48V PHANTOM POWER INDICATOR LED
By default, the DIY500 mkII front panel has a small hole drilled next to the 48V phantom power ON/OFF switch. If present, we can use this hole to install an optional indicator LED to let us know when phantom power is ON and present.
Remember that for ease of assembly components should be installed in ascending order of height. Granted, we are installing this LED now – after the resistors and before the switches – because it is the next shortest component, and resides on the bottom of the PCB.
Also, please keep in mind that this LED (standard 3mm diameter) is: 1) polarized (pay attention to orientation!), 2) will be the only component installed on the bottom of the PCB, and 3) requires the presence of resistor, R24. One method of installation is described in the following photographs.
Fig. 27 a) Determine the LED polarity: the square PCB pad is (+), which is the side of the LED with a longer leg and rounded base flange, and the round PCB pad is (-), which is the side of the LED with a shorted leg and flatted base flange. b) Determine the length at which to bend the leads (legs). You want the LED base flange to be flush with the edge of the PCB.
Fig. 28 Bend the LED leads to length at a right (90˚) angle.
Fig. 29 Insert the LED from the bottom PCB layer as shown, and solder its leads in place on the top PCB layer.
Fig. 30 Once soldered, trim the excess LED leads.
Fig. 30 Very good! Proceed to the next step.
