[aprssig] Pocket Tracker???

[Stephen H. Smith]

bruninga at usna.edu wrote:

>Scott says:
>  
>
>>This might interest you [for an APRS TX kit]
>>http://www.sarl.org.za/forum/topic.asp?TOPIC_ID=249 
>>    
>>
>
>Please tell him to keep it at 12 watts and don't
>cut it back to 5W!
>
>The duty cycle of an APRS transmitter even at
>30 second rate is less than 3%.  Thus the
>12 watt device (probably takes 25W DC
>input power) but at 3% dutycycle this is only
>an average device dissipation of 750 mW
>and can easily be dissipated by just the
>PCB.
>
>  
>

This translates into a continuous drain of 83mA from a 9V battery!  
Obviously not practical.

 Looks like a high-power PT would have to be in a substantially larger 
box in order to accomodate a much larger battery.    But then, at least, 
one could easily add the 60mA drain of a GPS-18 or similar.   



Stephen H. Smith    wa8lmf (at) aol.com
EchoLink Node:      14400    [Think bottom of the 2M band]
Home Page:          http://wa8lmf.com

"APRS 101"  Explanation of APRS Path Selection & Digipeating
  http://webs.lanset.com/wa8lmf/DigiPaths

Updated APRS Symbol Chart
  http://webs.lanset.com/wa8lmf/miscinfo/APRS_Symbol_Chart.pdf   

New/Updated "Rev G" APRS     http://webs.lanset.com/wa8lmf/aprs
Symbols Set for UI-View,
UIpoint and APRSplus:


-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.tapr.org/pipermail/aprssig/attachments/20051119/dee1faa7/attachment.htm