Re: Testing Crystal Filters maximum dbm



You got to check the reading by looping in to out and see the reading. Adjust r20 to get
-20dbm on the display in SNA mode. It may be -10dbm and that flattens the plot top.
SNA and SWR dBm displayed readings are accurate +-1dB.

The SWR is also -10-12dbm (just checked a couple of boards) the open cal process
takes care of that.


At 27-10-19, you wrote:

Thanks Raj for pointing out that the output in the SNA mode is a safe -20dbm. What are the outputs in the SWR or PWR modes (I haven't used the PWR mode so far)? -20dbm would not deliver enough drive for the LO port of a typical passive mixer.

Attached you find an SNA test of a NOS 5.645Mhz Drake Blue filter matched with 1:9 Minicircuits transformers and about 10db attenuation. Not bad for a 50y old filter!!!

Il 23/ott/2019 05:41, "Raj vu2zap" <rajendrakumargg @> ha scritto:
> Current one too!
> Just connect a short cable between in and out and check reading on SNA mode. It should
> read -20dbm. If not change R20 to suit.
> Raj
> At 23-10-19, you wrote:
> >Raj,
> >
> >Are the production Antuinos affected or is it just the early ones sold at Hamvention?
> >
> >73, Mike KK7ER 

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