Re: Automatic bandswitching for WA2EBY Filter

K9HZ <bill@...>

Well the best and most reliable way is a BCD band connection from the xcvr. You can create a frequency counter and look-up table easily, but the trick (so ive found in building these commercially) is to determine WHEN to count and WHEN to switch. There are a number of rules to use to simplify this but its not as easy to implement as it sounds. 

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ


Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois


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Villa Grand Piton - J68HZ

Soufriere, St. Lucia W.I.

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On Jan 20, 2018, at 9:11 AM, Gordon Gibby <ggibby@...> wrote:

If you wanted to use an arduino nano to do automated bandswitching of the low pass filters in a WA2EBY type amplifier (and possibly also automated attenuator input pad adjustment), 

what would be the best way to gauge/measure the input band?

1.  some sort of frequency counter?   maybe some already built thing from ebay?

2. some sort of system developing two analog voltages, one related to peak input voltage and the other through a low- or high-pass filter giving a different analog voltage based on input frquency, divide the two to figure out what band is in use?

3.  maybe some output from the ubitx (if you're using a ubitx)?

Any suggestions from the gurus here?   It would really be nice to have automated bandswitching on this sort of amplifier.


gordon gibby

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