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In helmet LED for Radar Detector, anyone made one?

Started by Bigbore4, August 29, 2008, 10:35:15 AM

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Bigbore4

OK I admit, I am cheap!

I want to build a hard wire LED to fit inside my helmet that will operate from the audio out jack on my detector (Passport 8500).  I mocked up pne this morning, 2.6 volt LED and a 330 ohm resistor.  It "works" but not very bright.  I'll need to do a better cludge to test it on buike, but I dont think it will be visible enough in daylight.

I looked at HARD, and besides the initial expense, it is a bit bulky and some other boards mention it's easy to forget to tun off and kill the battery overnight.

Anyone else look at building their own?  Post up a schematic!
Dave
96 M900         05 FJR         86 SRX6        
And a brand new Super Tenere coming in no one knows

MaxPower

#1
Alright bear with me, my electronics design is pretty rusty.

So you're not getting enough current from the audio out, could you use a simple BJT transistor with a 9V (or other) battery to supply the current to the LED?  Put the audio out on the gate to switch the transistor 'on' and 'off'.

I mention using the battery so you can have an all-in-one design that could maybe be stowed in the jacket (or even in the helmet somewhere?)
Nobody snuggles with Max Power. You strap yourself in and feel the Gs!
----------------
2003 M620i.e.

Capo



Capo de tuti capi

Bigbore4

Quote from: MaxPower on August 29, 2008, 10:46:57 AM
Alright bear with me, my electronics design is pretty rusty.

So you're not getting enough current from the audio out, could you use a simple BJT transistor with a 9V (or other) battery to supply the current to the LED?  Put the audio out on the gate to switch the transistor 'on' and 'off'.

I mention using the battery so you can have an all-in-one design that could maybe be stowed in the jacket (or even in the helmet somewhere?)

I want to stay to a simple, one hard wire rig.  Same as my ear bud, but visual.

I did find out that a lower current LED, the ones I have are 28mA if I remember right, and go to one around 10 mA.  I can't get to Aerostich from work, the IP (internet police) have the web stores blocked, but I bought a device there a couple years back.  Has 5 or 6 LED's, litle triangular thing plugs direct into the audio out.  Bright as hell but very directional.  It has no amp or power.  It's too big to fit in the helmet, and with all the moving around on the bike it is impossible to maintain the optimum angle to ensure visibility. Kicks butt at night though!

If I can track down the outfit that made that, I'll ping them, but I about wore out Google this morning and never hit that one.

Perhaps if I do figure this out I can make a buck or three?

Anyone else?
Dave
96 M900         05 FJR         86 SRX6        
And a brand new Super Tenere coming in no one knows

Bigbore4

Self serving bump to catch the folks coming home after the holiday!
Dave
96 M900         05 FJR         86 SRX6        
And a brand new Super Tenere coming in no one knows

scooby

Quote from: Bigbore4 on August 29, 2008, 11:35:25 AM
I did find out that a lower current LED, the ones I have are 28mA if I remember right, and go to one around 10 mA.  I can't get to Aerostich from work, the IP (internet police) have the web stores blocked, but I bought a device there a couple years back.  Has 5 or 6 LED's, litle triangular thing plugs direct into the audio out.  Bright as hell but very directional.  It has no amp or power.  It's too big to fit in the helmet, and with all the moving around on the bike it is impossible to maintain the optimum angle to ensure visibility. Kicks butt at night though!

If I can track down the outfit that made that, I'll ping them, but I about wore out Google this morning and never hit that one.

www.marcparnes.com/Visual_Alert.htm

I use one with my Passport 8500 x- works great...
What would ScoobyDoo?

Bigbore4

Quote from: scooby on September 01, 2008, 06:18:33 PM
www.marcparnes.com/Visual_Alert.htm

I use one with my Passport 8500 x- works great...

I have one.  I can't seem to get it positioned to grab my attention in daylight.  I was swapping email with Marc over the weekend.  He's gonna send me a couple of the really bright diodes he uses to play with.  I had a mock-up working this weekend, but need it brighter.

If I get this figured out it will be simple, and right in my peripheral vision.

Anyone else tried?
Dave
96 M900         05 FJR         86 SRX6        
And a brand new Super Tenere coming in no one knows

OverCaffeinated

This one should get your attention, but you did say you wanted to keep it simple, so it might not be your cup of tea. At least it's an all in one kit.



Link

Bigbore4

Quote from: OverCaffeinated on September 02, 2008, 10:18:11 AM
This one should get your attention, but you did say you wanted to keep it simple, so it might not be your cup of tea. At least it's an all in one kit.



Link


I should clarify, simple to use. 

I looked at these, they are easy to use after install, just put yir bucket on.

Violates my cheap gene's though.

Dave
96 M900         05 FJR         86 SRX6        
And a brand new Super Tenere coming in no one knows

nkryptit

Quote from: MaxPower on August 29, 2008, 10:46:57 AM
Alright bear with me, my electronics design is pretty rusty.

So you're not getting enough current from the audio out, could you use a simple BJT transistor with a 9V (or other) battery to supply the current to the LED?  Put the audio out on the gate to switch the transistor 'on' and 'off'.

I mention using the battery so you can have an all-in-one design that could maybe be stowed in the jacket (or even in the helmet somewhere?)

This would be my suggestion also, Maybe use one of those little coin batteries instead of a 9V to keep the bulk down enough to fit it in your helmet...could probably stick the transistor right to the battery, then silicone the whole thing, maybe tape it up nice...shouldn't be too much bigger than the battery and the led.

I don't see anyone getting enough current out of an audio jack without amplification to light an led.

Bigbore4

Quote from: nkryptit on September 03, 2008, 08:44:30 AM
<snip>
I don't see anyone getting enough current out of an audio jack without amplification to light an led.
<snip>

Marc Parnes did, www.marcparnes.com/Visual_Alert.htm, my only issue with his is I cant get it situated right in daylight, and it is a bank of 6 diiodes, too big to go inside my helmet.  But it is bright as hell and drives off of the audio jack only.

I plan to have this together for a trial during next weeks trip to Indy!
Dave
96 M900         05 FJR         86 SRX6        
And a brand new Super Tenere coming in no one knows

nkryptit

OK....So after looking at this www.marcparnes.com/Visual_Alert.htm I retract my first comment.

Another thought...Maybe they are using capacitors inside to provide a more solid current source...I'm trying to imagine what the schematic would look like...But from what I can tell, the current coming through your headphone jack at any instant isn't enough to give you a nice bright led.

Think of it like this,  The very beginning (first few milliseconds) of the BEEP that is coming from your detector is going to be charged up until the voltage differential over the capacitor is enough to make the led flash nice and bright.  So you'd have to find the right capacitor/transistor to form a sort of loop.

From the way the visual alert is described (the leds will blink faster and faster the closer you are to the source) it seems like this is how they accomplish it.  The more sound coming from the detector, the more time the cap will charge/discharge, until it would look like the led was staying on.