URL: http://www.ee.cornell.edu/~spp/rockets/SAL/sequence.html

Date:______________

NRL:

Note: All measurements assume the FTP is stowed in its channel.

1. Check Nominal Currents:
   

   Nominal	Recorded
   +18V  @ 120 mA	mA
   -18V  @  80 mA	mA
   +9V @ 16 mA	mA

2. Verify that the FTP MSB signal to TM is 300 mVpp signal  with 2.5 VDC offset.
   

   Nominal	Recorded
   300 mVpp	mVpp
   2.5    VDC	V

   
   

3. Check  signal on Langmuir Probe coax shield  (outside of SMB connector) with Cornell experiment on, but Cornell spheres grounded.
   

   Nominal	Recorded
   280   mVpp	mV
   1  V DC	V

   
   

4. Check  signal on Langmuir Probe coax shield with Cornell experiment on, but apply 1V to all spheres
   

   Nominal	Recorded
   280 mV AC	mV
   2       VDC	V

5. Disconnect SMB cable from NRL electronics to the probe.  In its place apply the 20 M Ohm resistor-alligator clip assembly.  Attach the alligator clip to ground. Check the FTM MSB (10 most significan bits) on the TM display.  (A quick and dirty check is to touch the payload (ground yourself) and then the sphere. The FTP MSB sinwave should saturate.)
   

   Nominal	Recorded
   1.23 Vpp	Vpp

   
   

6. • __ Exercise the boom deployment microswitch
   • __ Check thermistor.

---

UNH:

1. Before sequence test:

   • Check nominal current for one of the conditions shown below:

     Nominal	Recorded
     +28 @ 165 mA (spheres grounded)	mA
     +28 @ 320 mA (1 VDC to all spheres)	mA
     +28 @ 390 mA (spheres floating)	mA

     
     

   • Verify Cornell Floating pot'l signal appears on UNH HK (Kelley Gnd Monitor).

   • With NASA interface attached (power, major and minor frame on, and
     apogee LOW (= 0V)), Cornell spheres grounded, check outputs to NASA:

     pin#	name	Voltage	Recorded
     22	Kelley Gnd Monitor	0	V
     9	Grid3 Voltage	0	V
     23	Grid2 Voltage	2.5	V
     10	Anode Voltage	2.5	V
     18	Current mon	3.1	V
     21	Ch5 (veto)	2.5	V
     20	UNH Chan1	0-1V noise	V
     8	UNH Chan2	0-0.5V noise	V
     19	UNH Chan3	0-0.2V noise	V
     7	UNH Chan4	0-0.1V noise	V

     
     

   • Now connect the Cornell interface and apply +1 VDC to all of the
     Cornell spheres to send a voltage of 1 VDC to UNH. (difference:
     KG(pin 2) - CI(pin 1) >= 0). I'll call KGND = KG-CI. Pins that
     should have changed:

     pin#	name	Voltage	Voltage  w/ KGND level 1 Vpp	Recorded
     22	Kelley Gnd Mon	(KGND)/2	0.5V	V
     23	Grid 2 Voltage (-9V Bat monitor)	(5 - KGND)/2	2.0V	V
     10	Anode Voltage (+9V Bat monitor)	(5 + KGND)/2	3.0V	V
     21	Ch5 (veto)	(1.5+KGND+9)/4	3.0V	V

   • Next, check pin 21 (Ch5 Veto) with the apogee signal set HIGH (+5V). There should be 4 consecutive voltages:
     

     Voltage Rule	UNH Ch5 w/ KGND=1.0V	Recorded
     (1.5 + KNGD + 9)/4	3.0 V	V
     (3.0 + KGND + 9)/4	3.3 V	V
     (5.0 + KGND + 9)/4	3.8 V	V
     (8.0 + KGND + 9)/4	4.5 V	V

   • During sequence test
     

     • Verify the UNH Chan 5 signal changes operation modes at apogee. (Apogee signal goes from 0 V to +5V at apogee).
     • Check Kelley ground monitor HK line.
       • Apply signal to the Cornell spheres to generate +1 V and then +2 V floating potential signal. Cornell interface voltages should be GND (pin 1) (pin 2, sphere average).

---

Cornell:

1. Before sequence test
   

   • Check Nominal Currents: (+18 @ 85 mA, -18 @ 94 mA)
   • Apply sinusoidal signals to each sphere and verify a response is seen by TM on the groundstation for all channels.
   • Verify Cornell Floating Pot'l signal is seen by UNH and NRL (This requirement already mentioned in the UNH and NRL requirements)
     

2. During sequence tests:

   Input Signal	Sphere	Nominal Output	Verify
   200 Hz, 45 mVpp	3	HF23 = 4.0 Vpp HF34 = 4.0 Vpp V34H = 2.3 Vpp	_____ _____ _____
   	1	HF14 = 4.0 Vpp HF21 = 4.0 Vpp V21H = 2.3 Vpp	_____ _____ _____
   200 Hz, 800 mVpp		V1s = 750 mVpp	_____
   	4	V43M = 4 .0 Vpp V14M = 4.0 Vpp	_____ _____
   	2	V12M = 4.0 Vpp	_____
   1 V DC	1,2,3,4	CU float pot'l (aka FlowPot) = 3.43 V	_____

   Note: TM version of CU floating potential has a 2.43 V DC offset.

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