Anyone know anything about RF?

[f0xy]

at a place that i work they have a entry/exit bollard system. the code to get out changes every day, 4 digit pin. alot of the time i forget and have to end up going back, parking up, and back inside to get it...

they gave me a little blip thing, lets you press the button and the barrier will go down if you're waiting.. no need for a code.

the blip has stopped working, and the company dont have anymore.. so i phoned the company who manage the barrier and they refuse to give any more out...

so i thought, it can only be a radio signal setting it off, RF maybe??

if so, is there any way i can find out the frequency that triggers the barrier?

cheers.

 

[Andy_con]

why dont you try find out whats wrong with that one???

they dont just stop working

 

[f0xy]

well, i changed the battery, it worked once after that, i took it apart and one of the electrical bits had come off, was either a resistor or transistor i dont know.. still flashes but dosent transmit i dont think

 

[Andy_con]

well simple repalce the bit that came off

 

[biojo]

post a pic of the part that came off some one will know

 

[f0xy]

but i dont know which pins on the back it came from... on the back of the pcb there are tons of little pins, few resistors and thats it on that side, so ive got no idea where it would go?

any way i can get/make a variable frequency transmittor and do it by trial and error?

 

[biojo]

well if u look at the resister it should have stripes to indicate which one it is, then simply goto work hold the risister against the solder points u think it should be on and press button , if it works solder back to there

 

[BrianR]

I think you will find there is a code encrypted on the signal, so just finding the frequency isn't going to help you.

If you can beg, borrow or steal a frequency absorption meter or a Grid dip oscillator, you can check the RF output, but you wont be able to read the code.
I have a R&S analyser that will do it but its a huge piece of kit.

Don't you know any Ham radio operators, they need to have a means of checking the output from their equipment its a condition of their licence.