There's
nothing like mounting parts on a new PCB design to make you a more practical
designer.
To the right is a picture of the module PCB, rev. 3. After loading it, I realized that the little bitty resistors I used for r4, r5 and r9 were just too small to work with comfortably. Of course, I wanted to use that size because I had lots of them, but I changed the PCB layout to allow the use of '1206' resistors, which are the same physical size as r7.
The other changes I made were to move r7 and d2 a bit towards d1 to leave a
little more clearance around the mounting hole just above d2; and I discovered
that the silkscreen for r1,r2 and r3 interfered with soldering to the RF input
trace, so I removed the body patterns for those parts from the silkscreen, and left
just the reference designators.
To
the right, you can see the intended connection points for R.F., power and the
PTT control line. Note that this example shows the input line connection point
bypassing the optional input attenuator, while the following picture shows the 3
chip resistors that form an aprox. 3db attenuator, and the way to connect the
input coax into it. Other resistor values can provide up to 10db or so using 1/2
or 1w resistors for r1 and r3. The resistors shown are 1/2w, but thick-film 1w
"2512" resistors are also available should you need to pad by that much.