2m/70cm Diplexer

Ah okay.
That’s pretty much intentional.
I wanted to keep it clean and show only the actual filters, the bias-Ts are pretty much what you’d expect and its entirely optional for the actual functionality.

If you carefully read the Readme and click the schematic link, it should take you to the pdf of the full schematic.

Only it doesn’t because the links that work in my gogs do not work for kitspace.
Might need to talk to someone about that.

That’s cool.

So I don’t mind ordering my own board and parts, but is it the plan that a person would be able to purchase a complete kit directly through Kitspace? If so, do you have an ETA on that?

Not really, that’s not how kitspace works.

Selling real kits or assembled pcbs through some other kind of service is not worth the effort.
Even if somebody would take care of manufacturing and fulfillment for me, there’d still be some stuff like product liability, taxes, and e-waste regulation to be sorted out (I’m based in Germany so there is lot of legal stuff to consider).

Since the thing is open source anyway, I wouldn’t really mind if somebody else starts selling kits.

Gotcha. I was confused by the “kit” in the name I guess. Thanks again.

Alternate 144MHZ filter


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I know it’s been a while but I have one more update to this thread.

Finally I’ve managed to acquire a spectrum analyser to allow for some proper testing of my design.

Let’s see how close my hacky rtlsdr measurements from the last year were.

The 2m input and the 70cm input to the output (band pass and high pass):

The 2m input to the 70cm output (isolation between the two inputs):

Looks like my hackish measurements were surprisingly close to what the curves should look like.
So it seems that it is possible to do some basic filter design with just an rtlsdr and a cheap noise source from ebay.

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