Waited about 8.5 years to get these items fixed.
update ---green screen for me
blackhole-community.com
Vu+ Zero 4K: blindscan, symbol rates and radio in TNAP 7
The Zero 4K has had several fixes in TNAP 7. Here is what changed, and what this receiver still can’t do.
Problem 1:
Universal LNB Blindscan now works. Before these fixes, blindscan on the Zero 4K found few or no transponders using Universal type LNB. There were two separate problems.
1. High band was never really scanned. Universal LNBs switch to the high band (11.7–12.75 GHz) when the receiver sends a 22 kHz tone. The Zero 4K’s blindscan program resets the tuner chip before it scans.
On this receiver the chip itself generates that 22 kHz tone, so the reset switched the tone off and the program never turned it back on. Every “high band” pass actually scanned the low band again. The blindscan program is now patched to turn the tone back on (or keep it off for low band) before each pass.
2. The live signal graph got in the way. The blindscan program talks to the tuner chip directly, bypassing the normal driver. While it runs, the signal graph on the scan screen was asking the driver for signal readings several times a second. One of those requests made the driver query the tuner chip in the middle of the search, which broke it, and the scan came back empty. The graph now pauses its readings while the scan is running and resumes when it finishes.
Tuning below 1 MS/s and above 45 MS/s
The Zero 4K driver told the system this tuner only supports 1–45 MS/s, so anything outside that range was refused before it reached the tuner. Satfinder, zapping and channel scans could not tune a low-rate radio carrier, or a high-rate carrier above 45 MS/s.
The tuner chip is capable of more. The driver now accepts
100 kS/s to 60 MS/s, the same top rate Octagon and other receivers with this chip family use. Low-rate carriers now tune and scan normally. For example, a 360 kS/s radio transponder on 99.2W scanned and found all five of its services, and a 447 kS/s carrier on 101W locked with a strong signal.
Why the Zero 4K still won’t blindscan below 1 MS/s
The Zero 4K can
receive carriers below 1 MS/s once you enter the frequency and symbol rate yourself. What it can’t do is
find them during a blindscan. The search itself runs inside the tuner chip’s own firmware. We tested this thoroughly:
- The setting reaches the chip. The blindscan program was patched to accept low symbol rates, and the chip takes the lower limit (scans run longer, so it is searching more).
- The search still misses them. It found nothing below 1 MS/s, even when scanning only a 20 MHz window around a carrier the receiver locks at 16.4 dB.
- The firmware isn’t the difference. We compared it with the Octagon SF8008, whose Si2166D does find carriers below 1000 SR. The firmware and the search code are effectively the same.
- The tuner chip issue. The Zero 4K pairs its demodulator with a Rafael Micro RT710 tuner, while the SF8008 uses an RDA5815M. The RT710’s narrowest filter is roughly twice as wide, and that most likely hides narrow carriers during the search.
So low-rate carriers have to be entered by hand on the Zero 4K, or taken from a satellites.xml or channel list that already has them. Once entered, they may tune and play, depending on LNB and dish antenna system.
Problem 2:
Radio channels that were silent
Some radio channels played and others were silent, while the same channels played on other receivers. The silent ones carry audio without the timing stamps (PTS) the Vu+ driver insists on before it plays a single sound. They usually also lack the clock reference (PCR) that normally goes with them. Most receivers just play such audio as it arrives. The Vu+ driver waited for timing information that never came.
The driver is now patched to play audio as it arrives, and those radio channels play. Channel changes between radio and TV stay stable.
Other improvements
- Chip names shown: Information → Receiver now lists the demodulator and tuner chip behind each tuner. On the Zero 4K that’s a Silicon Labs Si2166 with a Rafael Micro RT710. The same names appear in the blindscan setup screen and in saved blindscan files, so anyone can look up the hardware.
- Blindscan files record the hardware: each saved scan file notes which chips produced it, which makes results from different receivers easier to compare.
