[Test-Equipment] Waveguide question

[J. Forster]

Check and see if the amplifier's output is protected internally with an isolator. If it is, you're likely fine. If not, put an isolator between the amp and the WG launcher, as close as possible to the amp. BTW, be SURE your connectors are good quality and are not damaged.

-John


Scott Schappert wrote:

> G'day to the list.
>
> This may be slightly of-topic, but I have a question about coupling an
> RF amplifier to a waveguide transition:
>
> I have an 8-12 GHz solid state source to an 8-12 GHz wideband, solid
> state 1 W amplifier.  I want to launch the RF directly from the output
> of the amplifier to a WR90 waveguide transition.  All connections on
> instruments are 50 Ohm "N" type connectors.
>
> I am concerned for the amplifier because the Z-zero is 50 Ohms output
> into the infinite Z-zero of the waveguide.

What makes you think the Zo of the WG is infinite? If it's properly matched and terminated and operating in band the Zo is about 50 Ohms.

> I have used other amplifiers
> where the output is directly coupled to a waveguide flange, but never
> tried it on my own.  I do not want to damage my amplifier from mis-match
> on the output.
>
> I would be very grateful to hear from someone who might be able to let
> me know how to approach this situation intelligently.
>
> Best regards to all,
>
> -Scott