Re: how to run in dongle in bypass or direct mode?


diyer
 

"You would want a good band reject filter with 30 dB or more loss
at 550 kHz through 1600 kHz that is hopefully sharp enough that
you have very little loss at 500 kHz and 1.8 MHz. Then as mentioned
above you'd ideally want a moderately good low pass filter at 55 MHz.
That should be good enough until some strong signals start appearing
near but above 55 MHz."

Are you concerned about this due to the potential of a powerful AM station nearby that could overload the input?

Fortunately, there was not a huge build out of AM stations in Central Texas unlike FM, so I'm not sure that this is that big an issue. Certainly worth considering.

I've already got a 5 ele cheby at ~45Mhz.

I do like the idea of using the same LO crystal osc to drive the dongle too. My 45/2 = 22.5 I assume close enough but I'm hesitant about unsoldering that thing on the dongle. Maybe I'll order a cheapie 820 version and not risk my E4000. To compensate for drift I've been leaving the thing powered up all the time and cking wwv periodically, so far good enough for WSPR.

73
wa5ngp

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