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borjam

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Everything posted by borjam

  1. Looks like that, I've seen similar on other forums. Probably other posts will contain links to advertisements.
  2. I agree. And it's a shame that many companies are relying on Facebook for customer communication instead of setting their own systems. Of course it's cheaper. It reminds me a bit of the situation with the Flash plugin. I always refused to install it because of critical security and privacy issues and sometimes visiting the websites of pro audio manufacturers without it was a real nightmare. Of course Facebook is worse, their behavior seems to be outright criminal.
  3. Late, but for the record I connected my MixPre-3 to a laboratory power supply measuring consumption depending on the operating options. I found out that Bluetooth is essentially free. After all it's very low bandwidth status updates for the meters and time code, it does not send audio after all. The worst offender is the gorgeous screen that, at the same time, you can see under bright sunlight.
  4. True, but I was thinking about the non linear effects, ie, receiver saturation. In a link with enough interference to cause intermodulation on the receiver the directional antenna may be more beneficial on the receiver, as it will attenuate off axis interference (unless Mr. Murphy makes the powerful interference exactly on axis) And in this particular application there is more bandwith from the "transmitter" to the "receiver" (audio) than the reverse (feedback/control signals from the "receiver" to the "transmitter"). Just from a theoretical point of view As for the 941 MHz band, can you use it for wireless microphones in Europe? I have checked quickly at the current Spanish regulations (and it's more or less the same in all the EU) and except for low power wireless telephones I don't see other applications, but I have just checked on the latest update, more on this later). At least the Spanish regulation mentions the 863 - 865 MHz band for wireless microphones, but preferably non professional applications.
  5. I think some improvement can be expected. For starters, the transmissions won't be symmetrical with more bandwidth being used for audio from the transmitter to the "receiver" compared to the feedback signal sent from the "receiver" back to the transmitter. So, a properly aimed directional antenna would at least help reduce interference on the most critical point. Unless, of course, the worst offender is aligned with the RX and the TX. In that case, miracles don't exist
  6. The 2.4 GHz spectrum is a mess. I would bet for a properly regulated cognitive radio approach on the traditional UHF bands or even TV channels exploiting the fact that the whole band is not busy everywhere. As for the 2.4 GHz antenna, remember that it can be challenging to build a good one. Tolerances are tight and it must have quite a usable bandwidth.
  7. In Germany talk to WiMo. They have a good assortment of antennas and they sell both to hams and professional users. As you can't install an amplifier close to the antenna (the "receiver" in digital systems such as Deity is actually a transceiver) keep the cable as short as possible. Another advantage of Wimo is that they can build a pigtail to your specification and they have a good selection of low loss coax cables. Also bear in mind that a splitter will add losses by itself.
  8. Maybe they have been placing those mystery monolithes around the world
  9. I’ve actually seen something similar working. A friend built a prototype using ultrasonic transducers and beaming an amplitude modulated 40 KHz beam. He considered a product for museums in which statues would “speak”. I thought it offered endless opportunities for pranks. It was rather creepy to hear a voice speaking just behind you, really close, only to turn around and see nobody!
  10. AMD has begun to be a serious threat now, if only. It's funny because the Intel 64 bit instruction set was actually designed by AMD, Intel's option, Itanium (a satirical IT website from the UK called it Itanic) fell into oblivion. So, benchmarks are out and the new ARM processor surpasses even the fastest Intel based laptops Apple is selling. Interesting times, this will be like the Unix workstation wars with cutthroat competition among DEC, Sun, IBM, HP...
  11. It should be trivial to recompile (just tick a box so that it generates a fat binary with Intel and ARM code) if your software is somewhat modern. But I guess Pro Tools has a lot of legacy code written for vacuum tube based processors The same can happen to other pro audio applications such as Digital Performer, etc. First benchmarks are out and the results are indeed impressive. https://www.macrumors.com/2020/11/11/m1-macbook-air-first-benchmark/ My only disappointment and the reason why I think I will still wait for a year is, the Macbook Pro has just two USB-C/TB ports. As for fat binaries, I own a NeXT cube and I remember that back in the day NeXT binaries had four versions bundled: Motorola 68000, Sun SPARC, HP PA/RISC and Intel x86. And after all, Macos X is "NeXTStep NG NT ++++++"
  12. My apologies in that case! Maybe I tend to overreact to the antenophobia nonsense because it irks me so much.
  13. Actually, Quantum Physics shows a somewhat non intuitive property. If a radiation source doesn't have energetic enough photons to cause a non thermal effect, ie, it is non ionizing, no matter how many photons you receive no ionization will happen. Only thermal effects. Remember that the number of photons is the intensity of the radiation. Now, imagine you are in Normandie and you want to throw stones at England. No matter how many stones you throw, none of them will hit the target. This is important because there is no cumulative effect for non ionizing radiation. Using your Wifi, mobile phone and wireless microphones 24x7 does not increase a non existant risk because those photons simply will not break chemical bonds. Of course, if the radiation is very strong you can get a burn, but the low powers of typical applications make it simply impossible. So, it's not that it's negligible. It simply is not. Unless, of course, deletereous effects are proven. I forgot to mention that the Ramazzini study (which was pretty well made I think) failed to show a dose dependent response. That also reinforces the idea that the observed effects were actually statistical artifacts.
  14. Yes but antennas can have quite a high voltage. I have a HF antenna in my balcony. It is a loop antenna with a capacitor rated for 5000 V. And yes, depending on the transmission power voltage across the antenna can reach that value. So, no touch when using it. As I live alone it's not a problem. And yet the most likely cause for their cancers, if it was related to radars even, was the X ray emitted by the vacuum tubes and not the microwaves. Exactly. Not even an order of magnitude higher powers should be a problem. There are lots of kinds of radiation So, I would say. Ionizing radiation (ultraviolet, X or gamma rays or nuclear radiation) is of course dangerous. Visible light, unless you are using a laser, is not dangerous. Infrared? Well, it depends on power. If you don't sleep alone, your partner in bed will be radiating infrared. Of course the power is so low... According to Physics you shouldn't be afraid of the radio transmitters you use. Even walkie talkies with 5 W if you ever use them. Now, if on April 1st Lectrosonics announced a gamma ray based wireless microphone, I would get scared!
  15. I just watched today's Apple's "mass". Pretty interesting, the new processors are really efficient as expected. And they have even lowered prices a bit. Not surprised, as Intel prices their processors as they want holding a virtual monopoly. Interesting times coming, especially with those so called "neural" units tailored for machine learning calculations.
  16. As far as I know, there is no hazard unless the power is really high. Let me elaborate: there are two possible effects of electromagnetic radiation: Thermal and non thermal. The non thermal effects (ionization) require a very high energy photon. The radiation capable of doing that is called ionizing radiation and the ionizing spectrum begins at the ultraviolet wavelengths. Anything below that is strictly thermal. The photons simply don't have enough energy to do things like knocking a single electron from an atom. I know there is a lot of bullshit (sorry about the word but it's true) on the matter. There are lots of fake/misunderstood studies. The best study I have seen, the Ramazzini Study, doesn't prove any harm beyond a couple of statistical artifacts. IF you take those statistical artifacts seriously, in one case it turns out mobile phone radiation would be beneficial, go figure. Now: If mobile phone radiation (or the puny low power microwaves in use nowadays) were dangerous, think that mobile phones are working on the same frequencies former used for television broadcasts which used enormous powers. Cities have been blasted with such high power transmissions for decades. Effects? None. Higher microwave frequencies. Have you ever visited a port? X Band radars transmit around 10 GHz. With power measured in kilowatts, and using pulses (some of the antenophobiac people claim that pulses make radio frequency energy more dangerous). Do people living around ports die en masse? No. Do sailors suffer an unexpected high occurence of cancer? Not that I know, apart from maybe skin cancer in fishermen due to excessive exposure to sun light. There are countless reasons to really doubt that radio frequency at the powers we use it (and even an order of magnitude more powerful) can cause any effect. And if it was dangerous, what about visible light with much more energetic photons? If someone really proved any non thermal effect it would mean a Nobel award in Physics. Because it would tear apart all we know about the interaction between light and matter. (I forgot, I mentioned radars and in another discussion someone wielded a study on cancer cases among radar operators without bothering to read it... True, there was a high incidence on radar operators due to improperly shielded valve electronics leaking X ray which of course is ionizing and very dangerous, but with no relationship to the microwaves transmitted by the antenna which anyway was far far away from the operator).
  17. Old, but. https://vimeo.com/20416868
  18. Not intending to be fastidious, but you don't need a directional bridge if you just want to measure the total loss through the splitter.
  19. So I got a Rodecaster for some podcasts and live panels for my association and I just returned it. At least then plugging headphones on the front jack (the small one) and setting a high gain on channel 1 (I was using a Sennheiser MD441 for testing) I had some unpleasant "helicopter" interference that went away when using a phantom powered condenser microphone on another channel, and there was some AC hum present whenever I touched the screen. That only affected channel 1, not the other three. The microphone is fine (I use it every week at the club) and the cable is good as well, the same star quad cable I used to "test" (It wasn't any kind of formal test) the Rode NTG8 RF immunity. Is that to be expected?
  20. I wouldn't recommend at all to mix different digital wireless systems on ISM (Industrial, Scientific, Medic) bands. Each one of them may implement completely different spectrum arbitration/management features. And if I recall well, the Deity protocol might be somewhat of a bully, at least nudging (ahem!) WiFi networks to steer clear.
  21. I know two sources that may design those filters. One of them is in Italy and the other one in Greece. The prices are from cheap to reasonable. The first one is a radio amateur in Greece who is selling some nice products. I am quite sure he would take custom orders and, besides, this area would be a promising market for him I think. While his products are more oriented to the diy amateur radio operator, I am sure he can supply finished products for end users. http://www.sv1afn.com The other one is in Italy. He is actually selling filters for professional applications. I have purchased a couple of filters from him and they certainly matched specifications. However, he is rather chaotic with delivery times and shipping. Otherwise the products I have tried are great. https://www.jghitechnology.com/gb/
  22. Anything Ethernet based is so flexible. You can even use fiber instead of twisted pair. It’s much thinner and depending on the type of transceivers and fiber you use it can run for several Km while twisted pair is limited to 100 m.
  23. The main difference between the two antenna types is bandwidth. Log-periodic antennas are useful over a much wider range of frequencies. That’s the reason, I imagine, why the so called shark fin antennas are so popular for radio mics.
  24. I would say he is in Spain, gathering swift sounds for a sound background. (Several Spanish productions feature really conspicuous swift sounds, which is actually a nice detail because they are really loud in Spring and Summer)
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