@statalite
A promised check of DVB-T/T2 tuners with updateDVB (kernel 5.4.54udl+) using the PC and USB sticks I currently have.
TBS6220 - CXD2820R demod.
No Spectrum button, hence no visible channels in chart, but checking a known transmitter frequency in the chart will tune to the respective channel (cursor will show frequencies).
Signal Strength and Quality bars show the respective values, but dB quality incorrect across the channels (too low -compare with PCTV 290e stick).
Blind Scan slow, ~5 mins to scan muxes available at my location (Sandy Heath transmitter).
PCTV Nanostick 290e CXD2820R demod.
Similar to TBS6220 no Spectrum button etc., but SQ dB strength shows what I consider the correct values across the channels.
Faster Blind Scan than the TBS 6220.
August T2110-v2 USB Stick (Geniatech T230 clone). Silicon Labs S12168-A20 demod.
Has Spectrum Scan and Blindscan buttons.
Spectrum Scan chart shows correct channels for my location. As usual, clicking on a frequency tunes to the channel, and brings up the Tuning screen.
Shows Signal Quality, but weirdly no Signal Strength.
Rapid Blind Scan - a few seconds for a complete area channel listing.
TBS 6522 Silicon Labs Si2183 demod.
Like the August, has Spectrum Scan and Quality buttons. Spectrum scan shows my Sandy Heath frequencies, but no results in Tuning clicking on a frequency (no perceivable SQ). The tuner doesn't appear to be picking up any signals Will look into this.
As expected, Blind Scan empty.
RTL-SDR USB sticks will also work with updateDVB, but DVB-T only.
Tuners with Silicon Labs chipsets seem to be the best (only?) ones for being able to have Spectrum scanning together with Blindscan.
Other updateDVB versions may perform differently with various tuners; just need to find another one to try.