I mean, sure, but you could also put some filtering on a couple of si5351 outputs to get them to be sine waves, then mix them to get higher frequencies with the kind of control (and yeah, a bandpass filter afterwards.) I've been thinking about doing that for a few rig restorations; it seems a common thing people are doing now to replace old unobtainium VFOs..
On Sun, 3 Mar 2019 at 16:58, Dexter N Muir <dexy@...> wrote:
I glimpsed an article a while back that said the SI5351 could be driven well beyond HF. If that could be 120MHz, let's fantasize: 120MHz is within the capabilities of an up/down counter. Let's say 0-1-2-3-2-1-0... Now use those logic levels to drive resistive dividers to a common output: Pseudo-sine! (somewhere between square and triangle, with a bit of filtering, more effective approaching 30MHz: the step-frequency is 120MHz, easily filtered out). Different counts could serve different bands or ranges, with the 120 clock varying as required to give finer frequency control. Add the present filtering and you're closer to Sine drive to the finals :) What say? 73 Dex, ZL2DEX
