开云体育

Tom:
So, for the time it takes the hardware to figure out what frequency you
are at you maybe out of compliance until the filter switches?

Howard

On 8/13/2018 1:17 AM, Tom, wb6b wrote:

Hi,

I wan't to build a filter I can use with the uBITX. However, I don't
want to build a filter that is strictly tied to the uBITX.

So I'm building a standalone Low Pass Filter box that will work as an
add on filter for the uBITX as well as become a general purpose piece
of Ham equipment I can use over and over for other needs.

It uses an Arduino to measure the frequency you're transmitting on and
select any individual or combination of filters you like. The proposed
design uses a set of filters and a relay switch board; such as to ones
by QRP Labs. But, the Sketch code should be easy enough to modify for
whatever you like.

The controller can show he selected filter with LEDs or with an
optional LCD display, and show the transmit frequency as well.

I'll need to order parts and build mine to finalize the design.
However, I built and tested a prototype with a signal generator.

I'm releasing the preliminary design to everyone now because it is
complete enough for people to try out on their own filter designs. It
makes using outboard filters really easy, and I think people will like
it. I welcome feedback on improvements people make while building
their own "Auto Filters" with the controller.

The code for the controller is
here:


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Tom, wb6b