On Thu, 2007-08-02 at 09:34 -0700, Kevin Anderson wrote:
> The Jones filter in the Scout and in the Argonaut/Delta II,
> while both Jones filters, are similar, yet very different
> animals.
>
> The filter in the Scout, which I am familiar with, has a fixed
> center frequency and is only adjustable in width. To make the
> filtering even more impressive (in my opinion), the center
> frequency is set appropriately (or they adjusted the filter
> shape somehow) to provide particular filtering of the opposite
> sideband/carrier frequency. The eight crystals of the Scout
> Jones filter are set up as two parts, with five crystals in a
> fixed filter, and the remaining three crystals used for the
> variable part.
>
> The Jones filter in the Delta II is different. While also a
> Jones filter, the ability to adjust the passband center makes
> this version a very different animal. For me, adjusting the
> Jones filter was frustrating, the one time I used one, to say
> the least, as I continually having to adjust both the center
> frequency and width. After an afternoon of using it, I never
> did find the magic combinations to kill opposite sidebands, etc.
> What made things particularly challenging was that I was
> operating at friend's house in a contest, where I was
> alternating back and forth between times operating with CW and
> with SSB, each of which required different settings of the Jones
> filter. Eventually I gave up and ran the filter wide open,
> depending on my ears to do the filtering.
>
> I agree that the use of the Jones filter in the Scout is a very
> efficient, yet effective, filter for that category of radio.
>
Thanks Kevin for that bit of info. I was not aware they are different in
their respective radios.
I'm sure we all learned from this useful information.
Good show!
Ron, wb1hga
(I got the name right, this time) smile
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