Originally Posted by KillerCut

we talked about that before. Its more trouble than its worth... the beacon works very well already, adding gps would make it bigger, shorter battery life, etc, etc....

I think that discussion was regarding using a data transmission, but what about simple morse code? Maybe it would only send out the morse code GPS position once per minute, or every 10 minutes. It would still send out the normal 3 beacon tones ever 4 secs, or however set. If you don't know morse code, you could record it and play it back slowly to decode it. There are online apps to translate as well. To make the morse code shorter, just the last digits (minutes and seconds) would be transmitted.
My DOSD has a GPS pass through so I wouldn't need to buy another GPS unit, they would share.
Peter, does this idea have any merit?

Originally Posted by kempo

Hi Peter, i've just made a paypal payment for a no vox RF beacon(i specified that i will use binatone walkie talkies).

Can you please check your Paypal ?

Are you selling also 1s battery for the beacon ?

Thank you.

thanks ! will ship tomorrow
1s 300mAh included
the ebay radio you linked sure will work

Originally Posted by fmkit

thanks ! will ship tomorrow
1s 300mAh included
the ebay radio you linked sure will work

Thank you.

Originally Posted by fmkit

sure,
btw I have pair of exact same looking radios, Motorola with Uniden PCB inside

ebay has many radios w/ Li-Ion batteries and SMA
My saved search

I got my Motorola Walkabouts today, wow they are tiny!
How do I mod it to add an sma connector? The antenna is a single coiled wire. Where does the ground wire of the sma connector get soldered to?

Originally Posted by iskess

I got my Motorola Walkabouts today, wow they are tiny!
How do I mod it to add an sma connector? The antenna is a single coiled wire. Where does the ground wire of the sma connector get soldered to?
Attachment 5027437Attachment 5027438

An excellent question! I also am using these radios. If I can use a directional antenna to locate the beacon, that would be great!

Hector

They use 1 wire because the antenna is Supposed to be a lot longer than they can actually use (or that anyone would want to carry). Hence, they dont need to ground any part of the antenna. If you want to, you can just solder your active pin for the sma connector and secure the sma connector with epoxy or something. The

Originally Posted by KillerCut

They use 1 wire because the antenna is Supposed to be a lot longer than they can actually use (or that anyone would want to carry). Hence, they dont need to ground any part of the antenna. If you want to, you can just solder your active pin for the sma connector and secure the sma connector with epoxy or something. The

Your message got cut off, please complete. Are you saying that the sma ground doesn't need to be attached to any part of the circuitry? It seems like it wouldn't make a very good directional antenna this way.

Originally Posted by iskess

Your message got cut off, please complete. Are you saying that the sma ground doesn't need to be attached to any part of the circuitry? It seems like it wouldn't make a very good directional antenna this way.

Just ground it to any ground on the unit near the signal wire. All the grounds should be common.

ohh if you will use a directional antenna then by all means ground it. There are a lot of ground points on the circuit boards... I thought you would use the stock rubber duckie or something similar...

Originally Posted by slowjett

Just ground it to any ground on the unit near the signal wire. All the grounds should be common.

I'm not sure that the antenna ground is the same as the other grounds.
I remember Alex (IBCrazy) was recommending creating a dipole for a 72mhz RX by sending the RX antenna down one wing, and the a ground down the other wing. I asked him if I could just use a black servo wire for the antenna ground wire, and he said its not the same. I would have to find the antenna ground pin on one of the chips and harvest it from there. I didn't know how to find this, so abandoned the project. I find myself in a nearly identical predicament now.

Thats because you would have a large piece of the active element exposed, and if you use servo wire as ground, your active element will still be exposed, you must use antenna cable.

Originally Posted by KillerCut

Thats because you would have a large piece of the active element exposed, and if you use servo wire as ground, your active element will still be exposed, you must use antenna cable.

You misunderstand. The whole antenna was supposed to be exposed, as it always is with a 72 MHz RX. The plan was no different than a normal 72 MHz RX antenna attached to a wing, except there was to be an equal size ground antenna wire in the other wing. Just a giant dipole the size of the wingspan.
Anyway, back to the point, how does one find the antenna ground on the PCB.
Peter, chime in here oh master guru.

I've read posts like some Australian guy pointed Yagi to beacon that was 7km away(he had to climb nearest mountain 1st) and such . After using the beacons for few years I'm sure no mods needed, compact walkie-talkie is all you need. In extreme situation place walkie-talkie onboard EZ* or SW and take it up 300m circle 2km radius - way more effective compared to pointing Yagi while at ground level.
I made digital long lasting beacon with LCD RX a year ago, turned out analog walkie-talkies atleast 20db better sensitivity, I had to put aside "advanced" system cause primitive 3 fading tones was practical and simple, keep your radios unmodified.Invest into video RX Yagi, they're smaller at GHz.and while searching at near range more useful than UHF beacon.

Originally Posted by iskess

You misunderstand. The whole antenna was supposed to be exposed, as it always is with a 72 MHz RX. The plan was no different than a normal 72 MHz RX antenna attached to a wing, except there was to be an equal size ground antenna wire in the other wing. Just a giant dipole the size of the wingspan.
Anyway, back to the point, how does one find the antenna ground on the PCB.
Peter, chime in here oh master guru.

ohh, I dont see a problem with that. Maybe Ibrazy didn't understand you. I think the only issue would be that you would probably need to keep the ground wire perfectly straight or something...

Originally Posted by joel0407

This thing is awesome. I tested mine this weekend, just past. We put it a couple of feet of 30mm square, white conduit to partly look like a foam plane and then had a mates father hide it.

We out of town and he came back to tell us it was within 20km, good luck. He didn't have much faith in us or the beacon.

We went to the highest point and picked up 1 scratchy tone with a yagi antenna. We headed in the direction with the UHF radio on in the car (Trucker CB for those in the US). 1 tone turned to 2 and then 3. From this point we disconnected the antenna and kept going. We finally got down to about 10m and then we just searched around in the grass and found it. It took about 20 - 30 minutes in total.

GPS distance from the high point to the beacon was 6.64km.

I doubt I will loose a plane again.

Not quite 7 km but I was close and have no doubt it would make more than 7.

I'm going flying this morning but I can post pics of my Yagi and Radio when I get back.

Happy Days.