[time-nuts] Performance of the Thunderbolt self-survey / antennas

[WB6BNQ]

Mark,

Is that thin or deep pan ?

Bill....WB6BNQ


Mark Sims wrote:

> Now that I have a precise spot (+/- 4cm) known on my front deck I set up a tripod and did numerous 1400 point self-surveys with a Thunderbolt.  This spot is surrounded by very tall trees and multipath from the trees,  steel gates and stucco walls,  a house,  an iron fence, etc.  I used four different antennas:
>
> 1) A Sokkia geodetic grade L1/L2 antenna
> 2) A Aero survey grade L1 only antenna
> 3) A Datum timing antenna
> 4) A cheap patch antenna
>
> I could not find any repeatable differences in the performance of any of the antennas.  The $3000+ geodetic grade antenna performed no better than the cheap $5 dollar patch antenna.
>
> Composite performance over 22 runs was:
> Avg lat error: 1.4 feet,  std dev 4.48 feet
> Avg lon error: 2.24 feet,  std dev 2.87 feet
> Avg alt error: 6.00 feet,  std dev 15 feet
>
> Although I did not do any extended timing tests between the antennas,  the numbers that I did see make me suspect that timing performance among the antennas would be similar.  A couple of 24 hour runs between the cheap patch and the geodetic antenna were the same.  A cheapskate could probably get excellent results by mounting a cheap patch antenna in the middle of a large pizza pan ground plane.
>
> _________________________________________________________________
> Windows Live™: Keep your life in sync.
> http://windowslive.com/explore?ocid=TXT_TAGLM_WL_BR_life_in_synch_062009
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.