Fast Fade - Berkeley Varitronics Systems Fox Manual

FAST FADE

Fast Fade saves blocks of 64 consecutive samples of dBm in PCMCIA card records. Also included in each block is the time,date
and GPS position of the measurement.
Each one of the 64 dBm samples is the average of 1,2,4,8 or 16 A to D measurements selected at the start of the measure-
ment.
The dBm value displayed on the FOX display is the average of the 64 samples saved on the PCMCIA card (also displayed is
PCMCIA storage and GPS status).
Note: FOX display and PCMCIA overhead is about 60 msec, so that when sample rates of 1,2 or 4 are selected, the number of
measurements per second is limited by this overhead time.
Fox Sample Conversion Times
# of A/D samples Time (msec)
selected per measurement
(includes overhead)
1 67
2 67
4 67
8 91
16 167
# of samples Storage Time (minutes)
selected 2 Meg PCMCIA card (saving GPS LAT and LON, 83 bytes saved per measurement)
1 28
2 28
4 28
8 38
16 70
One CHAN (ATA Save On, RF Dump Off) (Times include display and PCMCIA save overhead)
# A/D samples Time (msec)
selected per measurement
64 60
128 70
256 90
512 140
4096 800
# A/D samples Storage Time in minutes
selected 2 Meg PCMCIA card (saving GPS LAT and LON, 24 bytes of data saved per measurement)
64 85
128 104
256 132
512 208
4096 1456
This feature is only available for the following measurements:
20 CHAN, VAR SWEEP, 1 MHZ SWEEP
# 64 dBm measurements
saved per second
15*64=960
15*64=960
15*64=960
11*64=704
6*64=384
# measurements/sec saved
(a single 8 bit value/measurement)
17
14
11
7
1
Page 8