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APRS lunch flight 4/17/08

Sam Buchanan

been here awhile
For anyone interested in watching an APRS flight in real time, plans are to launch N399SB from DCU about 11:30 CST for lunch at PLR. You can watch the 35 minute flight at this link:

http://aprs.fi/?call=N399SB&mt=m&z=10&timerange=3600

If you are not familiar with Google maps, here are a few pointers:

The map can be panned by holding down the left mouse button and dragging the map. Don't use the mouse wheel unless you want to see the map be rapidly zoomed.

When the cursor is over the map, zoom controls appear in the upper left corner.

You can switch views to satellite or terrain by using the buttons at the top of the map.

The current flight data will appear in the bubble pointing to the latest beacon dot, but you can click on any dot to get data.

On the return flight, if you want to also see the first leg of the flight, you may need to change "Show Last" to "3 hours".

Have a nice flight! :)
 
I'll be in the audience.

Sam,

How many did you get to join you and will I see multiple trackers?

Hope to draw my own line to Moon Town for Saturday breakfast.


Randy Hooper
 
WOW

Sam

I will be watching. Give me some pointers on what I need to tell my boss when my plane is done so I can go flying during lunch time. :D
 
For anyone interested in watching an APRS flight in real time, plans are to launch N399SB from DCU about 11:30 CST for lunch at PLR. You can watch the 35 minute flight at this link:

http://aprs.fi/?call=N399SB&mt=m&z=10&timerange=3600

Have a nice flight! :)

OK this is AWESOME! I'm watching it in Google earth so that I get the altitude reference and it is spectacular. Lets see he's at 3500 doing 160mph that will get you to lunch but quick!

THANKS!!!!
 
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Pretty amazing, Sam. I'm watching you fly right now. Screen refreshes about every minute.
b,
d
 
When Sam needs to ask for time off, he talks to himself! (He's self-employed.) :cool:

Yeah I figured that. Now the question is, looking at his speed is he going to tell us he was in economy cruise burning 6 gal per hour. You gotta love these planes. Aint no spammers going to do that.
 
Very Cool!
Watched your left downwind, base and final for 18.
I'm not much of a tech head but this is a must have for me.
 
Agreed, Bruce.

Anyone watching this as it happened was sold on the concept in about three minutes.

b,
d
 
Yeah I figured that. Now the question is, looking at his speed is he going to tell us he was in economy cruise burning 6 gal per hour. You gotta love these planes. Aint no spammers going to do that.

Back at the office after a hard day of labor.......... ;)

Well, actually it was about 65% power and 7.5 gph. :)

Thanks for flying along fellas. Your desk chair was riding a whole lot smoother than the RV-6 in the vigorous thermals......but I had a better view!

Anyone with an interest in APRS feel free to toss in any questions so we can get you up and running. Lots of good info in the APRS forum archives, too.

APRS is not just for experimentals, there are ways to make it work in certificated aircraft.
 
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Pell City. Great place to have lunch.

This is added motivation to pursue the self-employment option. :)
 
Pretty amazing, Sam. I'm watching you fly right now. Screen refreshes about every minute.
b,
d

Thanks Doug (taken the Tech exam yet?). My tracker is configed to send packets every 60 seconds except when SmartBeaconing kicks in during maneuvering flight.

Thanks for flying along! :)
 
Wow!

Thanks for flying along!

Sam,

I was along for part of the ride, and Wow! what a great bit of technology. I've read a good bit of past APRS posts but maybe you (and others) can answer a few questions:

1. I'm a past Novice licensee (about 30 yrs ago, KA7HZO) so I took an online practice test cold: 90 something % :) I'll try a few more then do it. Is there any downside to failing besides the fee and the time? The amount I prepare is a function of risk/return.

2. I'd like to do a wingtip install since I'll already have 2 belly whips for Comm. I'm thinking:
- J-pole antenna
- Micro Trak 300 xmtr / tracker
- Byonics GPS2
- tie into nav light circuit for power

a. Do I need the 12v regulator if I use ship's power via the nav light circuit?
b. How important is more power (should I go for 8 watts)?
c. How important would frequency agility (FA) be?
d. Is is worth it to save a buck by running a couple wires from a panel GPS to the tip so I don't need the dedicated GPS?
e. Is having the activation of APRS tied to the NAV light something you'd worry about?

I know that's a bunch of questions, but maybe others can join in and this would add to the knowledge-base (and put the most recent wisdom in one place).

Thanks,

George
 
Sam,

I was along for part of the ride, and Wow! what a great bit of technology. I've read a good bit of past APRS posts but maybe you (and others) can answer a few questions:

Thanks for flying in the back seat, George! Your reaction to seeing APRS in action for the first time is typical, it is indeed cool technology.

1. I'm a past Novice licensee (about 30 yrs ago, KA7HZO) so I took an online practice test cold: 90 something % :) I'll try a few more then do it. Is there any downside to failing besides the fee and the time? The amount I prepare is a function of risk/return.

I don't have a definitive answer for this, maybe experienced hams can chime in. I suspect if an exam was failed, you could pay another fee right on the spot and retest if you wanted.

But....if you are hitting 90% cold you aren't going to fail. :)

2. I'd like to do a wingtip install since I'll already have 2 belly whips for Comm. I'm thinking:
- J-pole antenna
- Micro Trak 300 xmtr / tracker
- Byonics GPS2
- tie into nav light circuit for power

That will be a very capable system, Pete Howell got good results with that setup.

a. Do I need the 12v regulator if I use ship's power via the nav light circuit?
b. How important is more power (should I go for 8 watts)?
c. How important would frequency agility (FA) be?
d. Is is worth it to save a buck by running a couple wires from a panel GPS to the tip so I don't need the dedicated GPS?
e. Is having the activation of APRS tied to the NAV light something you'd worry about?

A. No need for regulator if you use the MT-300. The MT-8000(FA) will need the Micro-Volt or regulated power.

B. Good question.....sorta like "should I prime my airplane?" :D
The 8w unit definitely is a high-performance little tracker. It is great if you have a marginal antenna or plan to be flying far from digipeaters or at low altitudes. I'm now using an MT-8000 even though I got good results with the MT-300. The 8-watter can be dialed down if you decide you want to run less than full power.

C. FA is not a factor unless you want to run your own private APRS net. I've heard there are some metro areas now running a secondary APRS freq but I don't have personal experience with them.

D. You would only need to run one wire since signal ground can be via airframe ground. Maybe the bonafide techies can tell us if there will be a problem with data voltage drop over that run. I doubt there would be a problem if the tracker was the only device connected to the GPS.

E. Not if you don't mind running the nav lights all the time. My tracker is on the strobe circuit.


I know that's a bunch of questions, but maybe others can join in and this would add to the knowledge-base (and put the most recent wisdom in one place).

Thanks,

George

Thanks for asking the questions, George. I'm sure there are others wondering the same things.

Happy tracking!
 
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Sam has it right.....

Hi George,

I have used a MT300 and a MT8000. My advice is to get the 8000 and dial it down as required.

I use the MT8000 with the Microvolt unit, GPS2, and the J-pole. We get great results up here in Minnesota. I run the unit at about 3 watts and know I have 5 watts in reserve if I ever need to dial it up - like this summer when we fly out to Montana.

I tapped into my LED nav light circuit. With a 50,000 hr life, I'll risk running the navs all the time - other than when in "stealth" mode.

Let us know if you have more questions.
 
Giddy...

Sam & Pete,

I am inexplicably giddy about this, and still a long way from having an airplane to install it in. I unpack my finish kit tomorrow morning and soon I'll be "under the canopy" for several months. Typical builder though, we do like our gadgets :)

Anyway, thanks very much for the information. I suspect I'll go for the 8000 with the regulator (that part is a bargain after all). Given that amount of power, what would you say to installing the unit behind the panel or under the seat and running coax to the wingtip for the antenna?

This would mean:
- I could program / re-program it w/o removing a wingtip
- I could more easily put it on its own switched power circuit
- I could very easily use the serial output of either one of my panel mounted GPS's.

I have plenty of conduit space, my antenna plan thus far is:
- Xpndr on belly aft of firewall
- Comm1 on belly under seat
- Comm2 on belly aft of baggage compartment
- Nav in one wingtip
- ELT behind canopy frame

I guess I have plenty of time to figure this out, and to get my Technician ticket. Are either of you using your license for any other radio work? Any suggestions for me to research re: use of 2-meter or other bands?

George
 
It Depends......

Sam & Pete,

I am inexplicably giddy about this, and still a long way from having an airplane to install it in. I unpack my finish kit tomorrow morning and soon I'll be "under the canopy" for several months. Typical builder though, we do like our gadgets :)

Anyway, thanks very much for the information. I suspect I'll go for the 8000 with the regulator (that part is a bargain after all). Given that amount of power, what would you say to installing the unit behind the panel or under the seat and running coax to the wingtip for the antenna?

This would mean:
- I could program / re-program it w/o removing a wingtip Yes
- I could more easily put it on its own switched power circuit Yes
- I could very easily use the serial output of either one of my panel mounted GPS's. Yes

I went with the self contained wingtip install b/c I am basically lazy. It was the easiest and least intrusive. I did not want to run more coax and had an easy power source to tap into. To be honest, I did not know if it would work and the complete install cost be an hour or two of time and was easily reversible. If it did not work - I would have not told any of you VAFinistas about it. :D OK, maybe I would have.....

If I was building from scratch, your plan sounds just fine. What Sam did is very cool too.

I have plenty of conduit space, my antenna plan thus far is:
- Xpndr on belly aft of firewall
- Comm1 on belly under seat
- Comm2 on belly aft of baggage compartment
- Nav in one wingtip
- ELT behind canopy frame

I guess I have plenty of time to figure this out, and to get my Technician ticket. Are either of you using your license for any other radio work? Not Yet

Any suggestions for me to research re: use of 2-meter or other bands? Google;) Tons of info on the net. Some sites even have incredible time-wasters called FORUMS......

George
 
Sam & Pete,

I am inexplicably giddy about this, and still a long way from having an airplane to install it in. I unpack my finish kit tomorrow morning and soon I'll be "under the canopy" for several months. Typical builder though, we do like our gadgets :)

Anyway, thanks very much for the information. I suspect I'll go for the 8000 with the regulator (that part is a bargain after all). Given that amount of power, what would you say to installing the unit behind the panel or under the seat and running coax to the wingtip for the antenna?

This would mean:
- I could program / re-program it w/o removing a wingtip
- I could more easily put it on its own switched power circuit
- I could very easily use the serial output of either one of my panel mounted GPS's.

I have plenty of conduit space, my antenna plan thus far is:
- Xpndr on belly aft of firewall
- Comm1 on belly under seat
- Comm2 on belly aft of baggage compartment
- Nav in one wingtip
- ELT behind canopy frame

I guess I have plenty of time to figure this out, and to get my Technician ticket. Are either of you using your license for any other radio work? Any suggestions for me to research re: use of 2-meter or other bands?

George

Giddy George, hold off on purchasing a tracker until you need it. Allen Lord (designer of the Byonics trackers) has let the cat out of the bag about a tracker he is considering that will have the 8 watt transmitter and regulated power supply on the same board. If you must have a tracker now, fine, get the MT-8000 and Micro-Volt. :)

My tracker is behind the instrument panel for all the reasons you stated. It is a short coax run to the bay beneath the left seat for the external whip antenna. If you want an external antenna and don't mind adding to the antenna farm, you could put COM 1 under one seat and the APRS antenna under the other. Push each one as far outboard as possible and everything should work fine.

I now have an APRS iGate running here in the home office. Earlier this week a stacked 5/8 wave vertical antenna went up on the roof of the house and I can receive beacons directly from my plane 75 miles away and port them to the internet. It's also my way of contributing to local APRS coverage. The iGate may eventually become a full-blown digipeater but there is no urgency since we have several digis in the area.
 
Tracker Design

I replied to the feedback from the Tracker folks and had asked for a single board Track with 8 Watts, Voltage Regulator and the option of built in GPS with embeded GPS Antenna for a easy Wingtip installation.
If you are going to use a panel mounted GPS for your tracker, it must support NMEA 0183 serial output format. Because of this a Garmin GNS-430, 530, 430W and 530W will not work. But most handheld do output the NMEA 0183 format.

Also, would it be possible to use a spare Com Antenna which I already have on the belly for the APRS transmitter. The frequencies are very close. I would expect some range loss, but just curious if it would work?


Ray Doerr
I was going to design my own board, but if they come out with this, I won't have to.
 
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I replied to the feedback from the Tracker folks and had asked for a single board Track with 8 Watts, Voltage Regulator and the option of built in GPS with embeded GPS Antenna for a easy Wingtip installation.
If you are going to use a panel mounted GPS for your tracker, it must support NMEA 0183 serial output format. Because of this a Garmin GNS-430, 530, 430W and 530W will not work. But most handheld do output the NMEA 0183 format.

Also, would it be possible to use a spare Com Antenna which I already have on the belly for the APRS transmitter. The frequencies are very close. I would expect some range loss, but just curious if it would work?


Ray Doerr
I was going to design my own board, but if they come out with this, I won't have to.


Ray, I'm not sure how much an advantage it would be in our application to have the GPS embedded on the board. Having the GPS receiver/antenna as a separate unit allows us to locate the tracker conveniently and still place the GPS where it can see the sky. Seems the embedded GPS would limit our options for mounting the tracker.

The APRS antenna element is ~3 inches shorter than the COM element [234/freg Mhz) x 12 = length in inches]. The Byonics tracker can reportedly handle up to a 20:1 SWR mismatch with no damage to the transmitter but I don't know if an antenna three inches too long will be within this threshold. I suggest trimming the spare COM antenna by three inches and you should have a great APRS antenna. This is assuming the COM antenna is a simple whip and doesn't have some sort of loading coil in the base. You can check to see if the antenna is "simple" by verifying the element is ~22 1/2" long. The inexpensive COM whip antennae available at Aircraft Spruce et al would make very nice APRS units when trimmed.

Of course the proper way to tune the COM antenna would be to borrow an SWR meter from a local ham and trim the antenna for lowest SWR at 144.39 Mhz.
 
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Altitude Matters

If you have people watching your flight real-time, warn them that the tracker will likely miss low altitude transmissions, particularly in remote areas. My brother was watching my flight into Page, AZ on Sunday with Terrain showing as the background. Immediately after I shut down the engine, I got a panicked phone call from him. He said that the data points had been periodic but stopped on final right where a rise in the terrain was shown on the map. That was the last data point. He thought I had hit the mountain! Make sure that real-time viewers understand that low power transmitters may miss some points. Now, if you've got a transmitter like Sam, where the lights dim when it fires up, you probably get all the data!!!:D:eek:

 
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If you have people watching your flight real-time, warn them that the tracker will likely miss low altitude transmissions, particularly in remote areas. My brother was watching my flight into Page, AZ on Sunday with Terrain showing as the background. Immediately after I shut down the engine, I got a panicked phone call from him. He said that the data points had been periodic but stopped on final right where a rise in the terrain was shown on the map. That was the last data point. He thought I had hit the mountain! Make sure that real-time viewers understand that low power transmitters may miss some points. Now, if you've got a transmitter like Sam, where the lights dim when it fires up, you probably get all the data!!!:D:eek:
I'm sorry this is horrible but ROTFL!!!!! :D The simple fact is that I could easily picture my mom or sister doing that.
 
Rick, I doubt that even if you had LEDs that you would have been looking at them on final at KPGA. Am I correct?

Plus, knowing that you have a GPS lock and a XMTR transmission says nada about reception by the APRS ground system.
 
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Now, if you've got a transmitter like Sam, where the lights dim when it fires up, you probably get all the data!!!

Rick, I doubt that even if you had LEDs that you would have been looking at them on final at KPGA. Am I correct?

Plus, knowing that you have a GPS lock and a XMTR transmission says nada about reception by the APRS ground system.

I think Rick was referring to the cabin lights dimming when the monster 8 watt tracker fires. :D
 
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8 watt Flamethrower

I think Rick was referring to the cabin lights dimming when the monster 8 watt tracker fires.

I always love that one....... as Allen says "May cause sterility in small mammals" or something to that effect;)
 
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I think Rick was referring to the cabin lights dimming when the monster 8 watt tracker fires. :D

I always love that one....... as Allen says "May cause sterility in small mammals" or something to that effect;)

I've got the antenna located under the pilot's seat.........:eek: ........ :D
 
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Gutter, this exit.

You guys took a perfectly innocent jab and went straight to the gutter!! I loved it though! Keep those ham sandwiches coming. :)

Back in the late 70s, I remember this guy I knew that had a 1,000 W amplifier on his radio in his car. He could hold a light (flourescent?) about 10 feet away and it would light up when he transmitted. Totally crazy, but I still remember it. In an RV, the skins would probably humm!! Is Allen still taking suggestions for the next generation??
 
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