Ground Plane construction vs pre-printed "protoboards"
For years I designed my boards in a time consuming way. I used
Microsoft paint to draw the pattern. I printed this pattern on clear
piece of 3M transparancy using my copy machine at work. Later I used my
home laser printer. I cut and cleaned the board like Richard Hosking
suggested. I then ironed the pattern on the PC board using a home
cloths iron. I used doubled sided PC board. I have always surface
mounted all my parts even leaded types. I used the lower side of the
double sided board as a ground plane drilling holes only to attach
ground leads below. I also placed as much ground plane on the surface
of the board as possible.
This method always worked well but I must qualify my building as being
between 1.8 and 30MHz, nothing higher. In the last 7 or 8 years I have
gone to Ugly construction. I read a quote attributed to W7EL Roy
Lewellen about ugly construction years ago. The method I used was time
consuming. I could save patterns for reuse and dupication but the whole
classic PC board process is time consuming. I tried Roy's suggestion
and never went back to my time consuming process.
My first project years ago was updating a drifty 40M VFO. I measured
the drift in the old VFO to 200 cycle/hr after 20min warmup. The new
VFO using ugly construction measured at 20 per hour after warmup. Both
used the exact same circuit, roughly the same component values but
different manufacturer so the comparison is somewhat flawed. Recent
projects using ugly construction: An new HB RF signal generator, 6W
sideband transceiver, logarithmic RF detector and a 1.7 to 1.85MHz LO
for a new sideband transceiver. This new VFO drifts 10 cycle/hr (47
cycles over 24hr) but is still open to the environment on the
workbench.
I have used ugly construction in tube rigs, VFO's, high gain audio
sections of DC receivers, test gear, etc. The one thing that makes it
appealing is the ability to test a circuit or idea without going into
the long process of PC board prep. The ugly method is intuitive and my
opinion...damn the appearance....does it work well!
Don K5UOS
PS John Miles' receiver is amazing! Wish he lived near me.
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