On Tue, 28 Feb 2006 20:35:01 -0600, Bob Bob wrote:
I suspect there is also another issue whereby the resonant sensor
section is actually absorbing more power than it should and dissipating
it in the resistor.

Hi Bob,

That is why it is there, among other reasons.

The effect of this being a loss of available output
power at the SMA connector.

This is a symptom, and should not be a cause.

To answer you specifically Richard, the PCB is a multilayer fibreglass
thing with a largish ground being under both the output and sensor
striplines.

That is as it should be.

I was surprised that the sensor line was so long and so

On the order of 1.5 cM?

close when I first saw it thinking some major overcoupling might be
occurring. The tracks are maybe 3mm wide and about 1.5mm (edges) apart.

Sounds like a boilerplate design - which is to say right out of some
book or App. Note.

I am thinking also that the 50 ohm output is not being preserved as it
goes past the sensor stripline.

What does that mean?

I think the freq coverage for this model
is about 10.5 to 11.5GHz. Keep in mind that this really is the frist
time I have seen microwave TX's up close so my gut feelings about track
sizes/spacing may be way off.

Check the resistor.

73's
Richard Clark, KB7QHC