1, the audio input signal amplitude can be adjusted, VR1 and VR3 to change the input signal amplitude2. This board is not a preamplifier and has no power amplification. It only uses the way of fluorescent column to show the change of the amplitude of the audio signal, so that the audio signal is changed from auditory to visual (visual effect).3. The parameters of the two tubes are inconsistent due to the individual differences of the 6E2 tubes. After the lighting, the fluorescence of the two tubes are not the same. Therefore, two trimming resistors are set on the driving board, and VR2 and VR4 are used to adjust the fluorescence height of the left and right tubes to achieve Highly fluorescence of the two tubes4. Pipe connection: The extension of the socket pin has been soldered out, and it is connected to the corresponding terminal number of the driver board according to the color of the lead wire (the delivery is accompanied by a wiring instruction)5, the base is made of universal small nine-legged tube ceramic tube front mounting hole distance 28mm, panel opening: 18mmPCBA wiring: ainR / ainL: left and right channel audio signal inputG: ground250V: (DC),Left and right terminal block serial number and Connect the gate, (6E2 tube signal injection pin) to the socket 1st pinconnect the cathode, pipe grounding foot, take the third leg of the socketconnected to the control grid, used to control the fluorescent height of the tube, the seventh base of the socketconnected to the anode, 6E2 tube power supply feet, take the 8th foot of the tubePins 4 and 5 of the header are filament supply pins (6.3V supply)Note: The two tubes are connected in parallel to the 6.3V power supply Two tubes of filaments are connected in series to take 12V power supply Note: The 100K position of the DIY kit welding resistance should be 120K.Colour:As ShownMaterial:PC+metalPackage Contents:1 x 6E2 tube indicator driver board kitOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.