Practice Beacon Battery Options

IceNine · June 23, 2007, 04:41:03 AM

anyone found a decent alternative to paying $40 or more for a pointer beacon battery? Or even better built/found a battery that is rechargeable?

sardak · June 23, 2007, 04:56:53 AM

I own a practice beacon that runs on four alkaline C-cells. I've used another that runs on rechargeable batteries (C-cells I think, but not sure). One group has a beacon that can be powered by solar panels and can be turned on and off remotely using DTMF (touch tones).

Every beacon I've seen runs off cheaper alternative batteries once the original ones die.

Mike

IceNine · June 23, 2007, 04:58:04 AM

great any specs? I know there are options but have no clue where to start

SarDragon · June 23, 2007, 05:45:17 AM

I don't recall the battery specs, but if they aren't on the side, you'll need to use a voltmeter to check its output. That's assuming the unit is still working. A battery of sufficient voltage that will put out .75 A-hr will probably do the trick.

Al Sayre · June 23, 2007, 05:45:33 AM

All the pointer battery is, is 5 'C' cells soldered in series with a jack and some fancy foam packaging.

I went to Radio Shack and got 1 4-AA and 1 single AA holder, wired them together and soldered the battery jack to the new rig. I just replace the AA's after 36 hours and it works great. I've also seen a lantern battery used with the whole assembly mointed in an ammo can. The biggest thing is to save the jack from the pointer battery, clip it off so the leads are as long as possible. YMMV.

SarDragon · June 23, 2007, 05:50:24 AM

Update - info from the Pointer site:

The Model 6000 originally was assigned a 121.600 Mhz frequency. A retro fit to the new 121.775Mhz can be done at the factory. Also, for home made battery packs, we suggest a maximum of 8 volts for supply. A battery pack consisting of 5 alkaline "C" cells would supply 7.5 volts. Typical output signals from trainer units are of 150mw range at 7.5 volts supply. To achieve a simulated ELT with a broken antenna or low power, don't extend telescopic antenna or use 4 "D" cells to produce a 6 volt supply voltage.

Al was right on.

Al Sayre · June 23, 2007, 05:54:17 AM

Just think, all those years sitting in Electrical Engineering classes finally paid off!

SarDragon · June 23, 2007, 05:56:00 AM

Quote from: Al Sayre on June 23, 2007, 05:54:17 AM
Just think, all those years sitting in Electrical Engineering classes finally paid off!

That was just A-school info for me.

Al Sayre · June 23, 2007, 05:59:23 AM

Yeah I know. I learned more in BE&E, AVA-1, AFTA & AVIC-7 than I even came close to hearing about at college...

wingnut · June 23, 2007, 06:13:35 AM

Hey guys

I think we should all consider that the pointer is a FCC licensed transmiter, any alteration of the battery changes the output, changing the anttena may alter the frequency output, pay close attention to the details since altering the radio by an unlicensed techno-nerd and having the radio transmit off of the 121.775 is a federal crime. i talked to the fcc about this, we are allowed to use the ponter witout modification, this includes using the correct voltage for the transmitter. Too high voltage can actually alter the output frequency, too low can also alter the output. You should follow the guidelines in the CAP emergency services web page that give yo some great Ideas. Don't go in and start altering circuits unless your a qualified ham or you have your General radio operators license. Anything we do that is illegal reflects on all of us in CAP.

No wit that said check into some of the quik charge remote control car batteries, they have some that are about 7.2 volts and have rapic charge connections. Ponter wants your left N&% to buy a battery and it is good for only 30 hours of use.

SarDragon · June 23, 2007, 06:26:41 AM

See my quote from Pointer above. I doubt they would recommend an operating procedure that would cause an FCC violation. The frequency is Xtal controlled, so low voltage should only reduce the power output, the same as regular ELTs. Changing the antenna also will not affect the output frequency, only the radiation pattern, and the effective radiated power.

wingnut · June 23, 2007, 06:51:45 AM

Dave
Check with pointer, they told me it can change the frequency, I defer to them since the license for the production is in their court, I am not a layman when it come to this but we must be careful to not encourage any unauthorized alterations of these devices. in fact any adjustment can only be made ny a 'Licensed technician, anyone else 'Watch out" we are asking for trouble. Thats all I am saying, ET may be able to phone home with a record player.

sardak · June 23, 2007, 07:06:04 AM

Quote from: wingnut on June 23, 2007, 06:51:45 AM
in fact any adjustment can only be made ny a 'Licensed technician...
Quote from: wingnut on June 23, 2007, 06:13:35 AM
Hey guys
I think we should all consider that the pointer is a FCC licensed transmiter...altering the radio by an unlicensed techno-nerd... Don't go in and start altering circuits unless your a qualified ham...

Having just a ham license isn't enough to be that licensed tech.
Mike

Al Sayre · June 23, 2007, 07:49:07 AM

If you compare voltages, you'll find that both AA and C are nominal 1.5VDC the main difference is the endurance. The 5 C cell pack will run for about a week, whereas the AA will only last for about 36 hours...

wingnut · June 23, 2007, 09:15:02 AM

Ham guys cannot modify commercial radios,an elt simulator is considered per FCC regulations as a 'Subpart P, and utilized only as defined in PAR. 87.52(e) of the FCC rules and Regulations.

It is in fact a Radio Station as defined by the FCC and th FAA

IceNine · June 23, 2007, 12:48:44 PM

thanks for all of the info ladies and gents