Tools And Construction Hints - NORCAL NC2030 Manual

Tools and Construction Hints

There are many great articles on the web that describe techniques on building surface mount projects.
Alas, I am guilty of often using a bit too much solder. Rather than right my own version of this, let me
repeat some of these links:
www.geocities.com/vk3em/smtguide/websmt.html
www.seed-solutions.com/gregordy/Amateur%20Radio/Experimentation/N2PKVNA/SMT.htm
www.piclist.com/techref/smds.htm
In building this transceiver myself and creating the manual, I have had some problems. These fall into
four different categories:
1) IC pins not really soldered
2) ICs mounted backwards
3) Resistors and capacitors not soldered to the right set of pads
4) Not all parts were installed
Between testing prototypes and building the final transceiver, I have built five of the NC2030s. Please
learn from my mistakes. Each time an IC is mounted, check the mounting polarity twice before
soldering it in. I suggest checking the IC polarity, soldering down one corner pin, and then checking it
one more time before finishing the job. I think the old saying is "measure twice, cut once".
I have several times mounted caps and resistors to the wrong set of pads. This problem can be corrected
by mounting the resistors first, double checking the resistor placement and values against the pictures,
and mounting the capacitors after all the resistors are mounted. The assembly instructions have been
modified to reflect this order.
The resistor values can normally be read from the pictures included. "473" is a 47000 ohm resistor, a
"271" is a 270 ohm resistor, and a "332" is a 3300 ohm resistor. The last digit is the number of zeros
after the first two digits.
I have once been bit by not mounting all the parts. This is pointed out in the LO mixer section. I forgot
some frequency selective resonating caps, which caused the LO mixer to have very low output. Please
print out each section as you go and check off the parts as they are mounted. The pictures have been
made of the 20m version of the transceiver. The 30m version can have a slightly different combination
of caps in the frequency sensitive areas of the board.
Lastly, I have had IC pins that look soldered, but are not. This happens when the top of the lead of the
part gets soldered, but the solder does not extend to the pad. On my first NC2030, this happened a few
times until I figured out a trick to make sure that all pins were properly soldered.
Norcal NC2030 v5 12-18-05
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