On Sun, Mar 15, 2020 at 08:00 PM, hwalker wrote:
On Sat, Mar 14, 2020 at 09:38 PM, <hugen@...> wrote:
The NanoVNA-H4 uses DAC output dimming, so the brightness can be adjusted
using DAC commands. Dac_value = 800 is the minimum brightness, dac_value =
3300 is the maximum brightness, you can enter any number between 800-3300 for
brightness adjustment.
================================================================
Note: 1800 is the default, out-of-box, NanoVNA-H4 mid-range brightness
setting. I always wondered about the purpose of the "dac" console command,
although on the 2.8" NanoVNA-H's it's use is evidently reserved for other
(future?) purposes.
- Herb
The NanoVNA originally designed by edy555 allows the use of DAC to adjust VCTCXO, but when I made NanoVNA-H, I thought that adjusting VCTCXO was too much trouble for most users, so I used TCXO. For most VNA users, 2ppm TCXO can fully meet the test requirements. For geeks who may need more accurate frequency calibration, I think they can be easily calibrated by software. Therefore, the DAC on the 2.8-inch NanoVNA-H has no practical use.
