STEP 9: Solder a 1.0” to 1.25” length of wire on the solder pad connections of the PCB.
VU-1MK500 Installation Guide
The VU meter only needs (3) wires to get it working. Look at header J1.
1. The first pin is labeled “IN”. This is connected to either pin2 or pin3 of the XLR output jack.
2. The second pin is labeled “GND”. Connect this to the GND of your Power Supply.
3. The third pin is labeled “V+”. Connect this to the Positive Terminal of your Power Supply.
Voltage applied to this pin must be b5VDC to +25VDC.
If you’re using the VU meter kit with any of the FiveFish Mic Preamp Kits, solder the VU meter’s IN,
GND, and V+ wires to it’s corresponding pads on the Mic Preamp PCB.
VU-1MK500 Calibration Guide
1. Adjust trimmer resistor so that when you feed a 0dB signal to the VU Meter, the 3
rd
LED lamp
lights up.
For +4dBu operation, connect a signal generator to the VU meter input, 1Khz, adjust output of
Signal generator to 1.22Vrms, and adjust trimmer resistor until 3
rd
LED lights up.
VU-1MK500 Troubleshooting Guide
Well, hopefully you won’t need this part.
“Measure twice, cut once”… as they say. Take your time assembling the kit, don’t be in a hurry, work carefully
and methodically and you won’t need this troubleshooting guide
Problem: No lights, no LED movement. VU Meter does not work!
Check if there is power applied to the VU Meter Kit. Supply voltage must be at least 5Volts DC. Check the GND
wire is connected.
Also check that the “IN” pin on Jack J1 is connected to your XLR jack. You can connect it to either pin2 or pin3
of the XLR output jack.
Check that the LEDs were inserted in the correct orientation. Long leg soldered to the left side.
Check that you installed the jumper headers for JP1, JP2, JP3 and JP4. All jumpers must be either in the HORZ
position, or VERT position. Do not mix and match.
Check that the trimmer resistor is adjusted.
