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Old September 25th 06, 10:54 AM posted to rec.radio.cb
Jan Panteltje Jan Panteltje is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 54
Default Amp Design Concept -- Preliminary

On a sunny day (24 Sep 2006 16:47:45 -0700) it happened "Telstar Electronics"
wrote in
. com:

Jan Panteltje wrote:
So we ask him again: What values did you enter, and what dielectric constant
for the PCB material and 'tape'.


You are getting to be a real pain in the keyster... LOL


We wil get you to publish the diagram too ...:-)

I use 0.062" 1oz FR4 for my designs.
The dielectric constant of FR4 is about 4.6
Thickness of 1oz copper is about 0.0014"

So with a ground plane on one side of the board... the width of the
trace to maintain a 50 Ohm characteristic impedance is about 0.113"
wide.


OK, now you have a 50 Ohm track, and *where* do you put it?
The only place you could possible use it is to the output connector,
and that connection happens to be a *wire*.

Have a look at those pictures again, the extra PCBs you were _originally_
referring to as needing that website calculator, are just simple solderpads.
The rest is normal wiring.

P.S. Have no idea what tape you're talking about...


The double sided tape you accused them of using to glue on those extra boards
that are used as solder pads.

And, I have to say that .113 inch equals around 3mm width.. your transistor
connections and the stuff they are soldered to on your board are wider..

But you score on one point, you caused 2 more posts on the subject of
'Telstar amp'.

You can score a *lot more* reactions by publishing the diagram, people
will have questions and suggestions and maybe even [positive] critism
if you do.
So let's have it OK?
You are no chicken to show it no? It is free of flaws I am sure?
Come on Brian, it is not THAT different from the appication notes now is it?