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About Mr.RC-Cam

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    RC-Cam Mentor

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    R/C, FPV, Embedded Programming, Electronic Design.

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  1. Thank you for the kind words. Your technical assistance was extremely helpful in identifying the LCD Keyboard problem, so it was a joint effort.
  2. I suppose that is the best we can do for now. Given the random nature of the Chinese boards I expect the LCD-Keyboard shield compatibility issue will pop up again. To be proactive about this I have released a new version of the firmware (V2.3). It is posted here: https://www.rc-cam.com/forum/index.php?/topic/4139-diy-rf-power-vswr-meter-low-cost/&do=findComment&comment=29002 There's now a keyboard debug function. It will display the key-press code value when each menu button is pressed. The feature is enabled via the config.h file using DEBUG_KYBD found under the Troubleshooting section. What does it do? For those that need help solving keyboard compatibility problems: Enable DEBUG_KYBD in config.h, re-flash the firmware and then report the five keypress code values shown on the LCD. When posting for help be sure to include the two A0 voltage values mentioned earlier. Also, the config.h file now supports an alternate LCD/Keyboard shield. Currently there's two choices, my DFRobot branded board (LCD_SHIELD_DFR) and the clone used by HF_ATL (LCD_SHIELD_ALT1). The shield choice is made by enabling LCD_SHIELD_DFR or LCD_SHIELD_ALT1 found under the LCD/Keyboard Shield Type section.
  3. You are welcome. Thanks for letting me know the keypad is working now. I should add a note to the docs about the changes for your LCD/Keypad shield. Is there a Chinese manufacturer's name or unique ID printed on your DFRobot clone shield so it can be identified by other project builders? That's a sane/reasonable value with nothing connected to the SMA. It should be fine for VSWR only measurements. But a calibration will be required for accurate RF power measurements .
  4. The 2K ohm (1.99K) resistor is a good A0 choice for your LCD shield. Now the various key press codes will need to be re-mapped. In the RF_Power_Meter.ino file, go to the ReadLCD_Buttons function (starts at line 435). Replace the adc_key_in code section (from lines 486 to 506) with this revised snippet: if (adc_key_in > 1000) { kybd = btnNONE; } else if (adc_key_in < 50) { kybd = btnRIGHT; } else if (adc_key_in < 265) { kybd = btnUP; } else if (adc_key_in < 525) { kybd = btnDOWN; } else if (adc_key_in < 690) { kybd = btnLEFT; } else if (adc_key_in < 865) { kybd = btnSELECT; } else { kybd = btnNONE; } Upload code then check all the button functions. Hopefully you are rewarded with button press happiness. EDIT: Beginning with firmware V2.3 this alternate key press code can be selected in the config.h file. Choose LCD_SHIELD_ALT1 to enable it.
  5. The voltages and key press values are now a bit too low. Increase the resistor value a small amount (try ~1.8K). Ideally the A0 voltage with no button pressed will be 2.45V - 2.50V with a "None" key press value between 1015 and 1023. With the Select button pressed you should see about 2.0V. Get as close to these voltages as practical then report all the key press debug values. Important: Never power the meter without the A0 resistor installed.
  6. Almost there. Try a 1.5K and report the debug values. With the 1.5K installed, please measure the A0 voltage when no buttons are pressed and also when the select button is pressed.
  7. Those values show we are on the right path. But the key press values are still a bit high. Replace the 2.7K ohm with a 2.2K and report all the key press debug values again.
  8. Thanks for checking the 3.3K resistor. Mine measures 1.82K ohms between A0 and GND (with 3.3K installed). So that means your LCD Keyboard Shield has different keypad summing resistors on it. The workaround will require changing your 3.3K A0 resistor value. Begin with a 2.7K ohms instead of the 3.3K. Then report back the button values using your "Serial.println(adc_key_in);" debugging code. This will allow me to confirm we're on the right path.
  9. Before we do any tinkering please verify A0's 3.3K ohm resistor value again. Your photo's colors might be deceiving me, but it appears that the A0 resistor's color code is ORG/ORG/BLK/VIO/VIO. That would be an incorrect value (3.3G ohms).
  10. All of your button values are too high. Confirm that you have installed the correct resistor value (3.3K) on pin A0 (see image below). BTW, does the artwork of your LCD Keypad board match the image below? If it is different in any way then the A0 resistor value may need to be altered.
  11. If JoostB's advice does not get you going then we'll need to know a few things. For example: 1. What exactly are you using to power the meter? 2. What is the measured voltage on the Arduino's VIN pin? This is the pin that supplies power to the AD8313 board. 3. Do the five keypad buttons work correctly? Keep in mind that the meter will give you that warning if you try to use it while powered by the USB port. That is to say, an external power source must be connected to the DC Input (barrel plug jack) on the Arduino board. I recommend using 12VDC (3S LiPO battery).
  12. I don't have any experience with that module. But since most of the Chinese diversity clone modules use similar circuitry I suspect it might work. FWIW, I'm not a fan of it's SMA orientation; Their location will require antennas with Right Angle SMA's and I do my best to avoid them because of their RF losses.
  13. I agree, they made it very convenient. I can't help you with that since I do my own printing. But if you use a print service then please report how you liked it. BTW, some community libraries have 3D printers and experts are on-hand to help get you going.
  14. 2011 FPV Product Predictions

    It's Jan 2018, time to reflect. It is amazing how dramatic the FPV market has changed since this thread was posted seven years ago (2011). We now have an endless number of FPV product choices, with more features than most will ever use, and all at bargain prices. It makes me wonder what FPV gadgets we will get to play with in another seven years (2025). But I'll take a gamble and predict this 2025 flying model: A 25mm sized drone with ultra HD video and 2-hr flight times. All for under $200 USD. Besides being popular for indoor FPV, it will also be commercialized for consumer home automation & home security.
  15. Oh my. A simple shared video "Tee" connection will create what is called a double-terminated video signal. This often works because a monitor's AGC will band-aid the problem. But this is lipstick on a pig. Doing it will downgrade the video quality and increase the likelihood of video stability problems during weak FPV signal events. All of this is why you need a separate buffered video signal if you want to attach another video device to a vRx. My Thoughts? If you want the best possible video then do it right. Use a dedicated/buffered video output to the DVR.