Errors and learning with Bitx40. - Some notes.
LU1DLA, Alejandro Linconao
A- Subject: What is connected to the "TUNING1" connector?
Solution: If you use Raduino in that connector nothing is connected.
B- Subject: Where does the 5-pin connector connect?
Solution: In the board version that I have the P3 connector is a long line of pins at the bottom of the Raudino. The 5-pin connector that has the DDS output, connects to the right end of the pin line.
C- Subject: Low bandwidth.
My first problem was that I found that my Bitx arrived only from + - 7200 to + - 7300 khz.
I had replaced the potentiometer that arrives from India with one of larger size and of common quality at low.
A multi-turn potentiometer in Argentina almost a third of what the Bitx40 kit costs.
I thought it was the potentiometer's fault or to use the original version of the Raduino soft. After updating the version on problem persisted.
Solution: The potentiometer wires were incorrectly connected.
D- Subject: The Arduino IDE does not recognize the Raduino board.
Solution: Install the CH341 chip driver and configure the board as "Arduino Nano" in the IDE.
E- Subject: SMD components "disappeared" due to a bad operation with a drill.
In a very bad practice, enlarge a hole in the cabinet with the Bitx40 plate in place. The perforation was parallel to the plate. I assumed that, since the perforation was millimeters high, nothing would happen. Error. The drill would cleanly start three smd mounting components. :O : O : O
Q1, C14 and D1 disappeared.
I really do not like surface mounts even that had made me doubt to acquire the Bitx40. If I wanted a hacking board but it had SMD components, it would be difficult for me to modify it. I never sold SMD components and had no trouble learning. But my imprudence forced me to solve the problem.
Solution: Replace the SMD components with discrete components. Instead of a BC849 I put a 2N3904. That was a feat for me and my poor eyesight.
F- Subject: I only received the audio from an AM radio. The frequency changed but nothing else was heard.
Solution: The Raudino DDS cable was connected to the PA voltage connector. Fortunately I do not connect voltage to the DDS input of Bitx40.
G- Subject: Where does the "FUNCTION" button connect?
Solution: Luckily this is very well documented. The FUNCTION button A button is connected to the orange cable (A3, the 4 cable) of the upper connector (P1). It is connected to the other end of the GND button, yellow wire, fifth wire of the P1 connector. This cable will also be connected to the tuning potentiometer.
H- Subject: Where does the "SPOT" button connect?
Solution: this is connected to D4 (Pin 22 of the Arduino Nano) this is in the lower connector (P3), It is connected to the other end of the GND button, yellow wire, fifth wire of the P1 connector. This cable will also be connected to the tuning potentiometer.