General Questions
Are there any concerns regarding the battery?
YES: Lithium poly batteries can be destroyed if overcharged or over discharged.
Always use an appropriate charger. NEVER discharge below 3 volts. Even though
the BeeLine Transmitters have a low voltage shutdown feature, the battery can
still be over discharged. Always turn the transmitter off when not in use.
Why do I need an amateur (ham) radio license?
The radio spectrum that the BeeLine transmitters utilize is regulated by the
FCC. The FCC requires that you be a licensed amateur radio operator to transmit
on these frequencies. While there are unregulated frequencies in this band
(433.92 Mhz, for example), the power limitations are too low to be usable.
What frequency should I use?
As a licensed amateur radio operator, you are free to use any frequency in the
70cm band. Please consult the ARRL band plans for recommendations and
restrictions. You may want to avoid repeater inputs/outputs and the weak signal
areas, especially in populated areas.
Where should I put my BeeLine?
The BeeLine Transmitter should be treated like any other piece of sensitive
electronics. The circuit board can withstand very high G flights, but is not
potted. The best place to put your transmitter is in the nosecone or a payload
bay. Simply wrap in bubble wrap and jam it in! Close proximity to altimeters
should be avoided due to concerns of RF from the transmitter adversly affecting
other electronics. Attaching directly to the shock cord is not recommended,
unless the transmitter is enclosed in some protective container, like another
piece of smaller diameter airframe tubing.
What about composite airfraimes?
Carbon Fiber and metal will block RF signals. Phenolic, cardboard, fiberglass
and other composites are OK.
How long does the battery last?
That depends on the transmitting parameters programmed into the BeeLine. With a
10% duty cycle (.5 seconds on, 4.5 seconds off) and 10 minutes between call sign
transmissions, a new, fully charged battery will last for more than 48 hours.
Can I use my own battery?
Yes. Any battery providing at least 3.2V and not more than 9V can be used to
power the transmitter. The supplied lithium poly battery has a fully charged
voltage of 4.25V, and should not be discharged below 3.2V
Can I use my own battery charger?
Yes, but it must be specifically designed to charge single cell
lithium polymer batteries.
What's the range of this transmitter?
That depends on number of things such as quality of the receiver, gain of the
antenna, and terrain. This transmitter has been tracked from 10 miles out using
a handheld ham receiver, and 20 miles using a more sensitive mobile rig and
larger car mounted antenna. The signal was clearly hear for the duration of the
N2N flight to 40,000 feet. The most important variable is terrain. At 433 Mhz,
RF waves don't 'follow' the ground well, and are easily blocked by small hills.
What kind of serial cable should I use?
The serial adapter is designed to plug directly into a standard DB-9 serial
port. If you use a cable, make sure it is a straight through extension cable,
and not a 'null modem' cable, or other kind of cable that swaps pins. Using the
wrong cable will result in timeouts, and may damage the serial adapter.
Are kits available?
No. Only fully assembled boards are offered for sale.
Can the BeeLine transmit telemetry data?
No, you need a BeeLine GPS transmitter to transmit data packets.
How do I program my BeeLine Transmitter?
You need to download the BeeLine Communicator. The latest version is
http://www.bigredbee.com/docs/beeline/beeline.zip
Can the BeeLine transmit on the 2 meter band?
No. The standard configuration supports the 70cm band. Custom builds can support
any frequency between 300 and 900Mhz.
What kind of antenna should I use?.
1) Build your own: http://www.nr6ca.org/70cmyagi.html
2) Buy one, I recommend this: http://www.arrowantennas.com/440-7ii.html
3) Or, for base operation, I have this one (not a directional yagi):
http://www.rfparts.com/diamond/x30a.html
Does the programming software run under Linux?
No, but one customer has reported that it worked fine using a windows emulator,
WINE version 0.9.17, with good results.
BeeLine Transmitter
How big is it?
The BeeLine Transmitter (B1) is .88" wide
x 1.725"
long.
The BeeLine MP Transmitter (B6) is .79" wide x 2.05" long
How much does it weigh?
xx.x grams
BeeLine
GPS
How big is it?
The 70cm BeeLine GPS is 1.225" wide
x 2.865"
long.
The 2M High power GPS is 1.255" wide x 3.635" long
