ADC Analog to Digital Converter,
DAC Digital to Analog Converter,
set them to-high "create noise on the line" to/from the DSP,
set them to-low a "cause image refreaction" on the line to/from the DSP,
same with AGC Automatic Gain Control
0 to +1 have been observed to offer "best performance" for "most" Phase II systems on all three settings.
Decode Threshold is like a Digital Squelch setting for the scanner, for the scanner to understand what conditions "it should use" to move onto (or look for) the next site (and/or tower).
75-99 is perfect for: perfect none mobile conditions,
15-85 is for more imperfect mobile and extremely windy days,
50-90 is for lightly breezy days and none mobile, roam conditions.
1 barely any signal at all, if any.
99 Perfect
DSP changes how the signal is processed, quicker adjustments higher, slower lower, 72 is "somewhat more ideal" for Phase II
Now several members will constantly say this or that but offer no solution, until we take a survey and find what users use across the country use, we will never know. Hence, why firmwares are adjusted by manufactures and number may change between models but these should be used as "starting points" and "guidelines", not absolutes.
Many members just don't want to give up the valuable info they have learned for whatever reason.... Constantly seeding misinformation and just like they use to, with frequencies
Do let the fools play you about purchasing SDRs and Professional radio BS, none is more affordable or as convenient as a scanner, you need at least 1000 radios and 3000 dongles to compete with a PSR-800 ability to listen to the same amount of SYSTEMS.