In article . com,
wrote:

On Nov 3, 5:49 pm, Telamon
wrote:
In article .com,

wrote:
If you need to prototype or build a lumped element RF filter, check
out the RF Filter PCBs at RF Bites.

http://www.rfbites.com

Those are not very good coax to PCB connectors. You can do better. Must
be pretty low frequency stuff ( 1 GHz ) if you are using FR4.



So, what material do you use over 1GHz?

Commercially you could use Rogers materials. A good step over FR4 would
be Rogers 4003. More expensive that that would be Rogers 5880.
Comparable to Rogers 5880 would be 25N Arlon.

You buget guy must really not like you.

The bean counters don't like me at all.

BTW, I didn't design these boards, nor to I work for these guys. I
just got my board in the other day and was pumped up when I was able
to build up a filter quickly. It's in my tuner right now, filtering
away. My filter has good rejection (50dB) up to 3.5GHz, and it
starts to fall apart.

Your insertion loss will not be good over 1 GHz. Sure the filter will
work over 1 Ghz.

If you have a fast enough TDR you can see that that connector is very
capacitive looking where the pin is on the board and the return losses
will not be good. Since you use them on both ends of the board you will
get reflections between them.

The footprint for the connector is as important as the connector itself.

--
Telamon
Ventura, California