Strange TV Behavior: No TVP1, TVP2 Signal on DVB-T Receiver - Roof Antenna, 15m Cable Issues?

Hello everyone. I have been struggling with my problem for quite a long time, over half a year, I think. Namely, I have a TV with a built-in DVB-T receiver. 15m cable and antenna on the roof, the so-called mesh. The problem is with the reception of TVP1 and TVP2, the rest of the channels work perfectly. It is mysterious that on TVP 1 and TVP2 there is a black screen for 3 seconds and the information "no signal", then the image is 5 seconds and again a black screen with the information "no signal", then normal image again and so constantly. It makes it impossible to watch TV. The best part is that the signal strength and quality on TVP1 and TVP2 are 10/10. Any suggestions? Could it be the fault of the built-in DVB-T receiver? Greetings.

czesteros1986 wrote:

Any suggestions?

Signal distorted. Remove the amplifier and insert a balun in its place. Ev. antenna replacement.

olekt2002 wrote:

czesteros1986 wrote:

Any suggestions?

Signal distorted. Remove the amplifier and insert a balun in its place. Ev. antenna replacement.

I forgot to add that I have been using a balun for about a year, a friend recommended and installed it.

Antenna with amplifier or balun? How is the situation on other HD channels?

Vytautas_YT wrote:

Antenna with amplifier or balun? How is the situation on other HD channels?

The balun for about a year.

The same thing happens on TVP info HD. But less often. A mux 3 nationwide.

MUX-8, a colleague is picking up or not?

Mux8 absolutely. And no problem, zero jam, etc.

Is it OK on TVP Sport HD?

Where is this installation located in Poznań?

sylvi91 wrote:

What kind of TV model would you say to get an idea of the dvb-t tuner parameters?

Built-in dvbt receiver, model; Panasonic txp42x10y

Added after 2 [minutes]:

TELMOR_PL wrote:

Where is this installation located in Poznań?

It is exactly 25 km north of Poznań.

Probably for MUX-3 (TVP) there is a colleague within the range of two transmitters - Śrem and lighting Poznań / Piątkowo both on the same channel 27. There may be a problem with the synchronization of both transmitters - one of the signals arrives with a delay and the head switches.

TELMOR_PL wrote:

Probably for MUX-3 (TVP) there is a colleague within the range of two transmitters - Śrem and lighting Poznań / Piątkowo both on the same channel 27. There may be a problem with the synchronization of both transmitters - one of the signals arrives with a delay and the head switches.

There is no such problem with the neighbors. For example, on TVP the story is ok. Assuming that there is a problem with timing, any advice to solve it? Does the fact that I have a symmetrizator matter?

sylvi91 wrote:

I do not exclude what TELMOR_PL says, but ....

czesteros1986 wrote:

Built-in dvbt receiver, model; Panasonic txp42x10y

Try to update the firmware of this TV, if any new ones are available.

I checked this eventuality in the tv options and the info appears that this is the latest version.
I connected a second TV to this antenna installation, much newer because it is 2 years old. For 15 minutes, Tvp1 never got stuck ?


EDIT. Hmm, I think you need to rule out the option that it's because of HD. Now I look like this and also TVP culture and TVP ordinary sport without HD, it also has such a case, but less often. On TVP 1 and TVP2 it is crazy to get this frequency. Hmm, but why didn't it happen on the second newer tv ?

Assuming that there is a problem with timing, is there any advice, solution?

The fact that she perceives better at the neighbour's house does not mean anything. Each case is different and requires an individual approach. The neighbor has a different installation - antenna, cables, location, ... and a different receiver.
The sensitivity of the heads in the receivers varies greatly.

sylvi91 wrote:

czesteros1986 wrote:

I checked this eventuality in the tv options and the info appears that this is the latest version.
I connected a second TV to this antenna installation, much newer because it is 2 years old. For 15 minutes, Tvp1 never got stuck ? ...
Hmm, the HD option must be ruled out. Now I look like this and also TVP culture and TVP ordinary sport without HD, it also has such a case, but less often. On TVP 1 and TVP2, it's crazy to get this frequency. Hmm, but why didn't it happen on the second newer tv ?

A newer TV can better decode the signal. Maybe you have a damaged dvb-t tuner in that old one?
But for me, the message "no signal" means no AV signal, not no terrestrial TV signal.

I guess it remains for you to buy some external dvb-t tuner

Now I am more inclined to the fact that it is not the fault of the tuner, but the synchronization of these transmitters. Because I also noticed these clips on TVP Kultury and TVP sport, not the usual HD ones. If so, then what advice, solution?

The reticle is a wide-angle antenna with a large "field of view", it has a large half power angle. If a location can collect signals from several transmitters at different angles, it will pick up signals from all of them. In this case, the only advice is to replace the antenna with a highly directional (low half-power angle) and direct it precisely at the transmitter from which you want to receive. Since it is lighting on the same channel, the use of a channel filter is not necessary. Choosing a different transmitter as well.

sylvi91 wrote:

czesteros1986 wrote:

Now I am more inclined to the fact that it is not the fault of the tuner, but the synchronization of these transmitters. Because I also noticed these clips on TVP Kultury and TVP sport, not the usual HD ones. If so, then what advice, solution?

But you've noticed that on the new TV connected to this installation, everything was flickering as it should be, so I don't understand your conclusions.
Are you sure that everything works on another TV? Take it easy for a little longer and you will see where the problem lies. Or are you writing now about jamming on this new hardware?
As it seems to me, the message "no signal" may refer to the audio-video signal, not the signal received by the dvb-t tuner.
As you said yourself on the tuner, strength and quality 10/10.
Maybe the tuner itself has a problem with decoding the signal from MUX, or there is a problem somewhere on the way to the screen with the AV codecs and / or the performance of the hardware / processor that processes it.

I apologize when I wrote something incomprehensible ? Everything is flashing on the new TV connected to the same installation, every channel, I tested for 15 minutes. The clips that I noticed also on TVP sport TVP Kultura refer to the old TV, this Panasonic. So you can say that MUX-3 is "limp", so there may be a problem with this synchronization, and this old TV and the built-in dvbt decoder do not grasp it, so I will probably look for a new dvbt tuner.

czesteros1986 wrote:

signal strength and quality on Tvp1 and Tvp2 is 10/10

Are these parameters for k.27?

czesteros1986 wrote:

Panasonic txp42x10y

It's kind of weird. Panasonic TVs have probably one of the best dvb-t tuners. I have an 8-year-old plasma from the X20 series myself and tested it on various signals. Most often with a positive result. Panasonic received steadily when external decoders had hiccups on the same signal. My antenna also receives one channel in SFN from three transmitters (10 km / 30 km / 45 km). And on it I have the worst quality (according to the meter), but Panasonic shows stable 10/10. The real testing ground was the period of dvb-t implementation and the successive incorporation of new transmitters in SFN. A few years ago, when the synchronization broke down, even for a few days on the SFN channel I had the maximum signal strength and quality - 0. When Emitel synchronized the transmitters, the signal suddenly returned to 10/10. Fortunately, this situation has not happened again for several years.
My Panasonic is also quite resistant to signal clipping. The reception fading appears only around 105 dBuV (according to the standard it is max. 74 dBuV).
A meter with echo measurement is needed to diagnose the problem.

I checked almost all channels, 99% of those terribly persistent glitches I mentioned earlier Tvp1 Tvp2, Tvp info, Tvp culture are on channel 27. Any conclusion? And these parameters 10/10 are for k27

I think the conclusion has already been made a few posts before. "Something" is happening on channel 27 - I bet on synchronization, or rather the lack of it.

So what is the best solution? Buy a new external DVBT tuner (considering that everything worked beautifully on a new TV with this installation), or buy a new directional antenna? But will it catch all MUXs from my location with such an antenna? Best regards and thanks to everyone for your help.

czesteros1986 wrote:

25 km north of Poznań

With the antenna aimed at Śrem, almost on the same azimuth, you have strong mux-3 illumination (27/20 kW) in Piątkowo in Poznań. So two transmitters transmitting the same at a distance of about 20 and 60 km. The suspicion of a lack of synchronization seems to be justified, but ...

czesteros1986 wrote:

It is puzzling that it shows up on tvp 1 and tvp2 black screen for 3 seconds and information "no signal" then there is a picture of 5 seconds and again a black screen with the information "no signal" then normal picture again and so on over and over. It makes it impossible to watch TV. The best part is that the signal strength and the quality on Tvp1 and Tvp2 is 10/10

Since the no signal message appears, there should be some reaction on the signal bars. Do you have a stable 10/10 all the time?
What can you try to do in this situation?
First, change the direction of the antenna, the height of its suspension or the place of its installation. When these procedures do not bring a positive result, you can think about the next steps with replacing the antenna or buying a receiver - necessarily with DVB-T2 / HEVC .

Before buying anything, I would measure with a suitable DVB-T meter and check the spectrum and spectrum on channel 27 using the current antenna. The measurement should identify disturbances and the result should help you make a purchase decision.

_kli_ wrote:

Since the no signal message appears, there should be some reaction on the signal bars. Do you have a stable 10/10 all the time?

I just checked. On those channels where the problem in question occurs, no signal, strength; 10 on the other hand, the quality suddenly drops to 0 and suddenly rises again to 10 ?
Generally, thanks, gentlemen, for your help so far.

Added after 2 [hours] 17 [minutes]:

I was on the roof a moment ago, I connected the cable to another old type antenna (as shown in the picture) great reception, but the problem did not disappear on the MUX-3, the same no signal, black image every 5 seconds.