unless someone else comes up with some suggestions to put on the list...

It is so frustrating to be so close.... I mean....the *only* noise I get at this point is on transmit of the radio....if I hold the "monitor" / squelch off key on the radio, it sounds fine at any RPM.

Thanks,

<D>

 

[Blrfl]

Whether it is connected to the bike or not, I can hear the engine noise through the speakers in my helmet on transmit only.

Okay, the plot thickens. I thought you meant the receiver at the other end was hearing noise. Your problem may be with the proximity between the antenna and Starcom.

I've never put any effort into determining why, but for some reason the presence of RF in the 400-470 MHz range induces noise onto nearby electronics. You don't even have to be close by. I can key up at low power (0.5W) as much as 10 feet away from my stereo or a pair of computer speakers and I get a hum out of them. If I have one of my old analog TVs on, the picture is sometimes visibly affected. Your Starcom may be experiencing the same thing. My Autocom, interestingly, does not suffer from this problem even though I have a TK-350 in the tail with the antenna right on top of it.

If you want to try a just-for-laughs experiment, wrap your Starcom in a couple of layers of aluminum foil and see if the situation improves any.

--Mark

 

[dmulk]

If you want to try a just-for-laughs experiment, wrap your Starcom in a couple of layers of aluminum foil and see if the situation improves any.

--Mark

Funny you should mention this.... I have suspected that because the Starcom's case is made of metal, that it is somehow conducting. SO I called an electrician buddy of mine and he said that he would send me over some copper mesh to wrap the unit in as a test.

....I think while I am at it, I'm also going to line my helmet with aluminum foil to block the alien's transmissions.... :hotpepper



Thanks again for all of the help... I'll eventually get to the bottom of this....(it might even be by purchasing an Autocom system....)

<D>

 

[Blrfl]

I should have added that at such close range, foil probably won't make a whole lot of difference. But if you're going to try it, ground it.

--Mark

 

[ShinySideUpAZ]

It is not enough wrap the Starcom in copper, you must ground that copper to the frame to create a faraday cage.

 

[dmulk]

It is not enough wrap the Starcom in copper, you must ground that copper to the frame to create a faraday cage.

Yup. That's the plan... Either that or throw in the towel and pull the trigger on an autocom...

<D>

 

[dmulk]

Well Richard (Mr.Moody) and I hacked on this for another hour and no matter what we did, the static was always present when transmitting from the bike.

We could hear it on the receiving radio (not on the bike) and I could always hear it in my head set.

When I disabled the Side-tone (I use in ear speakers) I could still hear it in my head set.

If the engine if off, it is crystal clear (receiving and transmitting)

If the engine is running (idle) there is a little constant static during transmit (on both ends - in my headset and on the hand held). If I rev the engine (4-5KRPM) the static is louder, increasing with RPM.

However, things are crystal clear, at any RPM on receiving...(Richard standing across the street transmitting).

If I unplug the radio from the starcom, the transmitting is fine.

When the radio is connected to the Starcom, if I lift the radio about 2 feet, straight up from the Starcom, while holding the transmit button, the static decreases significantly. About 3-4 feet above bike, it is gone. I can then slowly move it down to the starcom (tail of bike) and it returns gradually as it gets closer.

Again....only on transmit.

I am starting to think that the electronics in the Starcom are just more sensitive than Autocom (All I hear about on the Autocom is "alternator" or Ground loop" noise....easily solved with Powerline and GL filters).



:banghead: :banghead: :banghead: :banghead: :banghead: :banghead:

 

[Finewest]

I have been following your threads in regards to your Starcom and comm. connections Dan and I have been feeling your pain.

I know that you wanted to go in the direction of putting all the stuff under seats and fairings, and you have been having a lot of static and electronic feedback noise. I get those too. I have, I feel, solved some of it, but in a different fashion and one to consider if you wish to re-construct your setup. As you know I use a tankbag to hold all my comm. and music devices along with the Starcom itself and all the snakey wiring that goes with (though I have some ideas on minmizing that). For my music (satellite radio and mini-disc player) I have a 3.5mm plug audio cable that has a noise filter on it, and man! That baby is cyrstal clear. Got it at Crutchfield and you could use it as a audio cable adapter connection. I have also read on other threads, and have discovered for myself, that devices not powered to the bike such as battery operated devices do not pick up the bike's electronics and motors, but once you connect the device to bike power you get noise.

I would try the inline noise filter plug adapter cable I mentioned and simplify the setup as much as possible. And this is advice from a dude who don't know poop about electrical and magnetic noise fields and crap! LOL. I just feel your fustration, and my setup is working so nicely. It just don't seem fair! LOL!

See ya for TechSTOC!

 

[dmulk]

Now, ya see, all it took was a post from my friend Fred and I get some luck to go my way....

I may actually have to seriously rethink my "tail setup"....but this is so hard for me to give up because, ergonomically, it just all fits in there so dang perfect!

So, anyway... I am out in the garage and I see out of all the "electrical voodoo" I have purchased over the last couple weeks and I have an extra choke that came in a two pack from Radio shack.... these are the rectangle type. (These)


I flip through the instructions and I see that they are made to clip together in series. So I clip two of them together and coil the power cord from the centech to the starcom, closest to the starcom....and I hear significantly reduced static when I hold transmit.

I also moved the grounding point of the Centech Fuse box from the seat adjustment bracket to the negative on the battery. WAY less static on transmit. (Moving the ground I think made the most difference - I read an article about similar problems on an FJR forum and they said the FJR is designed to bleed all of it's electrical noise to the frame...they were pretty adamant about grounding accessories to the battery).

I think the key to getting completely silent may be moving to a small external antenna. I know Turbo Tom makes a special bracket mount for this (RickJ has one) and I really like it.... but if I can get "usable" noise levels with out this....I'll forgo the antenna.

While I am not completely noise free, I did at least accomplish something... I got the my Zumo hardwired and cleaned up some wiring that I wasn't happy with. It's great... the Zumo now powers up with the ignition. Used the black plug on the quartet harness. Since the Zumo has battery power also, I can use it in the parking lot when stopped, without running the bike's battery down. The Zumo senses when the engine is turned off and asks if it should stay on...otherwise, it shuts itself off in 30 seconds. Nice feature.

Anyway... I really think the Starcom at this point is way more sensitive to electrical noise than Autocom....just from what I have read....I guess I may end up switching in the future if I can't get happy.

I will be sure to check out your setup at TechSTOC next weekend,Fred. Thanks for feeling the pain with me...misery likes company...!!!

<D>

I have been following your threads in regards to your Starcom and comm. connections Dan and I have been feeling your pain.

I know that you wanted to go in the direction of putting all the stuff under seats and fairings, and you have been having a lot of static and electronic feedback noise. I get those too. I have, I feel, solved some of it, but in a different fashion and one to consider if you wish to re-construct your setup. As you know I use a tankbag to hold all my comm. and music devices along with the Starcom itself and all the snakey wiring that goes with (though I have some ideas on minmizing that). For my music (satellite radio and mini-disc player) I have a 3.5mm plug audio cable that has a noise filter on it, and man! That baby is cyrstal clear. Got it at Crutchfield and you could use it as a audio cable adapter connection. I have also read on other threads, and have discovered for myself, that devices not powered to the bike such as battery operated devices do not pick up the bike's electronics and motors, but once you connect the device to bike power you get noise.

I would try the inline noise filter plug adapter cable I mentioned and simplify the setup as much as possible. And this is advice from a dude who don't know poop about electrical and magnetic noise fields and crap! LOL. I just feel your fustration, and my setup is working so nicely. It just don't seem fair! LOL!

See ya for TechSTOC!

 

[dmulk]

Ok.... I am SO VERY close to getting this to work!

Actually, I think that I now have a usable level of "noise". As ridiculous as that sounds...

I hooked up my Zumo's isolated Mic and Audio cable and I am able to hold the revs of the bike at 5-6K RPM and the sound is crystal clear.

The only noise I get through the system now is a "static rev" (not the alternator 'whirring'...but static) when I transmit on the Kenwood GMRS radio.

The two biggest changes that made the most difference were:

1) The Radio shack chokes posted above wrapped around (an already isolated) power line between the starcom and the fuse block.

2) Grounding to the Battery.

So I am getting excited and I hookup my PTT switch and I find it not working....so I 'flex' it at the starcom box and I am fairly certain that the starcom connection for the PTT is faulty....gonna pull the board and check the solder points....:banghead:



<D>

 

[dmulk]

So I have the system "usable". Like Matt, I am finding I get some whine after the bike warms up and if I turn my Zumo off, it increases. It's still tolerable and I will probably put my home made 20AMP power filter back in and retest at some point.

On another note; VOX.

If I ride with my helmet screen down (Shoei X-11) and the windscreen down, anything over 55MPH holds the VOX setting open. I Have played with MIC sensitivty setting from 1/2 way to completely off. and VOX to barely on to midway....nothing seems to change it.

I added a larger microphone foam thingy from my old chatterbox and while that helped, it didn't cure it.... anything over 55MPH is useless.

Unfortunately, PTT function is broken....not sure if it is the switch or the plug on the unit. Will be sending both back to CalSport touring on Monday. It came like this, so one or the other is defective...

Anyone use a Starcom with VOX exclusively and like it?

One more question: Noticed that when I sync'd my Razor to the Zumo and then through the Starcom the Volume is extremely low when the caller speaks....anyone else have an issue / advice?

Thanks,
<D>

 

[dmulk]

Does anyone have the pin-outs to the Starcom headset PS2 connections?

Thanks,

Dan

 

[ShinySideUpAZ]

Does anyone have the pin-outs to the Starcom headset PS2 connections?

Thanks,

Dan

Here you go:

 

[dmulk]

Where would I be with out you MARK!??!!

Thanks man!

<D>

 

[dmulk]

Mark,

Do you happen to also have the pin outs for the head set connection plugs on the circuit board side?

 

[ShinySideUpAZ]

Mark,

Do you happen to also have the pin outs for the head set connection plugs on the circuit board side?

Same as the headset, just match them up.

 

[dmulk]

I am talking about the board side connector (Its a small, rectangle connector that plugs into the circuit board, inside the starcom case...).


I looked at the circuit board and didn't see any pin numbers.

Since Starcom warrantied the circuit board, I have an extra set of these connectors. What I want to do is take the extra set of connectors, cut the circut board plug off the cable and solder on another PS2 connector (replacing the circuit board connector on the cable lead). I want to make an extension for the frame of the bike.

I guess I could use a volt meter to check for continuity on the other end of the cable and map it out, right?
<D>

 

[ShinySideUpAZ]

I am talking about the board side connector (Its a small, rectangle connector that plugs into the circuit board, inside the starcom case...).


I looked at the circuit board and didn't see any pin numbers.

Since Starcom warrantied the circuit board, I have an extra set of these connectors. What I want to do is take the extra set of connectors, cut the circut board plug off the cable and solder on another PS2 connector (replacing the circuit board connector on the cable lead). I want to make an extension for the frame of the bike.

I guess I could use a volt meter to check for continuity on the other end of the cable and map it out, right?
<D>

Yep, that'll work.

 

[dmulk]

Cool, thanks mark!

<D>