In recent months I noticed a drop in open TV signal in my house. Are two antennas, a VHF (Log Periodic antenna VHF PQVT-3004 ProEletronic) and a UHF (Log Periodic UHF outdoor antenna PQ45-1300 ProEletronic). The sign of the two was mixed in a VHF + UHF signal mixer Proeletronic PQMB-2300 and then descends in a coaxial cable with mesh of RG06 95% by conduit. There he goes through a Clamper Multi Protection with outbreaks Electrical Counter. Then is shared with the Tab or TV and FM Combiner 75 Ohms Cabletronix FMTVS. The TV signal then goes to a VHF Line amplifier / UHF 30dB Bivolt-PQAL-3000 Proeletronic and hence is divided to each TV in the House.
When I started to notice the degradation, I did a test by connecting a TV directly to the cable that comes from the VHF + UHF signal mixer Proeletronic PQMB-2300, even before passing through the Clamper, but I haven't noticed improvement. There remained then move on the less accessible: antennas and Mixer.
I started so suspicious of the VHF + UHF signal mixer Proeletronic PQMB-2300, because I suspect that an electric shock passed him about a year ago, as already reported here on the blog. The antennae no elements that can burn, I know. But in mixers tend to be capacitors. Are just decoupling capacitors, but I suppose your absence can bring interferences.
It could also be just the antenna positioning, even though she's pretty tightly fought since it was installed. Maybe some broadcasters took a turn for the worse in the signal. Maybe digital channels newly implemented in neighboring towns are interfering. Maybe some new building has been placed on signal transmission line. Are many variables.
A first attempt to adjust the antenna position failed, so I decided to look for a new signal Jammer to do a test. The Proeletronic PQMB-2300 seems to have stepped out of line. The Proeletronic left on the site just a template that appears lower than, the Proeletronic PQMB-2300B. I got one foot out the door with him. At the specifications on the site Proeletronic reports the following features:
Frequency: 54~ 216 / 470~ 890 MHz
Insertion loss: < 3,5 dB (VHF) / <4,5 dB (UHF)
Isolation between ports: > 40 dB
Impedance: 75 Ohms
Connector: F-type female
Dimensions: 49×41,5×13,4 mm
Weight: 19 g
This loss of 3, 5dB VHF and 4, 5dB UHF seemed a lot. But, on the Specifications PDF the information is another:
Now? Believe in < 3,5DB and <4,5DB or in <1,6dB. It is worth noting that the PDF is written PQMB-2300A, that is a previous model, that also seems to have stepped out of line, Although apparently identical to PQMB-2300B. This whole mess of Proeletronic made me think better look for another brand.
Most mixers are designed for broadcasting tapes, or for cables without plug, what doesn't suit my antennas that already has the cable output with plug type F. In the local market or find anything that would fit me, but the Internet Finally I found the VHF UHF signal mixer Thevear 1020-F. In your specifications, It indicates a loss < 1DB for VHF and < 1,2DB for UHF, in other words, Anyway less loss than the Proeletronic PQMB-2300B whatever the correct specification.
Of course you can't trust blindly in manufacturers specifications, but I decided to give a chance to the VHF UHF signal mixer Thevear 1020-F. It is very small and has the entries of VHF and UHF sides. The Proeletronic PQMB-2300 It had the advantage to have the inputs and output on bottom, avoiding unnecessary bends with cables. But, the new Proeletronic PQMB-2300B also have inputs at the sides.
After installation of the VHF UHF signal mixer Thevear 1020-F, and further adjustment in the positioning of the antenna, the TV signal showed good improvement. But I can not say that Proeletronic PQMB-2300 I was defective. Apparently he is in good condition. It may be that the improvement has come from Thevear 1020-F, but it can also be the second set finally ended in the ideal position for the current antenna, which is different from the position where she has been since installed and also different from the position of the previous adjustment.
It is curious that, with Google Maps Help and compass (one of my first purchases in DX, in 2008), I found what would be the ideal antenna position, pointing directly to where the transmission towers. It was the position where it was when it was installed. But the fact is that, in practice, today the position that gives the best reception is about 20 or 30 degrees to the right than would be the hotline. Furthermore, despite all the transmitting antennas are in the same place, the position which maximizes the signal from one channel is not necessarily the same position that maximizes the signal of the other channel. For example, the Globo signal becomes maximum, the SBT is bad. To let the good SBT signal, We need to sacrifice a little globe sign. And there will. E isso sem falar nos canais analógicos (Record, RIT, Culture, Canção Nova, Network TV, e Esporte Interativo ainda não tem sinal digital por aqui) em que fica ainda mais difícil medir o sinal, já que é praticamente só no visual. O jeito é procurar por uma posição que deixa a soma dos sinais dos canais a maior possível, mesmo que essa não seja a melhor para cada canal individualmente. É praticamente um Equilíbrio de Nash no mundo das antenas. 😛
No final das contas os canais digitais estão todos pegando bem, e a maioria dos canais analógicos também está com uma imagem bem decente, exceto pela Record que sempre teve um sinal horrível. Furthermore, ainda estou pegando também o SBT digital de outra cidade, com programação diferente do local, What is good to get the Keys when the local affiliate resolves to put some crappy informercial site at the same time (Yes, I know I can get the SBT on Sky, but there is no HD. Yes, I also know that the Keys is not HD, stop bugging me! :P). There are also several analog channels from other cities (in both VHF and UHF) I can pair it with varying levels of noise. Can be useful to see that football game that's going on in the local stadium and can't be streamed here, but it's on the Globe of the nearby town. The opposite also applies, Sometimes you can get a different game tuning the station of the city where the network is going on, because there will be an alternate game being streamed by the local affiliate.
Check out some photos from the VHF signal mixer + Thevear UHF F-1020:
It's up to note that the VHF signal mixer + Thevear UHF F-1020 is exposed to the weather because on initial installation of this antenna has been used a booster, that proved to be useless, because only saturated the sign, Since the gain of the antennas is already quite high. As or booster need to stay as close as possible to the antenna, the cable of them ended up getting short. To change that would need to take the antennas, so just getting to the next when the Proeletronic PQMB-2300 was installed. Ideally the cables would be longer and the mixer would be on top of the slab, under the roof, more protected. But as Auto Merger insulating tape seems to have noticed, Since the mixer seems to be intact. The UHF antenna is also upside down, with the cable going out on top, which was also a failure on first installation which was only realized with the antenna already locked and can only be corrected when necessary remove it. Apparently there is no prejudice in this error signal. Finally: Yes, There's a bird landed on VHF antenna. They like very antennas.