On a sunny day (24 Sep 2006 07:20:57 -0700) it happened "Telstar Electronics"
wrote in
. com:

Jimmie D wrote:
Point to point wiring does not have to mean the birds nest constuction you
describe. RF wiring could well be stamped out metal pieces mounted on Teflon
or ceramic. very repeatable, very stable. It could also mean the isolted pad
constuction where smalll sqares of PC board are glued to a substrate. This
has proven reliable, obviously an improvement over PC board material could
be found.and better mounting methods than glue.

Yes, I agree with you. The problem is that these amp builders are not
using the point-to-point methods you describe. From what I can see...
they are gluing pieces of copper clad board (via double sticky tape) to
a non-etched copper-clad board. They have no regard for characteristic
impedance of trace widths
(http://www.pcb123.com/help/calculators/microstrip.html).

At 27MHz 50Ohm this is not critical.


I also am not
really crazy about the longevity of double-sticky tape... LOL

Maybe it is epoxy glue, how would you know.

Agreed, my new amplifier design
(http://www.telstar-electronics.com/S...202879ABTC.pdf) now has
thermal tracking class AB biasing.

Yes that is good.

I also don't use any front-end
attenuators. Like you say, proper setup is critical to any good
station. The operator needs to pay attention to the drive requirements
of the amplifier... and should adjust the driver accordingly.

There are many sets on the market, somebody will drive it with too much,
and somebody else will drive it with too little.

Tough world out there.
;-)

www.telstar-electronics.com