Changes to FL? (just a brainstorm list – a place to keep new ideas as we go along)
Use 18F46J50 – compatible with 18F4550 (64K prog mem, extreme low pwr, internal RTC, I/O matrix)
Eliminate LCD backlite
Add programming ckt so we can use SMD uC  (still use ME programmer but can prog in-circuit)
Move to 100% SMD (allows room for sensor I/O, SD card)
Add voltage inverter to use –E30S LCDs
Heat sink recorder power regulator in case ON continuously for long periods in heat-of-day
Eliminate Master Reset switch circuit (just turn OFF and then back ON)
Add connectors for sensors
Cast alum case for heat-sink (same as current box but made of aluminum)
Slide on/off switch for easier assy
Add SD/SDHC card socket
Use on-board RTC of 18F46J50
Use batt with pins at opposite end of batt for mechanical stability
Use 1 cable assy for external connections (cable can be assembled separate from PCB on just plugged in)
Use blue PCB material to make more attractive front panel
Use recorders Sony PCM-M10, Olympus LS-5, LS-10, LS-11, Fostex FR-2LE  (Same prog will prob work with all of them)
Offer optional mic config:  Stereo or mono built-in, stereo or mono  external, Phantom stereo or mono, Ultrasound (Uses EM-158 no cap -good to 100kHz for bats)