Telemetry Control Box Assembly GuideThe Telemetry Control Box (A3042) is a receiver that utilizes the Animal Location Tracker (A3038) baseboard in conjuction with a feedthrough and display board in order to allow the user to utilize external antennas. This maunual will describe how to construct a TCB from scratch.
Before we get the TCB ready for quality control, we must first prepare a baseboard. Each baseboard needs a modification of a 100pf capacitor from DC7 to ground. We use the via underneath DM1 to solder a capacitor to ground using a wire link. We also must load the DC-DC converter by bending back its legs and cutting them shorter.
The first stage of quality control involves tuning the detector modules. First, program each detector module along with the baseboard. Then, we measure their current consumption and input a sweep on each detector module allowing us to veiw the module's response with an oscilloscope. We then tune the detector module by changing the variable capacitor until the trace of test point "D" is linear with as steep of a slope as possible. We also assign it a hexidecimal code for identification.
Quality Control 1 measures two things: the frequency response of the detector module as well as the saturation point of its amplifiers. We measure frequency response by doing an SNA sweep utilizing a program called RF Explorer. We then save each sweep data as a CSV file and use a python script to plot the response of all of the detector modules on the same graph. To measure the saturation of the amplifiers we use the handheld signal generator and spectrum analyzer made by RF Explorer, increasing the power input by intervals of 20dB from -100dBm to -40dBm. We record the power output at each interval after the amplifiers.
This stage of QC tests the antenna mapping as well as the sensitivity of the detector modules. But first, we must assemble the TCB by placing each circuit inside of the TCB enclosure: the display board (A3042DP), the feedthrough board (A3042SF), and the baseboard (A3042BB). We must keep the lid off of the TCB in case something needs to be changed within. To test all of the detector modules, we input various power levels of a test transmitter into each antenna. We then record its ADC count. We also measure the point at which 90% of the signal is received. This process will help determine if one of the detector modules is behaving differently from the others. To get the power level on the antenna we must take a recording from the TCB and play the recording in the neuroplayer at the same time. We then open the tracker window and enable verbose which allows us to see which antenna is receiving power and how much of the signal it is receiving.
The final stage of quality control is a comparison to a TCB which has already passed all stages of QC. We begin by connecting four antennas to both TCBs (one of which we already know is up to standards) by using a T-BNC junction, splitting the same antenna signal in half. We then place four transmitters of two different types, one of each type in two identical plastic containers filled with water. We then use the neurorecorder to record ourselves moving within the faraday canopy with the transmitters turned on. If the new TCB sees reception on par with that of the good TCB then the new TCB has passed QC3.