SOP BCC Transceiver Tuning - In-Season Tune Up

From PTAGISWiki

	Standard Operating Procedure
Subject:	SOP BCC Transceiver Tuning - In-Season Tune Up
Author:	Scott and Alan
Approved by:Scott L	APPROVED

Contents 1 Objective 2 Scope 3 Responsibilities 4 BCC GMC Calibration Procedure 4.1 Step 1 - Check Read Range 4.1.1 Decision 4.2 Step 2 - Check Water Level 4.2.1 Decision 4.3 Step 3 - Adjust the Drive Circuit 4.3.1 Tools Required 4.3.2 Setup 4.3.3 Course Tune Variable Capacitors 4.3.4 Optimize Drive Signal 4.3.5 Decision 4.4 Step 4 4.4.1 Adjust the Receiver 4.4.2 Decision 5 References

Objective

This procedure defines in-season calibration of the transceiver deployed at BCC - Bonneville PH2 Corner Collector. This is intended to be performed during GMCs. The procedure for complete calibration of a newly installed transceiver can be found here: http://php.ptagis.org/wiki/index.php/SOP_BCC_Transceiver_Tuning.

Scope

This procedure is to be used as necessary to verify and/or restore system performance of the BCC transceiver itself. This procedure is intended to provide optimization of transceiver performance during a routine GMC.

Responsibilities

This procedure is to be performed by qualified PTAGIS staff.

BCC GMC Calibration Procedure

Gauging the performance of the BCC transceiver is based on read-range. This is measured manually with an SST test stick, referenced to the baseline mark on the downstream grating near the antenna. The measurements are made in inches, with positive measurements denoting longer read-range from the antenna (good) and negative measurements denoting shorter read-range to the antenna (bad).

Figure 1 - SST Test Stick on Downstream Grating

Step 1 - Check Read Range

When arriving on site to check the performance of the transceiver, measure the read range.

• Note: Remove any noise generating devices from yourself that may interfere with the test. These could include other test sticks, car keys, credit cards and electronic security cards.
• Enable the outdoor tag detect buzzer.
• Start with the test stick at the +20" mark and slowly (~1" per second) move the test stick into the field until it reads.

Decision

If the stick is detected at a positive measurement or at 0", performance is adequate. Stop at this point and document the activities in the pitevent for the GMC.
If the stick is read at a negative measurement, or not read at all, proceed to step 2.

Step 2 - Check Water Level

If a negative read-range is measured, check the water level using using the Red Lion HMI in the PIT tag room.

• Press the "Menu" button on the HMI and/or press the "M" button on the touch screen to view live water level data.
  • LT_01 is the south water level sensor
  • LT_02 is the north water level sensor

Decision

We do not calibrate the BCC transceiver if the water level is outside the 10.8' to 12.2' window. If the water level is lower than 10.8' or higher than 12.2', stop at this point and document the activities in the pitevent for the GMC.

If the water is between 10.8' and 12.2' and the stick is read at a negative measurement (or not read at all) continue to step 3.

Step 3 - Adjust the Drive Circuit

Tools Required

The following tools or equivalents will be required to perform this procedure and are stocked in the BCC PIT tag room:

• Gw Instek GOS-6103C oscilloscope (or Fluke 192C Scopemeter or equivalent)
• Potentiometer adjusting tool (Tweaker)
• Tektronix Current Probe P6021 or equivalent
• BNC Cable
• TX1400SST test stick
• Audible Tag Detect Buzzer

Setup

• Remove the protective plexi-glass cover in the transceiver to expose the antenna drive leads.

WARNING - HIGH VOLTAGE - To access the antenna current, the Plexiglas cover must be removed. Use caution to avoid shock hazard during this procedure.

• Attach the current probe to channel 1 (or A) of the scope and to the white wire coming out of the Filter and Detector.
• Attach one end of the BNC to BNC cable to channel 2 (or B) of the scope and the other end to the FBB out BNC on the side of the BCC transceiver.

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 1 and turn ON the high frequency noise reject filter, this will allow viewing the signal at “FBB OUT” easier.

Course Tune Variable Capacitors

Note: the "1" on the coarse capatior switches means the capacitor is in the circuit. The "0" means it's out of the circuit.

1. Monitor the antenna current and FBB signal on the oscilloscope.
2. Select the coarse capacitors via the switches on the tuner board until the "TUNED" LED on the Diagnostics Module is lit. Goal: select capacitors such that the variable capacitor is centered in it's adjustable range.

Figure 3 - Tuning Capacitors

Figure 4 - Diagnostics Board

Optimize Drive Signal

1. Slowly adjust variable capacitor C3 (tweak and wait 2 seconds for the auto-tune routine) until the reader tunes the antenna to the maximum possible current (monitor channel 1 of the scope). The black dot on C3 should be in the lower left quadrant when finished. Reference Figure 5 - Auto-tuner Board for the location of C3.
2. Continue to adjust capacitor C3 until the moving plates of the Antenna Tuning Variable Capacitor slightly move inward and the current amplitude just starts to decline. Monitor channel 2 (FBB Signal) of the scope, you should see the noise level is reduced. This is a slight adjustment. The peak to peak FBB signal should be less than 100mV, not counting spikes.
3. Repeat until optimized

Figure 5 - Auto-tuner Board

Measure the read-range with the test stick on the grating.

Decision

If the stick is detected at a positive measurement or at 0", performance is adequate. Stop at this point and document the activities in the pitevent for the GMC.
If the stick is still read at a negative measurement, or not read at all, proceed to step 4.

Step 4

Adjust the Receiver

Adjustment descriptions:
Receiver PCB Adjustments

• R42: 2 and 4 Khz Amplitude Adjustment.
• R38: 3rd Stage Amplifier Gain Adjustment.
• R27: High Frequency Filter Cutoff Adjustment.
• R34: Phase Shift Offset Adjustment.
• R17: 1st Stage Amplifier "Q" Adjustment.

Filter/Detector Adjustment

• C20: Vari-Cap, for detector tuning.

To adjust the receiver:

1. Place a tag in the field (near the large white antenna leads under the transceiver) to where it just starts to read.
2. Adjust potentiometer R42 so that the amplitudes of the 2kHz and 4kHz components of the signal on channel 2 (wide and narrow waves) are as equal as possible. For this adjustment set the scope time base to 0.5mSec/Div. The reading efficiency should improve.
3. Move the tag out of the field to where it barely reads and adjust potentiometer R42 to improve reading efficiency. Repeat this until reading efficiency can not be improved.
4. Adjust potentiometer R38 so the signal on channel 2 is minimized while maintaining good reading efficiency.
5. Adjust potentiometer R27 (High Pass Filter adjustment) fully CW so that the signal on channel 2 is minimized. Begin rotating R27 counter clockwise (CCW) until the reading efficiency is peaked (should be approx. between 1/3 and 1/2 of the way).
6. Adjust Filter and Detector capacitor C20 to improve reading efficiency. This should be a very slight adjustment.
7. Repeat steps 7 through 9 until reading efficiency is peaked.

Measure the read-range with the test stick on the grating.

Decision

If the stick is detected at a positive measurement or at 0", performance is adequate. Stop at this point and document the activities in the pitevent for the GMC.

In case of the stick still reading at a negative measurement, or not reading at all, there may be outside interference hindering transceiver performance.

• Verify on the "BCC Transceiver Status Summary" page (ftp://ftp.ptagis.org/Reports/bcc_transceivers/bcc.html) that recent transceiver performance does not indicate any issues.
  • Check "Hits per Tag" and "Active/Quiet Time" for recent anomalies.
• Check "Bad Tag Masks at BCC since 2007" (http://www.ptoccentral.org/cgi-bin/bad_bcc.cgi)
  • Verify that the number of PIT Tags detected on the previous day is appropriate for the current time of the season.
  • Verify that the number of bad tag masks is not out of the ordinary.
• Verify that the transceiver/antenna system has not suffered a catastrophic event. Begin troubleshooting if necessary.

If checking these reports shows no anomalous behavior, document the activities and results in the pitevent for the GMC. PTAGIS Field Operations will continue to monitor the system remotely and come to a consensus on future actions.



Figure 6 - Receiver Board


Figure 7 - Oscilloscope showing FBB signal

References

Digital Angel B2CC Operations and Maintenance Manual