The main board has an array of panel illumination LEDs, to make it easier to see the button locations in a darkroom environment. These LEDs shine through small holes placed adjacent to the panel buttons.
The early prototypes used the Lite-On LTL-4225, which are somewhat standard T-1 3/4 LEDs. They worked, but were slightly too tall to comfortably fit in the space between the top of the PCB and the interior surface of the enclosure. Whether or not they fit, is way too dependent on manufacturing/assembly tolerances.
The more recent prototypes switched to using the SunLED XLUR11D. These are smaller T-1 LEDs, which require spacers to achieve the desired height for being close to the interior surface of the enclosure. While this option works, adding the spacer involves an extra component and an extra manual assembly step for each LED. It would be best to avoid this, if possible.
The current proposal is to switch to the Lite-On LTL-10223W. This LED is closer in size to the original choice, a little bit shorter and without a flanged base. Making sure its aligned correctly during soldering may depend a bit more heavily on a positioning jig, but should still be possible. Its specs are also similar to the original choice, but with a wider viewing angle. Its possible there will be a bit more spill from its light, so that should be tested to see if that is even a concern.
The main board has an array of panel illumination LEDs, to make it easier to see the button locations in a darkroom environment. These LEDs shine through small holes placed adjacent to the panel buttons.
The early prototypes used the Lite-On LTL-4225, which are somewhat standard T-1 3/4 LEDs. They worked, but were slightly too tall to comfortably fit in the space between the top of the PCB and the interior surface of the enclosure. Whether or not they fit, is way too dependent on manufacturing/assembly tolerances.
The more recent prototypes switched to using the SunLED XLUR11D. These are smaller T-1 LEDs, which require spacers to achieve the desired height for being close to the interior surface of the enclosure. While this option works, adding the spacer involves an extra component and an extra manual assembly step for each LED. It would be best to avoid this, if possible.
The current proposal is to switch to the Lite-On LTL-10223W. This LED is closer in size to the original choice, a little bit shorter and without a flanged base. Making sure its aligned correctly during soldering may depend a bit more heavily on a positioning jig, but should still be possible. Its specs are also similar to the original choice, but with a wider viewing angle. Its possible there will be a bit more spill from its light, so that should be tested to see if that is even a concern.