So, I was setting up a TV server for someone in Germany using a Raspberry Pi and TV HAT, and for some reason all the ZDF channels were missing.
You see, there are multiple frequencies available for TV channels, and each frequency actually bundles multiple channels, in “Bouquets” (literally means bunch). And it seems “ZDF, 3sat, KiKa/ZDFneo, ZDFinfo” are always bundled together. Those were the channels I would not receive, even though they’re on multiple frequencies (redundancy perhaps?).
However, those multiple bunches go from 474 MHz to 570 MHz. For some reason, I did not receive any of them. The higher frequencies, with other channels bunched up, worked fine, however.
So, the antenna actually went into a splitter, one part then went into the Raspberry Pi TV HAT, and the other into the TV…
…the TV would receive ZDF and all the other channels just fine. So, it couldn’t have been the antenna or its position…
So, my next thought was the splitter. So, I removed it and plugged the antenna into the Raspberry Pi TV HAT directly, making sure not to move the antenna’s good, known-to-work position.
Well, that made a very slight difference, in that it went up from finding 55 “services” to 60… But no new channels, meaning ZDF and all those were still missing.
The TV HAT
So, my next thought was this: If the removal of the splitter made a very slight difference, but still no luck even though the TV could receive all the channels, maybe the TV HAT can’t handle weak signals, and maybe the signal from the antenna was simply weak, and maybe the TV had simply a more sensitive receiver built-in.
The Antenna Again
So, I ended up trying an “active” antenna, which is powered and has an LTE and other noise filters built-in, but most importantly, a signal booster. It worked!
My theory is that the Raspberry Pi TV HAT is maybe just not that good and needs a strong signal to detect anything, whereas other devices had no issues.
So, if you’re in the same position of not finding all channels, even though your TV can find them, then maybe try an active antenna with noise filter and signal booster (amplifier).
This is the one that worked for me: Amazon Germany Affiliate Link