Release Notes: AA908_v4.0a
Date: 11/15/2004

This newest software should be used once the Service Pack has been installed.  It depends on proper channel gain with the ERA-3 amp on the DDS card, and with R19,R24,R29,R51 = 71.5K.

Changes since v3k5 ...

1) Changed to using ERA-3 with different gain resistors.  Getting rid of MAV-11 solved
high-end signal level rolloff

2) Changed to "back_to_basics" simplified calibration, adjusting Vr to make SWR=5.4
with 270-ohm load.  Best performing results ever!!

3) Added LCD backlight control circuit (and software timers, Setup menus, etc.)

4) Fixed bug in calculating R (was improperly scaling large denominator)

5) Started measuring and adjusting for A/D offset voltages.  Improved accuracy a bit.

6) Now handling remainder of correction factor generation and use.  Yields best results yet!

7) Fixed cursor adjust too far to left.

8) Straightened out Lite control and EEPROM save/restore

9) Moved cal data to EEPROM Page 1.

10) Fixed power-on pushbutton so timing not critical on release.

11) Added "Stopped" display at powerdown.

12) Made the Default Settings option more sensible and usable.

13) Determine & display reactance sign.  (I'm still not happy with this and more changes will come.)

14)  Reactance Sign Determination -- I diddle the freq (by 1 MHz!) when the 
instrument is in Impedance Mode, and when the dial is at rest.  You can see 
this on a scope connected to the load.  Kind of interesting, actually.

15)  L & C Measurements -- Press and hold the Mode pushbutton until you see 
the desired measurement, then release the pushbutton.  Display shows 
frequency on 1st line, and specified measurement on the second.

16)  VFO Mode -- I added a fourth mode called "VFO" which just outputs the 
test signal, without diddling, yielding a signal suitable for external use.
