# Big Red Bee GPS Tracking Rig

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Noooo!!! Don't waste the chicken! Barbeque it, instead! Gosh, man... have you no humanity??????

Two things pop into mind (it's been a long day administering the TAKS tests to the kdidies, today, so their brains and mine are both about mush!):

1. does your laptop have a LINE IN to go along with the MIC IN? The levels coming out of the scanner are bound to be too hot for the MIC IN, even at the lowest setting of the speaker output.

2. Might be getting some additional distortion due to impedance mismatch. Assuming the speaker output is 8 ohms, the LINE IN should be about 600 ohm, and the MIC IN is likely to be about 10K ohms. An audio step up transformer (8 to 600 ohms) might work if you can find that LINE IN jack. Radio Shack has some that should work.

Back in the early days of PSK31 when a lot of folks decided they wanted to try that "new" mode, they just plugged the speaker into the mic jack on the sound card with predictable results. Most have found the need for an impedance match, and I think that's going to be one of the answers for you, as well.
No, the laptop just has a mic input. In the Windows microphone settings, however, I turned the microphone boost down to zero, after which I can put the scanner output volume mid-range without any clipping. Before that, I had to turn the scanner output down to almost zero to avoid overdriving. The agwge o-scope plot of the noise does not get maxed out, and during transmissions the scope magnitude is about half of the range. I suspect that instead of making 2 hardware ports, they just made the microphone amplifier software-controlled.

Maybe the step-up transformer would help. I'm not familiar with those, though.

#### Sandy H.

##### Well-Known Member

You probably don't want to add another component to the mix, but I have a few external sound cards that run from USB. There are line level inputs etc. I used to play with speaker building and one of the tasks was to build a measurement rig. The reason I have a few of these devices is that latency was a real issue when trying to take measurements for the FFT. So, they do what they should, just not to the level required for that type of analysis.

If you want to give one a try, I can mail it out to you. I haven't used it in years, so its no bother.

Sandy.

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
The Yaseau doesn't interface with an external GPS or laptop, though, and the Kenwood, if it keeps the functionality it had in the previous version, will, which might be important to some folks (like me).
Not sure what your need is for the external connection, but one thing the VX-8GR does do is distance and bearing to the beacon it's receiving.

That keeps me from needing to tie the radio in to my GPS. But, depending on what you want the connection for, that may not alleviate the need.

-Kevin

#### n5wd

##### Well-Known Member
Not sure what your need is for the external connection, but one thing the VX-8GR does do is distance and bearing to the beacon it's receiving.

That keeps me from needing to tie the radio in to my GPS. But, depending on what you want the connection for, that may not alleviate the need.
Kev,

That allows you to get distance and bearing, but you can't display that waypoint on a topo map, or a geo map to see where it actually is in relationship to other things, unlike what you CAN do on a handheld GPS unit. That's the reason for the feed from the HT to the GPS. Some folks want that ability, others don't. I'd like to have it (that's why I'm waiting for the Kenwood product to poke it's head out of the incubator). Sometimes it's nice to see that you need to walk AROUND the lake instead of trying to walk THROUGH the lake! :shock: :blush:

Wayne

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#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
That allows you to get distance and bearing, but you can't display that waypoint on a topo map, or a geo map to see where it actually is in relationship to other things, unlike what you CAN do on a handheld GPS unit. That's the reason for the feed from the HT to the GPS. Some folks want that ability, others don't. I'd like to have it (that's why I'm waiting for the Kenwood product to poke it's head out of the incubator). Sometimes it's nice to see that you need to walk AROUND the lake instead of trying to walk THROUGH the lake! :shock: :blush:
It would indeed work for that; my issue is that I only have two hands, and trying to hold the Yagi, the radio and the antenna gets cumbersome. I don't like the idea of using long cables to attach things to a radio on my belt, either, as they're just likely to get caught on something.

To each their own; everyone has their preferred way of doing things.

-Kevin

#### n5wd

##### Well-Known Member
It would indeed work for that; my issue is that I only have two hands, and trying to hold the Yagi, the radio and the antenna gets cumbersome. I don't like the idea of using long cables to attach things to a radio on my belt, either, as they're just likely to get caught on something.

To each their own; everyone has their preferred way of doing things.
True dat. But, remember, once you've got the LKP, you don't need to hear the APRS signal anymore - it's not going to be changing, unless like I mentioned before, it landed in the backseat of a Corvette convertible going down the highway. If you get to the indicated LKP and you don't see the rocket, then fire up the HT again with the rubber ducky.

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
True dat. But, remember, once you've got the LKP, you don't need to hear the APRS signal anymore - it's not going to be changing, unless like I mentioned before, it landed in the backseat of a Corvette convertible going down the highway. If you get to the indicated LKP and you don't see the rocket, then fire up the HT again with the rubber ducky.
Easier than that -- treat it like a directional beacon.

-Kevin

#### n5wd

##### Well-Known Member
Easier than that -- treat it like a directional beacon.
Huh????????? Splain?

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
Huh????????? Splain?
If you get to where the GPS last said it was, and you don't see it, whip out the Yagi and start fox hunting.

-Kevin

#### n5wd

##### Well-Known Member
If you get to where the GPS last said it was, and you don't see it, whip out the Yagi and start fox hunting.
Ah! Gotcha, but have you tried to DF an APRS squirt? Not easy, especially if you've got the Beacon Time set to 1 minute. Again, though, if you can hear the signal, you should be able to decode the APRS data (which might be different than the LKP) and adjust course accordingly.

#### n1lul

##### Well-Known Member
Kev,

(that's why I'm waiting for the Kenwood product to poke it's head out of the incubator).

Wayne

Last I heard from the folks at HRO was that the new Kenwood will be at Dayton to see, but not touch.

I am still drooling over the VX-8GR

Kev,

That allows you to get distance and bearing, but you can't display that waypoint on a topo map, or a geo map to see where it actually is in relationship to other things, unlike what you CAN do on a handheld GPS unit. That's the reason for the feed from the HT to the GPS. Some folks want that ability, others don't. I'd like to have it (that's why I'm waiting for the Kenwood product to poke it's head out of the incubator). Sometimes it's nice to see that you need to walk AROUND the lake instead of trying to walk THROUGH the lake! :shock: :blush:

Wayne
A GPS application on my iPhone takes care of the mapping part. If I get the coordinates, I can enter them into the mapping application and figure out the best way to get there. I like the idea of being able to get a new GPS update after I get in range again, in case it goes over a ridge, or in case someone picked it up after I left my laptop in the car or the camp. I was tracking Chris LaPanse's rocket once, and was confused by the way the signal seemed inconsistent when we were trying to get a bearing. It turned out that it had landed in the road and someone picked it up and was bringing it back for us!

#### n5wd

##### Well-Known Member
A GPS application on my iPhone takes care of the mapping part. If I get the coordinates, I can enter them into the mapping application and figure out the best way to get there.
Ya know, I keep forgetting that my Iphone does have the mapping (along with satellite imagery) available. Duh!

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
The Yaesu VX-8GR is now shipping -- I received a notification from GigaParts yesterday that mine is on the way.

I should have it on Monday.

-Kevin

#### n1lul

##### Well-Known Member
The Yaesu VX-8GR is now shipping -- I received a notification from GigaParts yesterday that mine is on the way.

I should have it on Monday.

-Kevin
Sweet, keep us informed. I am torn between the VX-8GR and the FTM-350R APRS mobile.

#### n5wd

##### Well-Known Member
I should have it on Monday.
Don'tcha hate waiting? Full user report by Tuesday, please!

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
Don'tcha hate waiting? Full user report by Tuesday, please!
Dude!

If I could afford it, every order I place would be with overnight delivery!

Patience is a virtue I don't waste time on....

Unfortunately, Monday night I won't have much time to play.

-Kevin

Ya know, I keep forgetting that my Iphone does have the mapping (along with satellite imagery) available. Duh!
If you want to use maps when you're out of cell phone range, you'll need to spend $10 or so for a GPS application that has persistent maps, like motion-X GPS, which I have been happy with. #### n5wd ##### Well-Known Member If you want to use maps when you're out of cell phone range, you'll need to spend$10 or so for a GPS application that has persistent maps, like motion-X GPS, which I have been happy with.
Hmmm.. hadn't thought of that. No 3-G? Arggghhh!!

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
If you want to use maps when you're out of cell phone range, you'll need to spend \$10 or so for a GPS application that has persistent maps, like motion-X GPS, which I have been happy with.
Or use a GPS that lets you enter GPS coordinates into it.

I know I can do it with mine (GPSMap 76csx)

-Kevin

#### bigredbee

##### Well-Known Member
Sweet, keep us informed. I am torn between the VX-8GR and the FTM-350R APRS mobile.
Wait until the Dayton Hamvention (next week) -- Kenwood is expected to announce a replacement for the venerable TH-D7.

The Yaesu is a nice radio, but no PC interface for those that like that sort of thing.

-- Greg

#### jackman

##### Well-Known Member
I've noticed that the VX-8 says that APRS is "B band only". Can anybody say if that means 2m only or if it supports APRS on 440 as well.

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
I've noticed that the VX-8 says that APRS is "B band only". Can anybody say if that means 2m only or if it supports APRS on 440 as well.
APRS on 440 is supported. The B-Band refers to the second tuner -- if you want the radio to decode APRS for you, then you have to use the second tuner for it.

My VX-8GR is supposed to be delivered today; should have more info after playing with it for a bit.

-Kevin

#### n5wd

##### Well-Known Member
I've noticed that the VX-8 says that APRS is "B band only". Can anybody say if that means 2m only or if it supports APRS on 440 as well.
the VX-8 family of radios have two bands. They can be either VHF (2m) or UHF (70cm). You can set it up as V + V , U + V, V + U, or U + U. Whichever of the bands is in the "B" band slot is where you'll be able to do APRS. For most folks, that's probably going to be X (whatever your favorite band is) + V.

So, yes, it'll do 1200 and 9600 baud APRS on 440.

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent

Holy cow, this thing has a lot of features/functions! It's gonna take a while to figure out how to make it all work, but after 10 minutes of fiddling, and deciphering the manual, I've got it received and decoding APRS packets from the BeeLine GPS.

So, that's progress! Next up is to get the radio's GPS to get a lock and tell me where the BeeLine is.

-Kevin

#### jackman

##### Well-Known Member
That's great troj. Can you also say if it has digital PL in addition to analog.

Have fun!

#### n5wd

##### Well-Known Member
That's great troj. Can you also say if it has digital PL in addition to analog.
It has CTCSS and DCS. PL is, of course, available only on Motorola radios.:neener:

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#### jackman

##### Well-Known Member
Hopefully no one gets upset with me for taking this post and forum in a slightly different direction but my question does seem close to the spirit of this discussion.

I've been watching the movement toward Icom's DSTAR. In fact I just received the announcement from ARRL of a new DSTAR repeater system in Oregon where I reside. I'm concerned that someday Icom's DSTAR might become the "standard". In which case the purchase of a pricey Yaesu VX-8 might become orphaned due to its inability to work with DSTAR repeaters.

So what say you all? With there be 2 repeater types DSTAR and everyone else? Will I have to buy a new Beeline that works with a DSTAR HH? Kind 'a sounds like the old Mac vs PC thing to me or am I missing something?

#### n5wd

##### Well-Known Member
I'm concerned that someday Icom's DSTAR might become the "standard". In which case the purchase of a pricey Yaesu VX-8 might become orphaned due to its inability to work with DSTAR repeaters.
If you buy a Bee/GPS and a VX-8R, they'll work together until the Artic thaws and Kansas becomes an island. Why would you care what mode everyone else is using, if that's your only reason for buying the VX-8 or any FM handie talkie?

You're probably too young to remember when single-side band became THE way to modulate an HF rig, back in the 60's and 70's, but there are still, to this day, thousands (OK, maybe several hundreds) of folks who are using AM transmitters and not looking back. Just like there are thousands (no quivveling here) of folks who finger-talk using CW instead of grabbing a 2m FM transceiver to talk across town.

Even if DStar becomes four times as popular as it is, now, that will still leave 20 or more analog voice FM repeaters in most metropolitan areas to work the old fuddies.

So, if that's a concern, best give up buying a transceiver today, and just wait until tommorrow (which, of course, never comes...).

#### troj

##### Wielder Of the Skillet Of Harsh Discipline, Potent
Interestingly enough, the VX-8GR does have a serial port on it, and in the GPS menu, there's a COM port setting. You can set it for output, and send NEMA strings and waypoints.

So, it appears that the VX-8GR will indeed talk to a handheld GPS.

I don't have a cable with the right connectors, so I cannot play with it.

Edit Okay, I found it in the manual....

Output This item selects the output data type of the DATA jack. When this item is set to "OFF", the tranceiver does not output any data to the DATA jack.
When this item is to set "GPS," the transceiver outputs the GPS data (NMEA data: GGA & RMC) to the DATA jack.
When this item is to to "WAY.P," the transceiver outputs the Wayput data to the DATA jack.
-Kevin

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