SOP FS1001AB Tuning

From PTAGISWiki

	Standard Operating Procedure
Subject:	SOP FS1001AB Tuning
Author:	Darren Chase
Approved by:	Don Warf

Contents 1 Objective 2 Scope 3 Responsibilities 4 Tools Required 5 Procedure 6 References

Objective

The following procedure will be used to tune an FS1001A-B detection system.

Scope

This procedure is specifically used to maximize the FS1001A-B system stability and PIT-tag detection capability.

Responsibilities

This procedure is meant only for Digital Angel certified service technicians.

Tools Required

The following tools will be required to perform this procedure.

• Fluke 196C Scopemeter or equivalent
• Tektronix P6021 Current probe or equivalent ( Probe should be capable of 10Amps or higher)
• Agilent 10436B 10:1 scope probe or equivalent
• Potentiometer adjustment tool or small flat blade screwdriver

Procedure

1. Attach the Agilent probe to channel “A” of the scopemeter and the current probe to channel “B”. Attach the current probe to the brown wire (the orange wire can also be used if the brown wire cannot be easily accessed). Remove the shield that is covering the Receiver section of the Analog board and attach the Agilent probe to TP21 “COMP_IN” (this is the input to the comparator circuit).

   NOTE: Adjust the scope so that both signals can be displayed and measured at the same time. Both channels need to be AC coupled and set to measure the signal peak to peak. Set trigger on channel “B” and turn ON the high frequency noise reject filter, this will allow viewing the signal on TP21 easier.

2. Adjust exciter voltage all the way down by turning potentiometer RP2 “+VE ADJ” on Mother board clockwise (CW). (Silkscreen marking on the board is opposite, so disregard it).
3. Preset capacitor C29 in Receiver section of the Analog board to mid-range.(Transceiver power must be “OFF” when you do this! - Lift the colored plastic cover to see the plates of the capacitor; the moving plates should cover the half of the static plates).
4. Potentiometers R30 “HP FILTER” and R59 “COMP SENS” in Receiver section of the Analog board are pre-set at the factory and do not require any adjustment. These may be adjusted after the initial tuning is completed to maximize the tag detection.
5. Power the transceiver “ON” and hit “ENTER” on the front panel to get to the “Signal” display. By using the tuning jumpers located next to the yellow NPO capacitors, maximize the antenna current displayed on the channel “B” of the scope. Adjust the variable tuning capacitor C100 to fine-tune the antenna.

   NOTE: When using the tuning jumpers monitor the phase “Ph” on the transceiver’s “Signal” display, if the phase is higher than 50% - remove capacitance and if the number is lower - add capacitance (The phase will not go below 0, this means that there is no swing through 0 like it is in standard FS1001A reader). When the system is tuned the phase should be around 50±5%.
   

6. Adjust exciter voltage by turning potentiometer RP2 “+VE ADJ” on Mother board counter clockwise (CCW) to set desired antenna current (Channel “B” of the scope, should not exceed 8Amps peak to peak).
7. Press “MENU” button on the front panel to navigate to the “Diagnostics” menu, hit “ENTER” then navigate to the “Test Tag” settings and select the test tag “ON” and hit “ENTER”. Press “ESCAPE” to go back to the main display and view the test tag “Hit Rate”. Adjust potentiometer R96 “VTT LVL” clockwise (CW) so that the hit rate is somewhere between 30 and 40 on the display.
8. Adjust variable capacitor C29 while monitoring the signal from TP21 on channel “A” of the scope so that the amplitudes of the 2kHz and 4kHz signals are as equal as possible.
9. Check the hit rate to see if there are any improvements made to the count, if so adjust the voltage potentiometer R96 CW to achieve a 20-30 hit rate.
10. Adjust C100 in order to increase the hit rate.(Reference picture for location).
    

    
    

    NOTE: Allow few seconds for the hit rate to update when making adjustments. Also, buzzer sound can be used to track changes in reading efficiency, although it might reduce the hit rate.
    

11. Repeat steps 8 through 10 while adjusting potentiometer R96 CW until you are unable to get a hit rate.
    
12. Adjust the hit rate to around 20-30 and adjust potentiometer R30 (This is the High Pass Filter adjustment) fully CW so that the signal on TP21 is minimized. Begin rotating R30 counter clockwise (CCW) until the hit rate is peaked (Should be approx. between 1/3 and 1/2 of the way).
13. Adjust potentiometer R59 (This is the comparator sensitivity adjustment) in order to increase the hit rate. If there are no improvements – set it to mid-range.
14. Check if the antenna current measurement on the channel “B” of the scope and the transceiver “Signal” display match. If not - adjust the current gain “Curr gain %”. This is located under the “Diagnostics” menu and is set at 100% as a default. If the transceiver’s display value is lower - increase the number until both the display and the measured signals agree (Should be at 140±20%).

    NOTE: Adjust channel “B” so the best resolution of the signal is achieved (Stretch the signal across the entire display).

Notes

1. When the system is tuned the signal at TP21 with no tag in the field should be around 60 to 100mV peak to peak and the phase “Ph” should be around 50±5%.
2. If after tuning the transceiver there is still the presence of noise or instability it may be necessary to connect the digital ground to the analog ground via the jumper pads JP1.1 “R12V” and JP1.2 “RVCC” that are located in the upper right hand corner of the Analog board. This can be tested by using the blade of a screwdriver but it may be necessary to scratch the surface free of the conformal coat that is on the board (Slight antenna tuning might be needed after the grounds are connected).

References