August 12, 2013-

PCB layout/fabrication update:
The PCB layout was slightly updated and the drill file was updated.  The
earlier drill files had multiple drill hits at identical locations.  That
could break drill bits on automated drilling machines.  A Perl program
was created to eliminate those multiple drill hits to the same location
and was then run on the "drill.drl" file.  The multiple drill hit problem
comes about in FreePCB routing when dealing with multilayer layouts and
the user doesn't fully understand what he is doing! ;-)


November 30, 2012-

FT301D Replacement Display Version A03

Hardware:
The FT-301D Replacement Display version A03 is only a slightly newer
version of the design.  The main changes were to clean up some CAD tool
library discrepancies.  In particular, the pinout of the SOT-23 devices.
The older versions of the design were consistent and correct between the
schematic and the PCB layout (in other words, things worked), however, the
pinout for the SOT-23 devices was not in the industry standard arrangement
for pins 1 and 2.  While making those changes, a few other devices in the
design were updated to SMT (4.7V zener diode and 1N914 diode).  Also,
various part numbers were updated to the latest most cost effective parts.
Also, the layout report file now contains valid data for all devices
(library parts "0805", "SqPin1x7", "SqPin1x8", "DO41SMT" were updated
so they would report correct position data in the report file).

Firmware:
The revision level shown in the firmware files was updated to show "A03".
This firmware is not changed from the previous "A02" version, however, if one
had not upgraded from the initial first version "A01" of the firmware, then there
are two changes that will be noticed.  First, the JJY/WWV switch position
will now show a fixed frequency of "5.000.0" (ie., the display will reflect
the fact that the JJY/WWV frequency is fixed and tuning the VFO does not
actually change the frequency being listened to).  Also, when one selects
a "fixed frequency" crystal postion that is not populated, the display
will have dashes displayed (eg., "14.---.-") instead of a bogus frequency.

PCB layout/fabrication note:
The board layout is done as a 4 layer board.  If you have lots of $$,
you can fabricate it that way.  However, my fabrication method was to do
it as a 2 layer board (top_copper and bottom_copper) and then use
jumper wires for the traces shown on inner copper 1 and inner copper 2 in
the CAD files.


73!,
Paul
WA7ZVY

