Not so, Saandy. He said STRIPLINE, not microstrip. Now he may not know the
difference, but that is an incorrect value for stripline.

WHich is it, microstrip (open face) or stripline (sandwich)?

Jim



"Saandy , 4Z5KS" wrote in message
ups.com...
1.2mm on G10 , 1,6mm thick glass epoxi board will give you a Z0 of 75
ohms from DC to daylight.
Saandy 4Z5KS

what's the difference?
Is "open face"on a singlesided pcb and "sandwich" on a doublesided pcb?
I use a doublesided pcb with one side as a groundplane.

tnx, Wim

No. Microstrip is the transmission line on one side of a double-sided PCB
and the ground plane on the other side. Stripline is with TWO PCBs with the
transmission line sandwiched on one of the boards and ground planes on BOTH
the outside layers. It makes for a much improved shielding at the expense
of much more complex mechanical assembly.

Jim



wrote in message
ll.nl...
what's the difference?
Is "open face"on a singlesided pcb and "sandwich" on a doublesided pcb?
I use a doublesided pcb with one side as a groundplane.

tnx, Wim

wrote:
what's the difference?

You should do some homework,
http://www.ansys.com/industries/mems..._micostrip.pdf

or in a shorter format

http://tinyurl.com/dxtvu

Cheers,
Galen, W8LNA

Thank you all for your input and help!
Now i can live on

73, Wim PE1PME

forgive him, not me would you care to hang a mosquito on a piece of
strip line. It's quite clear he's referring to a microstrip circuit.
which one of us is using strip lines, except in power amplifiers.

You wanna try that again in English?

Jim


"Saandy , 4Z5KS" wrote in message
oups.com...
forgive him, not me would you care to hang a mosquito on a piece of
strip line. It's quite clear he's referring to a microstrip circuit.
which one of us is using strip lines, except in power amplifiers.

Oh, well, those of us who deal with multilayer boards regularly use
stripline: lines sandwiched between ground planes on inner layers. But
from the sounds of it, Wim almost certainly is using microstrip.
However, if you look more carefully at it, you'll discover that your 75
ohm line is NOT 75 ohms "from DC to daylight" -- things fall apart at
low frequencies (significantly so below 1MHz or so), and where the
dimensions of the line are comparable to a wavelength (well below
"daylight"). But again, Wim should be fine using the dimensions you
originally gave him for what he wants to do.

Cheers,
Tom