Allflex Panel Antenna Tuning Document July 04. Panel reader customer tuning doc july 03 new Rev.doc4 Page 1 of 11

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1 Getting Started. Allflex Panel Tuning Document July The antenna / reader kit is comprised of a control box (metal box with ammeter, buzzer, flasher lights etc), plus the antenna (black plastic panel). The control box is screwed to the antenna with 2 stainless steel screws and the 2 components (box and antenna) are joined by a cable that plugs into the control box. 2. A good starting point is to assemble the system and power it up in a free air environment (an area away from steel, computers, motors etc). Note. The system is designed to run off an automotive battery or a specific 240volt AC power supply. You should not be testing with anything other than these power sources. When testing originally in free air, have all other electrical equipment switched off totally and not connected to the antenna. 3. This free air reading will vary from model to model. It is usually around 0.4 amps for large antennas and around 1.20 amps for medium antennas. The read distance for cattle tags should be around mm and mm for sheep tags. 4. Move the antenna to where it is to be mounted in the race or crush. As you can see from the picture above, the antennas can be mounted directly onto steel pipe work if required; however, you should note that steel work does not form a frame around the perimeter of the antenna. Metal that forms a continuous frame around the antenna will definitely absorb all the transmitted power and you will be unable to tune out this effect. Similarly, the antenna cannot be mounted onto steel plate, because again, the steel plate will absorb all the energy and this cannot be tuned out. Note even as shown, the antenna should be mounted on plywood to protect it from the damage. Page 1 of 11

2 Allflex Panel Tuning Document July Note the ammeter reading when you have located the antenna in the new position. If the current has decreased, the antenna has been detuned by steel and needs retuning. If the ammeter has only moved marginally (say 0.1 for large and 0.3 for medium), or not at all, check the read distance, it is likely that the system does not require any tuning. In the example above, the steel certainly detunes the antenna but it can be retuned and will work very well. Tuning 6. If you decide that the antenna has been detuned and by positioning it in the race, or crush it will need tuning. To do this you will need to open the control box. Inside the control box you will see the electronic circuit board that drives the antenna at the end you can see 2 wires (the antenna wires) that join the circuit board. Below that you will see 2 banks of small green square components. (They are the tuning caps). Beside the tuning caps you will see rows of pins. Some of the pins will have small plastic shunts joining some of the pins. These shunts are used to join more tuning caps into the circuit. There are spare shunts taped inside the lid of the box. 7. Before you start, use the record sheets below to record the original factory shunt positions and current (when the antenna is in free air and mounted in the desired location). The small sketch below represents the 2 banks of pins as well as location of the shunts as showing the photograph. Page 2 of 11

3 Allflex Panel Tuning Document July Record the original factory shunt positions and current drawn in free air and then when located in the race or crush. Free Air Current when in position? 9. Now that we have a starting point we will alter the number of tuning caps in the circuit to try and tune out any effects of steel etc. Note - when tuning, keep the shunts balanced on each side / row. That is, if you move a shunt on the left row of pins, position a shunt in the same position on the right row as well. Tuning is done with the power on. What you want to see is the current peak. When you see the current peak the antenna is tuned. 10. Given that there are 5 sets of pins, that means that there are 31 different combinations where you can place pins. It is smart to follow a sequence when tuning so that you alter the tune incrementally rather than randomly. 11. To do this, start by removing all the pins. 12. Then step through each combination and record the current as you go. (Spare shunts are taped under the lid) However, we know if you want to take a short cut experience tells us that large size antennas usually tune between combinations 0 and 6 and mediums between combination 22 and 31. If you wish to save some time you can start around these values rather than trying every combination. 13. At the end of all combinations, review what combination gave you the peak current reset the shunts to that combination and test the read distance. The antenna should be tuned and provide good read distances. 14. Please use the images on the following pages to record the current for each combination. Page 3 of 11

4 Allflex Panel Tuning Document July 04 Combination 0 Combination 1 Combination 2 Combination 3 Combination 4 Combination 5 Page 4 of 11

5 Allflex Panel Tuning Document July 04 Combination 6 Combination 7 Combination 8 Combination 9 Combination 10 Combination 11 Page 5 of 11

6 Allflex Panel Tuning Document July 04 Combination 12 Combination 13 Combination 14 Combination 15 Combination 16 Combination 17 Page 6 of 11

7 Allflex Panel Tuning Document July 04 Combination 18 Combination 19 Combination 20 Combination 21 Combination 22 Combination 23 Page 7 of 11

8 Allflex Panel Tuning Document July 04 Combination 24 Combination 25 Combination 26 Combination 27 Combination 28 Combination 29 Page 8 of 11

9 Allflex Panel Tuning Document July 04 Combination 30 Combination What combination gave you the maximum current? What current was achieved? What was the best read distance was achieved? Page 9 of 11

10 Allflex Panel Tuning Document July 04 Reader PCB Assembly Ammeter with 1 Ampere fullscale range Red 6 Volt Battery Blk Figure 1(a) Panel Reader largest values To Exciter Amplifier Output Equivalent Circuit Figure 1(c) smallest values Figure 1(b) Page 10 of 11

11 Allflex Panel Tuning Document July 04 The following table represents the jumper positions and the incremental sequence in which jumpers should be added for tuning: Largest Capacitor Value 1500 pf 1000 pf 470 pf 220 pf Smallest Capacitor Value pf Current Value Measured Total Tuning Capacitance Combination Number Page 11 of 11