Calibration

Booster should be pre-calibrated by the supplier, users should never need to recalibrate. Incorrect calibration can damage Booster and any devices connected to it.

• Calibration is performed using the VCP interface
• To calibrate use a 50 Ohm terminator that can safely dissipate 5 W
• <channel number> is 0...7

Note: Partial command outputs are saved only in volatile memory, rebooting device will clear any calibration step (e.g interlock calibration steps 1/2. When both commands are executed, final result is saved in EEPROM)

Module Power Amplifier Current Calibration

Each RF Channel has a power FET that requires a 50mA bias current. The bias current is controlled by a DAC that biasses FET gate voltage. The calibration can done with the inputs and outputs terminated or open. To calibrate the DAC voltage required to achieve 50mA bias current run the biascal <channel number> <desired current> (50 mA) command.

Example output from bias current calibration:

> biascal 1 50
[*] 017% [#         ] 9/51
[..] trimmed
[*] 078% [#######   ] 40/51
[*] 092% [######### ] 47/51
[*] 098% [######### ] 50/51
[*] 100% [##########] 50/50
[biascal] done, value = 1677, current = 50

Output Forward Power Interlock and Diagnostics Calibration

Connect the amplifier input to a 200MHz source, connect calibrated power meter to its output.

1. Adjust the input power until the output power is approximately 23 dBm
2. Run intcal <channel number> 1 <p_out> where <p_out> it the actual output power (e.g. intcal 0 1 23.2 for 23.2 dBm output power when calibrating channel 0)
3. Adjust the input power until the output power reaches approximately 33dB
4. Run intcal <channel number> 2 <p_out>

Output from first step of input calibration:

> intcal 4 1 23.0
[intcal] Calibrating output interlock ch 4
[ointcal] trying value 4095, status 0
[ointcal] trying value 3995, status 0
[...] trimmed
[ointcal] trying value 2274, status 0
[ointcal] trying value 2273, status 1
[ointcal] done, interlock value = 2273
[intcal] Calibration step = 1 completed = 2273
[intcal] done, got 1-point cal val 2273 pwr 23

Second step

> intcal 4 2 35.0
[intcal] Calibrating output interlock ch 4
[ointcal] trying value 4095, status 0
[ointcal] trying value 3995, status 0
[...] trimmed
[ointcal] trying value 3108, status 0
[ointcal] trying value 3107, status 1
[ointcal] done, interlock value = 3107
[intcal] Calibration step = 1 completed = 3107
[intcal] done, got 2-point cal val 3107 pwr 35
[intcal] done, got power factors a=69.58 b=671.58

A successful execution of 2 (upper) commands will result in calculated interlock factors. At this point results are saved to EEPROM.

[intcal] Calibration step = 1 completed = 3107
[intcal] done, got 2-point cal val 3107 pwr 35
[intcal] done, got power factors a=69.58 b=671.58

Output Reverse Power Interlock and Diagnostics Calibration

Connect the amplifier input to a 200MHz source, terminate its output or leave open (unconnected) as instructed.

1. With the output terminated, adjust the input power until the output power is approximately 0dBm
2. Run calpwr <channel number> 1 <p_out>
3. Keeping the input the same, remove the terminator to give an open-circuit load
4. Run calpwr <channel number> 3 <p_out>
5. With the output terminated, adjust the input power until the output power is approximately 33dBm
6. Run calpwr <channel number> 2 <p_out>
7. Keeping the input the same, remove the terminator to give an open-circuit load
8. Run calpwr <channel number> 4 <p_out>

Example outputs:

• 1st step

> calpwr 4 1 0.0
[calpwr] done, value1 for pwr 0 = 590

• 2nd step - At this point results are saved to EEPROM.

> calpwr 4 2 35.0
[calpwr] done, value2 for pwr 35 = 3009
[calpwr] done, a=69 b=590

Input power detector calibration

Connect the amplifier input to a 200MHz source, terminate its output. Termination is optional, since device won't connect RF switch during input power measurement.

1. Adjust the input power to -20 dBm.
2. Run inpcal <channel number> 1 <p_out>, where p_out is -20
3. Adjust the input power to -5 dBm
4. Run inpcal <channel number> 2 <p_out>, where p_out is -5

Example output: 1st step:

> inpcal 4 1 -20
[input_cal] done, got 1-point cal val 407 pwr -20

2nd step, results are now saved to EEPROM.

> inpcal 4 2 -5
[input_cal] done, got 2-point cal val 1226 pwr -5
[input_cal] done, got power factors a=0.02 b=-27.45