# TeleMetrum V2 vs BeeLine GPS (100mw)?

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#### billdz

##### Well-Known Member
Any thoughts on which of these is a better buy? The Bee is a bit cheaper. It has 100mw out, the TeleMetrum just 40mw. But the TeleMetrum supports dual deployment, the Bee does not. Which is more reliable and easier to use?
73, Bill

#### ChrisAttebery

##### Well-Known Member
I've got a Telemetrum V2 and I've been very happy with it. I've flown it to ~25k and had great signal strength with a simple 3 element Yagi antenna. If you have a Android tablet the app works great. If not a laptop works too.

Personally I wouldn't buy the 100mw BRB unless I was flying really high.

#### rms

##### Well-Known Member
I have both and flown both to ~23k. If your main goal is tracking, I would lean towards the BRB, wrap in close cell foam, stuff it in a nose cone, just works. Recover rocket, remove tracker and repeat in next rocket.

Greg

#### billdz

##### Well-Known Member
Thanks for the replies. Do I also need a TNC, like the Mobilinkd, or can I send the output from my HT directly to a laptop or tablet?

#### FredT

##### Well-Known Member
I have both and have several flights on each to ~20K with equal success. I'd expect the Bee to be more reliable at higher altitudes because of the more powerful transmitter, slower data rate, and (generally) better receiver.

The Bee is easier to mount because you can just stuff it into the nosecone. You have to design your av-bay around the TM2 to accommodate the longer antenna.

All that said, the flying experience with the TM2 is awesome. You get a lot more real-time data from the TM2, both on the pad and during flight. Mount a TeleBT on a 3-element yagi and pair it to your Android phone. It will speak to you during flight, telling you what the rocket is doing and where to look for it. Once on the ground, it'll guide you to it.

#### keithp

##### Well-Known Member
Do I also need a TNC, like the Mobilinkd, or can I send the output from my HT directly to a laptop or tablet?
Both BRB and TeleMetrum support APRS, which requires a TNC to decode the data. An HT, like my Yaesu FT1D with a built-in TNC is a great (if expensive) solution. You can use a software TNC in a laptop or tablet, but the resulting performance may not be as good, and will require an audio cable between the receiver and the laptop or tablet.

TeleMetrum also supports a digital telemetry which requires a custom receiver, either the TeleDongle (USB only) or TeleBT (USB and Bluetooth). Both of these work with Linux, Android, Windows and MacOS (although MacOS doesn't (yet) support Bluetooth to the TeleBT). These provide much more information during flight and recovery than is possible via APRS.

We also sell a small GPS tracker, TeleGPS, which is similar to the BRB except that it also talks to TeleBT/TeleDongle, but has lower power (around 10mW).

#### billdz

##### Well-Known Member
Hi Keith, I'm getting ready to place an order now. I see there's no Starter Kit with TeleBT, so for a full package I need to buy 1) TeleMetrum, 2) TeleBT, and 3) battery. Does TeleBT come with a USB cable? Am I missing anything? I already have an Arrow antenna.

#### ksaves2

Thanks for the replies. Do I also need a TNC, like the Mobilinkd, or can I send the output from my HT directly to a laptop or tablet?
Yes you need a TNC of some kind or diddle with the software decoders available that take the acoustic info off the earphone jack. If you are going to five figure altitudes and very far distances downrange, the higher powered trackers are at an advantage. Higher power = clearer signal that is more likely to be decoded.
If you accidentally knock a volume control or your computer is in a "bad mood" that day software decoding might not prove very easy to use in the field.

A Mobilinkd TNC can be used with any H/T but be aware that the receivers in the cheap Chinese H/T's are O.K. for voice but are really not as sensitive or as selective
as some of the higher quality APRS H/T's out there. If going to be doing a lot of APRS tracking, investing in a D72A, a used VX8GR (it's out of production), FT1DR
or the $Kenwood D74A. It depends upon what you want to do. If you just want to see an arrow on the H/T, any of the APRS H/T's (even the VX-8R) can do that. If you want to track on a computer, you want to see if the H/T in question can get the Waypoints out through a jack, port or B/T directly. The D74A at$600.00 (too rich for me) can get it out via B/T so any tracking app that can connect via B/T can track on a map for you. The D72A one can attach
Garmin 60Cs series and the old Etrex Vista mapping GPS devices for tracking on a map with a simple serial cable that attaches securely to both devices. This is a pure navigation app with no ability to save a flight, track or data. It will find the APRS tracked rocket and has never let me down when I don't want to diddle with a laptop or tablet.
The VX-8GR can use the same cable as the Kenwood to get the Waypoints (rocket position out) to a Garmin GPS with the big round serial port or the clip on the
Etrex Vista. The FT1D I don't think one can get the waypoints out of the device as easily but perhaps Keith may comment. I believe he tracks by using the
screen on the FT1D whereas I like to see a map.

Some folks use Baofengs and Mobilinkd TNC with Android devices but you have to set the volume on the H/T for accurate decoding and not touch it or you screw up the settings. Again, this combo might fail under the extremes of range. I've heard local radio stations coming in from the broadcast band faintly when I have
my Baofengs on the 2 meter and 70cm bands. Anything that uses a USB cable can get torn free from their respective devices easily.

If looking at an APRS H/T go to the manufacturers site and look at the manuals and see what means there is to get the waypoints out of the rigs in realtime.
A lot of the early Yaesu stuff like VX-8R's and DR's couldn't do that so stay away from those rigs unless one would be happy with an arrow on a the compass

Kurt

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#### billdz

##### Well-Known Member
Thanks for the replies. I ended up buying a TeleMetrum and TeleBT, seems most convenient and gives me the opportunity to try dual deployment in the future. And most importantly, the ground station talks audibly, that just seems cool. Can't wait to get it and try it out.