Re: ubitx cw listening width modification
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The ubitx is quitr hackable that way. Here is a hack. You take the signal off from both ends of the crystal filter and add a parallel one, say at 1.8432 mhz. This will provide a very narrow cw filter. Now, all you have to do to switch the filter is change your second if to 45 mhz + 1.8432 mhz. viola! narrow band cw
On 17 Dec 2017 8:16 am, "Gordon Gibby" < ggibby@...> wrote:
Hi Brien --? ?
The filter width is set by a crystal filter.? ?The Raduino? (Arduino-controlled VFO)?does not produce the audio signal, so I don't think you would be able to introduce an audio digital filter within it.? ?
You could add an audio filter to the output (digital or otherwise)? or you could electrically alter the configuration of the crystal filter that sets the bandwidth.? ?My BitX40's only had 4 cystals (quite fewer than the uBitx) and appeared to me to have
a narrower bandwidth.? ?It is possible that you could use capacitors or wiring to bypass (or "pull" with capacitors/inductors) some of the cyrstals in the filter to make it narrower.? ??
That's the limit of my knowledge, perhaps others will offer better solutions.? ?
Thanks!
Gordon?
In my quick read of the circuit description it says the same width for listening to SSB and CW, but that there is no reason the Arduino code could not be altered to provide a 500 hz bandwidth.
That would be absolutely required for me... I realize this is a fairly reasonably priced kit for what ALL it does, but I am very used to using 600 hz for general tuning around and? narrower at around 500 or 400 for QSO operation... if not narrow sometimes
in regard to band congestion... so am interested in what the CW ops might say on this topic re. operation.
Brien
VE3VAW
Toronto ON Canada
---------- Original Message ----------
From: Doug W <KD9CYF@...>
Date: December 9, 2017 at 5:28 PM
Thanks for all your work Ashhar.? Just ordered mine.
I don't know if it aired outside of the US but there is an old commercial for Lay's potato chips (crisps) that comes to mind...
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