midland 18 str weather radio strobe light

[moe]

Has anyone ever looked as to what is in the Midland model 18 STR Strobe light that is used in the weather radios?
I see these lights for around $15.00 plus shipping but a close look of the photo 3 LED's
I would like to try and build a light for my weather radio
Thanks
Moe
http://www.amazon.com/dp/B0002UB2K0/?ta ... 5lq3mh3j_e

[dacflyer]

looks like leds in series,
my weather radio has the same thing..i'll check into it more for you...
i am sure when the radio goes off..the output goes high.. 9V output i think..possibly flashing.

[Janitor Tzap]

looks like leds in series,
my weather radio has the same thing..i'll check into it more for you...
i am sure when the radio goes off..the output goes high.. 9V output i think..possibly flashing.

Your weather radio has a test button right?
Well....
The Plug Jack looks too be 1/8.
So get a 1/8 plug and stick it in to the flash option jack on the weather radio.
Put a 9Vdc Analog Volt Meter on too the 1/8 plug connections, and press the test button.
If the meters needle pulses up and down.
Then I say the Led's are driven by an internal flasher circuit in the weather radio.
If it is a steady voltage, then the flasher circuit is built into the LED package.

Note: Most auto-ranging DMM's aren't fast enough to handle a very fast voltage change {flash rate}.
Thus, if you have an older d'Arsonval movement VOM.
It can more readily see the pulsing voltage.


Signed: Janitor Tzap

[dacflyer]

ok, here is what i have found out...
i have the midland weather radio WR-300
the radio has a siren test button, but it will not activate the strobe. the strobe will only be activated when the radio actually goes off..
also. there is no power that comes from the strobe outlet...
the strobe outlet is only a switched output. no power output at all..
the strobe is battery powered. ( 18-STR )
i have a bicycle led light that looks exactly the same, has 2 AA batterys..
i actually changed the leds in it to brighter ones
so i am sure you could modify something.
i called MIDLAND they could not tell me the rated load of the strobe outlet.
they only told me that it is a switched output.

good luck...

[moe]

Thanks I will look into it, I also have a light that looks like the photo will try to wire it to a 1/8 inch plug and see it it works

[dacflyer]

ya, just wire the cord between B+ and the led +
let me know how it goes for ya

[moe]

just a up date wired the light as we talked about to a 1/8 inch plug. When I short the pins on the plug the light will come on.But when I plug it into the radio the light goes on about half as bright with no alarm.If I trip the alarm the light is bright. Any ideas ?
Thanks
Moe

[dacflyer]

try to reverse the polarity on the plug...might be leaking backwards thru the transistor
and are you using neg from battery or pos from battery?

try both and reversing polarity on the plug..
either way i am sure its a miswiring of some sorts..

let us know..

[moe]

dacflyer
That did it that for your help it works great total cost $4.00
moe

[dacflyer]

cool deal, how did you wind up wiring it ?

[moe]

I reversed the polarity on the plug as you said never thought of that thinking it was more like a switch
Thanks again

[dacflyer]

ok,, so the POS from your battery went to the tip and load to the gnd. part of the plug ?

[moe]

Yes

[dacflyer]

ok, cool...