Yes. When I commented "clean" the copper from beneath the inductors, I
imply no copper beneath the component(s).
Yes, that will introduce a slight impedance bump in the line. However,
even a bit of solder will do much the same. This becomes even more
critical with increasing frequency. Consider the length of even a small SM
component. Both the lands on the PCB to mount the device and the "bulk" of
the component contribute an impedance bump. Be thankful you're working at
915 MHz! My radio astronomy preamps are a challenge at even 1.42 GHz and
becomes worse as I go upward in frequency.
Dave - W?LEV
On Wed, Mar 19, 2025 at 2:09?AM Nico via groups.io <nicolassimard=
[email protected]> wrote:
Dave,
That's very interesting. That is what I came across the datasheet of the
capacitors I bought. Look at the picture, I think that's what you're
talking about. Unfortunately, it is not mentioned in the inductor
datasheet.
I tried it out tonight. Unfortunately, The match get worse (no as worse)
but in the same direction as when I've put the inductor. I didn't have an
18 gauge on hand though, only 22AWG.
When you say "clean" the ground plane, do you mean that below the
footprint occupied by the inductor, there should have no ground plane in a
"copper at all" beneath it ? In this case, doesn't it creat a return path
discontinuity for the transmission line ? I've attached a picture for
clarity.
Thanks
--
*Dave - W?LEV*
--
Dave - W?LEV
