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#1 ashdec87 Jul 12, 2010 04:48 PM

RF beacon question
 
Hi,

I just got the RF beacon from Fmkit. Does anyone know the default settings? How long till it starts transmitting, intervals, etc. Just want to test it out while I wait to get the LCD.. maybe I wont even have to wait if the times are reasonable.

thanks

ash

#2 Williwaw Jul 12, 2010 09:38 PM

I wish I could remember because I have one and have not been able to play with it yet. I know you can jumper a couple terminal to increase the the time until the beacon goes off. I want to say it is far less than 30 minutes in it's default config.
Edit: he was here today, maybe a pm can solve our question...

#3 ashdec87 Jul 15, 2010 11:55 AM

anyone else know?

#4 CoolBudz Jul 15, 2010 11:59 AM

sorry for the newb question but what does the rf beacon do?

#5 ashdec87 Jul 15, 2010 12:07 PM

lol its used to find your plane when/if it crashes. This particular one transmits on a UHF frequency that can be picked up by any cheap UHF walkie talkie. The stronger/more beeps you have, the closer you are to your plane.

#6 Daemon Jul 15, 2010 12:52 PM

When you ordered it, you should have specified what channel you wanted
and what interval you want it to transmit at. Only you would know what those
values are. At the specified interval it should beep 5 (I think 5, maybe 4) times, with each
beep decreasing in power. It'll also do its beep sequence when you first power it on.
If you're anywhere within about 30 yards though you're going to hear all 5 beeps unless
you're blocking the receiver antenna with your body, then you'll hear the first 4. It's
really meant for long range direction finding. Be sure not to power it with anything
more than 4V (wants a 1S lipo, but I can power it with a single large lithium button cell at 3V).

ian

#7 Williwaw Jul 15, 2010 01:39 PM

I think he is *also* asking about the default time at which point it starts transmitting at. PM sent since none of us can remember:)

#8 ashdec87 Jul 15, 2010 02:16 PM

ya I was mainly wondering when it starts transmitting..

#9 Daemon Jul 15, 2010 02:19 PM

The first series of beeps is immediately after you turn it on, as I said above.

ian

#10 fmkit Jul 15, 2010 02:19 PM

Quote:

Originally Posted by ashdec87 (Post 15525770)
Hi,

I just got the RF beacon from Fmkit. Does anyone know the default settings? How long till it starts transmitting, intervals, etc. Just want to test it out while I wait to get the LCD.. maybe I wont even have to wait if the times are reasonable.

thanks

ash

there are no default settings
if you don't remember TX channel activate scan mode (your 2-way radio)

#11 ashdec87 Jul 15, 2010 02:31 PM

oh ok, so there's no delay unless I program one?

#12 fmkit Jul 15, 2010 03:07 PM

Quote:

Originally Posted by ashdec87 (Post 15550787)
oh ok, so there's no delay unless I program one?

no, you have to have LCD to set delayed start

#13 ashdec87 Jul 15, 2010 03:26 PM

ok sounds good. LCD is in the mail..

#14 ashdec87 Jul 18, 2010 12:53 PM

one more question.

would using aluminum foil have the same effect as using my body to locate the signal? I was thinking I could use the foil to narrow 'view' of the antenna to focus the search area once I'm within 30m..

#15 fmkit Jul 18, 2010 01:43 PM

in ARRL Handbook they show paper tube covered with alum. sheet and walkie talkie tied with string to pull the radio in-out of tube. My own method is a bit different and way more precise: use whatever flat metal surface (alum. foil sheet or kitchen pot lid, if riding bike use air pump) and use it as reflector to make your 2-way radio directional. Imagine Yagi antenna , the metal object in your hand will act as rear most part of Yagi, notice the distance between vibrator(dipole) - should be around 13-15cm (FRS). With radio in one hand and metal object in other you can guess and point now directional antenna, try to locate minimum (easiest) when the radio muting last tone or you hear most break ups and move in opposite direction. With trained eye you can use whatever object outside(wall, metal fence, utility pole or your own car) to become reflector/blocker or amplifier. When I take bicycle ride with new RC receivers to test I stop at bus station about 1.2km from my house and stand with receiver in my hand next to the wall at certain distance and reception gets improved a lot because of reflected power. If you had chance to watch RSSI numbers while getting near walls that focus or reflect RF waves you'd get better idea what happen to radiowaves and next time use bare bones setup such as generic walkie-talkie with the beacon to find direction as fast as those with ton of equipment.
The beacon shipped with dipole antenna (thin teflon coated wires) , cut off black wire and loop the white wire thus reducing effective range - it will be easier to locate when near target.


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