Center Zoom capability

W4YXU

A suggestion for this topic: Make zoom in/out center on current baseline and frequency. I think this is what most are trying to do with zoom! Note: This topic was created from a reply on the Panadapter waveform below bottom of display topic.

Ken - NM9P

Or at least make it a check-box option.

Eric-KE5DTO

Note that you can zoom the Panadapter display in and out centered at a particular frequency by Left Click and Dragging in the margin at the bottom of the Panadapter. We hear you on the noise floor moving around as you zoom in and out. This causes the user to need to adjust the vertical adjustment with each zoom click. One solution to this might be to move the lower limit on the vertical scale whenever the FFT must be changed to facilitate the zoom. Would anyone object to this? This means that as you zoom in, the bottom of the Panadapter might go from -130 to -133, -136, etc. Then it would move back up as you zoom back out. This should keep the noisefloor in view no matter the zoom level.

Ken - NM9P

I would like to be able to put the bottom end of the pan where I want it and "Drag" to zoom the right end in and out without it moving the bottom end so that I can set up my bad limits within the pan without constantly having to "drag the scale, drag the pan, drag the scale, drag the pan," in order to get it just right. For example... I would like to drag the pan screen at the low end to 7.125 Mhz and set the bottom of 40 SSB, then drag the scale on the bottom until the right hand of the display zooms to 7.130 Mhz, leaving the low end at 7.125 Mhz. Right now it takes me about 6 or 8 operations to get the display zoomed and centered just the way I want it. I like the idea of having the "click" buttons be able to zoom on center of the trace. If we could have both options, I would be happy. I would also like to have the choice, when tuning near the edges of the screen with my Flex Control Knob to have it NOT begin a shift of the pan screen whenever I get within about 10-15% of the edge. This is frustrating to me. BTW, I notice that if I use DDUtil to control the Knob, that the screen does NOT sift the pad as I tune to the edges, but when the Knob is connected directly, it does move the pan screen.

Eric-KE5DTO

Do you mean that you would prefer the option to tune the Slice off the Panadapter?

Ken - NM9P

Not exactly, but now it seems that if I get within about 10-15% of the edges it starts moving the pan screen, even if I am not going very far. I never now exactly how far I can go before it starts shifting my display, then I have to drag it back.... The sections of the pan display that I cannot tune without shifting the display to the right or left become essentially wasted space because I cannot "use" them without disrupting my display. This will become even more of a problem when you implement waterfall or panfall. Perhaps changing the edge limits the tuning know must reach before it starts panning the screen would help. (or give me an option to set the % limits?) Or perhaps only pan the screen if I actually get to the edge of the screen, or come to within 2% of it?

Robert -- N5IKD

I am good with SmartSDR keeping the noise floor visible as I zoom. Ideally it would keep the noise floor stable as you move it so that if I start zooming the noise floor will not move whether I have it in the center of the screen or off the bottom of the screen. As for the zoom function itself (and all other functions) I would like to be able to use the keyboard. I can make adjustments much faster and more efficiently with the keyboard. Zooming in and out could be done with the numeric keypad +/-. Fine tuning the slice could be done with arrow keys.

Ken - NM9P

Yes! Some programmable keyboard shortcuts would be very nice. Such as PgUP/PgDN for Zooming the pan, PgUP/PgDN for Zooming the scale (like zooming the right scale buttons) , Lft Arrow/Rt Arrow to tune, etc. And I forgot to comment on the stabilization of the noise floor... I would like to see it automatically adjust according to a formula for initial setting upon zooming, whether by dragging or clicking the buttons. But we should be able to override/adjust it ourselves after that until the next zoom operation.