Homemade radar screamer

[Blackbird]

Just for reference, I bought my screamer from the USA 2 years ago and love it to bits. It has 2 volumes, plus off and here is the link to price etc. http://www.motorcycleradar.com/produ...dar%20Screamer.

Its noise doesn't differentiate between laser or microwave threat but in all honesty, I don't think that this is any big deal as if you wait to figure out what it is before taking action, you're history anyway!

The earpiece which I had previously was good too, but I was forever unplugging myself or breaking the wire.

[Filter_nz]

I've made up a budget wiring diagram. It really is simply. You can add on whatever you like i.e LED's etc but might be a good idea to have them off a parallel circuit without the capacitor inline.
Once you've soldered or twisted all the wires shove it in a nice box with a hole for the piezo and audio lead (an perhaps a power lead) and use a sealant to waterproof. or not, whatever you perfer.

Check the attached pic. Peace out.

[The Stranger:Me]

I've made up a budget wiring diagram. It really is simply. You can add on whatever you like i.e LED's etc but might be a good idea to have them off a parallel circuit without the capacitor inline.
Once you've soldered or twisted all the wires shove it in a nice box with a hole for the piezo and audio lead (an perhaps a power lead) and use a sealant to waterproof. or not, whatever you perfer.

Check the attached pic. Peace out.

Is it just me, or is that a little different to your photo - photo 1 in the first post?

[Filter_nz]

It's basically the same.

1) I added a fuse after I hard-wired it to the bike's 12 batterty instead of a 9v battery.

2) Battery postive terminal now goes into the relay first rather than the piezo, this in theory should minimise any leakage / battery drain which I experienced.

Another point to note, the yellow wire in the orginal pic doesn't actually connect to anything and never did however the picture makes it appear to.

[The Stranger:Me]

It's basically the same.

1) I added a fuse after I hard-wired it to the bike's 12 batterty instead of a 9v battery.

2) Battery postive terminal now goes into the relay first rather than the piezo, this in theory should minimise any leakage / battery drain which I experienced.

Another point to note, the yellow wire in the orginal pic doesn't actually connect to anything and never did however the picture makes it appear to.

Thanks, built as per your original photo. Got that on the yellow wire already.
Initial test is good, will see how it goes tomorrow.

[SixPackBack]

I've made up a budget wiring diagram. It really is simply. You can add on whatever you like i.e LED's etc but might be a good idea to have them off a parallel circuit without the capacitor inline.
Once you've soldered or twisted all the wires shove it in a nice box with a hole for the piezo and audio lead (an perhaps a power lead) and use a sealant to waterproof. or not, whatever you perfer.

Check the attached pic. Peace out.

Shit hot! removing the cap and Piezo and adding an LED will give an in helmet [discrete] way to be 'notified'

[The Stranger:Me]

It's basically the same.

1) I added a fuse after I hard-wired it to the bike's 12 batterty instead of a 9v battery.

2) Battery postive terminal now goes into the relay first rather than the piezo, this in theory should minimise any leakage / battery drain which I experienced.

Another point to note, the yellow wire in the orginal pic doesn't actually connect to anything and never did however the picture makes it appear to.

Tried it today.
It works fine, but not loud enough for an old bastard.
Any chance you can modify it to electrify some nipple clamps for me?

[Filter_nz]

haha! sure thing!!
The piezo I used is 9 -16v from memory and your using a 16v cap so basically feeding it at 16v regardless of the battery size used....At least for the inital beep. If you radar were to put out a solid tone, (which the Escort x50 or Bel rx65 do not) you'd get a loud 16v beep to start with and once the cap was drained it would drop in volume to the power level of the battery. In normal operation the cap will charge up between beeps.

For more volume you could use a high voltage cap (but may not recharge fast enough between beeps) and over-drive the piezo or switch to a different piezo. The one I use is 85db, I've seen them right up to 130db.

I tested mine in the car and it nearly blew my ears to bits.

[Jantar]

haha! sure thing!!
The piezo I used is 9 -16v from memory and your using a 16v cap so basically feeding it at 16v regardless of the battery size used.........

Unless capacitor design has changed markedly in the many years since I studied electronics, the capacitor will only charge up to same voltage as the source feeding it. So if your battery voltage is 14V feeding into a 16V capacitor, the charge in the capacitor will still only be 14V maximum.

[Matt Bleck]

awesomeness

[Filter_nz]

Jantar your correct... had to think for a bit.
In theory the piezo should get dimmer until the cap is fully charged. Once fully charged the piezo should stop. If you then bridge out the battery (replace the battery with a piece of wire) the cap will release it charge.

However in my budget curcuit the piezo never stops for some reason (usually this would indicate an AC current). All I know is it works and thats good enough for me Although I may redesign it later correctly.

[Jantar]

...However in my budget curcuit the piezo never stops for some reason (usually this would indicate an AC current). All I know is it works and thats good enough for me Although I may redesign it later correctly.

It is a psuedo AC current, just a square wave, not a sine wave. I can see some improvements that can be made, and if I have time I'll make up the circuit and take some measurements.

[Revit]

It is a psuedo AC current, just a square wave, not a sine wave. I can see some improvements that can be made, and if I have time I'll make up the circuit and take some measurements.

That would be great

[Filter_nz]

That would be great

In short, the cap should be in parallel with the piezo not in series.

Ineffect the beep from the radar will trigger/close the relay, in turn this will sound the piezo and charge the cap (if in parallel). When the beep from the radar stops the relay will open however the piezo will still sound as the cap will sustain it.

The trick will be selecting the correct cap size so the piezo isn't susatined for to long as you may end up with a solid tone.

You could of course remove the cap altogther however when I did this the beep was so quick it was little more than a churp which I missed when on the bike.

[alanzs]

If you're not up to making one, I have one for sale in the trading section.... Saved my ass more times than I can count. I'll let it go for $30 plus $5 shipping. A bargain...

Radar Screamer USD RRP $99.95

This is for anyone with a radar detector on their motorcycle. This mounts easily and emits a 108 decibel PIERCING SCREAM when your radar detector gets a radar signal. You can EASILY hear this AT ANY SPEED. I had it on my Hayabusa, so I know.

The Screamer includes:

* A special interface module drives a 108 dB piezo beeper. Includes 3-position low volume/mute/high volume control switch.
* Epoxy Sealed interface module (54 x 35 x 15 mm) with control cable and audio cable with 2.5 mm audio plug [3.5 mm plug available for the Passport 8500]
* High intensity Piezo beeper (58 mm dia. x 32 mm high) with cable and connector
* Silence switch with cable, connector and mounting bracket. Now with High/Low volume and mute settings
* 12Vdc supply harness with in-line fuse holder and connector

* Includes everything in picture (1st one is from their from website) except Velcro, manual and high/low switch is black, not orange. See other photo I took. Instructions are available free online.
* Super simple to install. I can do it and I am no gearhead.

Used - excellent condition

Check it out on their website, where they have diagrams as well.

http://www.motorcycleradar.com/products_pg2_4.htm# Radar%20Screamer