6600M bandwidth center/width controls

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  • Updated 2 months ago
When the 6600M front panel filter controls are put into the "width / center" mode, the filter bandwidth collapses to zero bandwidth if the center frequency is moved toward the carrier frequency so that the one edge of the passband moves through the carrier frequency.
I believe the once the passband width is set, you should be able to move it around without it changing.   The controls work as expected in the "high / low" mode.
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Geoff - W8GNM

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Posted 8 months ago

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Rich McCabe

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Wonder if your knob inner and outer ring is too close and turning both? Several guys have had issues.
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Geoff - W8GNM

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Rich, no the knobs are mechanically fine and work perfectly in "high/low" mode.
This problem only occurs in the "shift/width" operating mode entered by pressing the outer knob in to switch modes.  I think it is a software issue.
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Rich McCabe

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So is this in CW mode or another mode Geoff?  I assume you meant to say press the inner knob in to switch modes and not outer?

On phone it collapses the width when it gets to the carrier frequency and does not cross it.  You would think it would just stop.  I have never had a use for that filter mode in phone though.

Rich
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Geoff - W8GNM

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In SSB mode.  I haven't tested it in CW mode yet.  When I said outer I meant the one sticking further out  from the front panel.  You are right it is the inner, concentric, knob that changes the mode between "low/high" and "shift/width".
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Rich McCabe

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Geoff, you might be a good guy to explain to me why you would use this filter mode in SSB?  I find it frustrating that Flex does not associate the filter mode type with the mode.

 It seems to me that center is a method for tuning modes with a center carrier like CW and AM.

I would agree that it should not change the width when you hit center but don't understand why you would want to use this mode on SSB anyway.

Rich
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Geoff - W8GNM

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Rich, sometimes it is more convenient to set a receive bandwidth for SSB and then be able to slide this bandwidth window slightly up or down in frequency to eliminate QRM from above or below this frequency window without having to individually adjust the upper and lower frequency limits.
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KC2QMA_John

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Is there a way to make the RX filter controls default to LOW/HIGH instead of SHIFT/WIDTH?

I find that I mostly use the LOW/HIGH feature of the bandwidth controls most of the time and would like that to be the default mode instead of having to press and hold the button every time I use the radio to switch from SHIFT/WIDTH to LOW/HIGH.