PCsat telemetry equation
The following data were the consecutive telemetry blocks from PCsat
that I received yesterday, Oct 24, [1200bps 144.390MHz(B-side) AFSK].
And I calculated these telemetry in order of the cycle count.
[03:11:17 UTC] T#997,060,034,048,089,212,00111111,0000,1
[03:12:07 UTC] T#998,066,064,059,061,212,00111111,0001,1
[03:12:57 UTC] T#999,062,057,071,089,212,00111111,0010,1
[03:13:47 UTC] T#000,164,169,086,215,212,00111111,0011,1
Current -X : 0*60^3+0.0034*60^2+0.2284*60-26.6= -0.656 [mA]
Current -Z : 0*34^3+0.0096*34^2+0.864*34-53.8= -13.326 [mA]
Current -Y : 0*48^3+0.0023*48^2+0.473*48-23.2= 4.803 [mA]
Current +X : 0*89^3+0.003*89^2+0.4*89-26.6= 32.763 [mA]
Temp -Y : 0*66^3+0*66^2+0.3414*66-19.71= 2.822 [C]
Temp Batt B : 0*64^3+0*64^2+0.3414*64-19.71= 2.139 [C]
Temp XMIT B : 0*59^3+0*59^2+0.3414*59-19.71= 0.432 [C]
Temp -Z : 0*61^3+0*61^2+0.3414*61-19.71= 1.115 [C]
Temp -X : 0*62^3+0*62^2+0.3414*62-19.71= 1.456 [C]
Temp Stack B : 0*57^3+0*57^2+0.3414*57-19.71= -0.250 [C]
Current +Y : 0*71^3+0.0038*71^2+0.0084*71-19.8= -0.047 [mA]
Current Batt B : -0.00004*89^3+0.0158*89^2-3.32*89+259= 60.473 [mA]
B-Batt A Volt : 0*164^3+0*164^2+0.09774*164+0= 16.029 [V]
B-Batt B Volt : 0*169^3+0*169^2+0.09457*169+0= 15.982 [V]
Power out B : 0*86^3+0*86^2+0.0223*86+0= 1.917 [V]
8V Reg B : 0*215^3+0*215^2+0.0351*215+0= 7.546 [V]
Refer to the URL below for the more information.
http://www.ew.usna.edu/~bruninga/pcsat.html
--------------------------
PCSAT Telemetry Analysis
--------------------------
Side : A B
Freq. : 145.825 144.390
------------------------------------
1200bps : PCSAT-1 PCSAT-11 (AFSK)
(W3ADO-1)
9600bps : PCSAT-2 PCSAT-12 (FSK)
(W3ADO-2)
Example,
W3ADO-1>BEACON:SGATE:T#002,132,138,159,131,213,11111111,0001,0
^^
The "01" indicates that this is telemetry cycle 01.
The four values that correspond to the telemetry values are those
located directly after the telemetry count (which is represented
by T#XXX). On the telemetry packet above, the four telemetry
values are 132,138,159,131. The fifth value is a constant, which
represents the 5V reference. The table below identifies the
location of each value.
----------------------------------------------------------------------
Side Cycle FirstValue SecondValue ThirdValue FourthValue
Count
A 00 Current +X Current +Z Current +Y Current -X
A 01 Temp +Y Temp Batt A Temp XMIT A Temp +Z
A 10 Temp +X Temp Stack A Current -Y Current Batt A
A 11 A-Batt A Volt A- Batt B Volt Power out A 8V Reg A
B 00 Current -X Current -Z Current -Y Current +X
B 01 Temp -Y Temp Batt B Temp XMIT B Temp -Z
B 10 Temp -X Temp Stack B Current +Y Current Batt B
B 11 B-Batt A Volt B-Batt B Volt Power out B 8V Reg B
----------------------------------------------------------------------
The following table gives the unit conversion equations for each
of the telemetry values as to the coefficients of a general CUBIC
equation of the form Ax^3 + Bx^2 + Cx + D where X is the raw value
in the packet.
----------------------------------------------------------------------
Side Cycle Channel
Count A B C D
A 00 Current +X 0 0.0012 0.646 -25.96
A 00 Current +Z 0 0.0048 0.75 -54.6
A 00 Current +Y 0 0.0031 0.241 -25.3
A 00 Current -X 0 0.0024 0.414 -25.3
A 01 Temp +Y 0 0 0.3414 -19.71
A 01 Temp Batt A 0 0 0.3414 -19.71
A 01 Temp XMIT A 0 0 0.3414 -19.71
A 01 Temp +Z 0 0 0.3414 -19.71
A 10 Temp +X 0 0 0.3414 -19.71
A 10 Temp Stack A 0 0 0.3414 -19.71
A 10 Current -Y 0 0.0037 0.0264 -18.5
A 10 Current Batt A -0.00004 0.0114 -2.56 252
A 11 A-Batt A Volt 0 0 0.0984 0
A 11 A-Batt B Volt 0 0 0.09826 0
A 11 Power out A 0 0 0.0311 0
A 11 8V Reg A 0 0 0.0356 0
B 00 Current -X 0 0.0034 0.2284 -26.6
B 00 Current -Z 0 0.0096 0.864 -53.8
B 00 Current -Y 0 0.0023 0.473 -23.2
B 00 Current +X 0 0.003 0.4 -26.6
B 01 Temp -Y 0 0 0.3414 -19.71
B 01 Temp Batt B 0 0 0.3414 -19.71
B 01 Temp XMIT B 0 0 0.3414 -19.71
B 01 Temp -Z 0 0 0.3414 -19.71
B 10 Temp -X 0 0 0.3414 -19.71
B 10 Temp Stack B 0 0 0.3414 -19.71
B 10 Current +Y 0 0.0038 0.0084 -19.8
B 10 Current Batt B -0.00004 0.0158 -3.32 259
B 11 B-Batt A Volt 0 0 0.09774 0
B 11 B-Batt B Volt 0 0 0.09457 0
B 11 Power out B 0 0 0.0223 0
B 11 8V Reg B 0 0 0.0351 0
----------------------------------------------------------------------
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