apogee and main ejection charges. All Altus Metrum products are
designed for use with single-cell batteries with 3.7 volts nominal.
</para>
+ <para>
+ The battery connectors are a standard 2-pin JST connector and
+ match batteries sold by Spark Fun. These batteries are
+ single-cell Lithium Polymer batteries that nominally provide 3.7
+ volts. Other vendors sell similar batteries for RC aircraft
+ using mating connectors, however the polarity for those is
+ generally reversed from the batteries used by Altus Metrum
+ products. In particular, the Tenergy batteries supplied for use
+ in Featherweight flight computers are not compatible with Altus
+ Metrum flight computers or battery chargers. <emphasis>Check
+ polarity and voltage before connecting any battery not purchased
+ from Altus Metrum or Spark Fun.</emphasis>
+ </para>
<para>
By default, we use the unregulated output of the Li-Po battery directly
to fire ejection charges. This works marvelously with standard
<para>
You can monitor the operation of the radio link by watching the
lights on the devices. The red LED will flash each time a packet
- is tramsitted, while the green LED will light up on TeleDongle when
+ is transmitted, while the green LED will light up on TeleDongle when
it is waiting to receive a packet from the altimeter.
</para>
</section>
</listitem>
<listitem>
<para>
- RF interface for battery charging, configuration, and data recovery.
+ RF interface for configuration, and data recovery.
</para>
</listitem>
<listitem>