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G6Tanuki · 16th May 2019, 8:27 pm

As a pragmatist, I really feel that this getting bogged-down in wrangling over noise-sidebands and phase-noise for what is really a pretty simple, low-powered radio to be used on the amateur-bands is horribly over-analysing the issue.

OK, if you were to be running 100Kw of carrier-power and you had another station 4KHz higher- or lower, noise-sidebands on your oscillator's fundamental _might_ be an iseue.

But, to be honest, if your on-channel radiated peak-power's only 10 or 20 Watts, and the wibbly sidebands of your oscillator are 30dB down, in these days of low-occupancy of the HF bands.....

**NOBODY'S GOING TO NOTICE**

**OR CARE**.

Build an oscillator!

Make it frequency-stable in the short-term [staying on-frequency for the duration of an 'over']

Put it on-air!

Stop worrying about seriously-marginal spectral-purity issues.

Go out and work the world!

16th May 2019, 8:27 pm	#37
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,005	Re: Franklin VFO ? As a pragmatist, I really feel that this getting bogged-down in wrangling over noise-sidebands and phase-noise for what is really a pretty simple, low-powered radio to be used on the amateur-bands is horribly over-analysing the issue. OK, if you were to be running 100Kw of carrier-power and you had another station 4KHz higher- or lower, noise-sidebands on your oscillator's fundamental _might_ be an iseue. But, to be honest, if your on-channel radiated peak-power's only 10 or 20 Watts, and the wibbly sidebands of your oscillator are 30dB down, in these days of low-occupancy of the HF bands..... NOBODY'S GOING TO NOTICE OR CARE. Build an oscillator! Make it frequency-stable in the short-term [staying on-frequency for the duration of an 'over'] Put it on-air! Stop worrying about seriously-marginal spectral-purity issues. Go out and work the world!