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Here's where Warren parked his screenshots.
? ??/g/BITX20/album?id=65861

I'm looking at the screenshots for harmonics of the major bands of 80,40,20,15,10m
Ignoring purple CW traces as there's an easy fix for that, just looking at the blue SSB traces.
Ignoring the WARC bands, as I seldom use them and we have plenty on our plate already.

In all cases, the transmitter is adjusted for peak at the transmitted frequency is at +33dBm, or 2 Watts,
this adjustment might be made by varying the amplitude of a 1khz audio sine wave into the mike jack.
The horizontal green cursor line is set 43 dB below that, or at -10dBm.
Any harmonics or spurs that get above the green line are non-compliant.

These displays are being generous, crank up the audio amplitude for more power than 2 Watts
and the non-compliant emissions will likely be worse.

80m looks clean, I assume the peak at the far left edge is an artifact of the spectrum analyzer
At 40m the 3'rd and 5'th harmonics are slightly non-compliant by 1 to 3dB, some might say that's not just too troubling.
By 20m, the third harmonic non-compliant by about 5dB , out of complince,? more like 5dB
At 15m, there' some cruft I don't understand well below 21mhz, otherwise compliant
At 10m, same as 15m, looks compliant enough to me except the cruft at around 11.3mhz.

So what's the low freq cruft I see on 15m?? Just artifacts of the test setup, or real emissions?
Perhaps Allision has a point, and this will only be cleaned up by appropriate per-band BPF's at L1,2,3,4 of the uBitx.
There is a short blip at??(45mhz - FOp) = 24mhz, but it is fully compliant.
I'd guess it becomes non-compliant only when power is increased (by increasing the audio level into the mike) above 2W.
??
On 10m, the only non-compliant spur is a peak at about 11.3mhz, what's that?
There is also a just barely compliant spur at 16mhz, which is our expected? (45mhz - FOp) spur.?

I'm not familiar with spectrum analyzers, still a little bit hazy about VBW.
But from what little I know the RBW and VBW selections seem good enough.

The x axis is unfortunately not labeled in mhz.??
For those confused, consider the 10m screen shot here:??/g/BITX20/photo/65861/0
At the bottom it says span=80mhz, center=50mhz, and there are 10 horizontal divisions shown in the display.
So each division is 80mhz/10 = 8mhz, and the far left edge is 50mhz - 8mhz*5divisions = 10mhz
The non-compliant peak is about 1/6'th of a division to the right of the far left edge, so at 10mhz + 8mhz/6 = 11.3mhz
?
Jerry, KE7ER