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  1. flippineck

    Why Use A Business Telephone System For Your Business?

    Lack of proper training for engineers & too-harsh targets for sales. I survived in the job simply because I was prepared to put in so many unpaid hours outside the 9 to 5, I just found it interesting. I found there was a real cameraderie amongst telecom engineers both onsite and online and that...
  2. flippineck

    Why Use A Business Telephone System For Your Business?

    I was a telephone engineer working for a "business communications specialist" for many years. I loved the job as a young man but I wouldn't have the energy now. I believe the benefits of a PBX are very often hugely oversold by the sales arm of these businesses! I very often came across the...
  3. flippineck

    Repurpose grid-tie technology for local scalability?

    I've got a little diesel generator?
  4. flippineck

    Repurpose grid-tie technology for local scalability?

    I've always found impedance a hard thing to understand. Could I build some kind of small device to make the impedance 'look' correct?
  5. flippineck

    Repurpose grid-tie technology for local scalability?

    Just linking in another thread for me to come back to https://www.electronicspoint.com/threads/diy-1kw-grid-tie.10664/page-2 One of the posters mentions an "anti-islanding circuit" in there, put there to prevent grid tie inverters zapping line repairmen. Wonder if I could use my Chinese jobby...
  6. flippineck

    Repurpose grid-tie technology for local scalability?

    Could I connect together the outputs of multiple seperate grid-tie power inverters to get more power? They'd all be fed off the same battery bank, charged by solar PV. For instance say I have 5 identical inverters each rated at 1kW continuous, 240V 50Hz, with grid-tie capability.. could I use...
  7. flippineck

    Mins from CR2032 @ 200mA?

    Thanks guys. It's actually for a cat. Found some info on the mobius - great thanks :) Kinda wondering now about a change of plan though, this cat goes missing for a week at a time & I want to find out where it's going. Me & the missus thought it was one particular neighbour down the road trying...
  8. flippineck

    Mins from CR2032 @ 200mA?

    For how many minutes could a CR2032 coin cell supply 200mA? What kind of miniature cell or battery is best at supplying this sort of current for the longest time? It's to run a 9V 200mA camera on a pet's collar, so the power supply must be as small and unobtrusive as possible. Maybe I could...
  9. flippineck

    Understanding the nature of the electric field

    OK I'm now happily just accepting that the EM wave travels no prob through free space, basically by magic. I'm hoping that to form a basic working understanding of antennas, that's all I need, and that I don't need the brain of Hawkins; just to accept that there is such magic and it does...
  10. flippineck

    Understanding the nature of the electric field

    So there isn't a constant 'zero value' field everywhere, like a 3d net, then? I thought that if you could think of it like that, then it would be logical to visualise that a 'twang' in one corner of the net could propagate out through the lattice to infinity, even though you didn't quite know...
  11. flippineck

    Understanding the nature of the electric field

    According to wikipedia these seem to pop into existence when maths makes them convenient, and disappear again when not needed by the maths.. seems like a modern day equivalent of "Here Be Dragons" on old maps! I guess I'm best forgetting the how and why and just accepting that things just are...
  12. flippineck

    Understanding the nature of the electric field

    Reading a discourse on the nature of the electric field, I keep running into discussions of discrete charges 'creating' an electric field in the space surrounding them. http://www.physicsclassroom.com/Class/estatics/u8l4a.cfm https://van.physics.illinois.edu/qa/listing.php?id=414 Is it such...
  13. flippineck

    Android cell info

    my bad terminology I think, I just meant carrier as in 'network company'. no bottom to the complexity of cellphone signals! I'll go google orthogonal frequency division multiplexing as far as I can tell, saying "3's LTE is on 1800MHz" is just marketing speak then really.. although all the...
  14. flippineck

    Android cell info

    Found an app that claims to give info on these things; Using my SIM in a smartphone the app gives: LTE on 1920-1980 MHz up & 2110 - 2170 MHz down TDSCDMA 1900-1920 & 2010-2025.. wikipedia says TDSCDMA is a Chinese thing, I'm in UK, what gives there? WCDMA 1922-1977 & 2112-2167 2G/GSM as...
  15. flippineck

    Source code from HEX code ?

    I don't know specific details regarding PIC but in general, converting hex code to source (use of a decompiler) is unreliable at best; all original comments etc in the source tend to be lost. Use of a disassembler may help if you are comfortable with reading and understanding the output assembly...
  16. flippineck

    Android cell info

    does anyone happen to know if you can get an android powered cellphone to divulge current carrier frequency information?
  17. flippineck

    Receiver Antenna Selection

    I've had the best experience with collinears. I've tried the type that involves 3/4 wave vertical sections joined together by circular 1/4 wave - long loops in the horizontal plane, with the highest vertical section being 10% less than 3/4 wave and the lowest vertical section being a half...
  18. flippineck

    Thinking of making my own electric pendulum

    Or better still use straight lengths of stiff copper wire as the sensor contacts - you could still tape or glue them to the inside of the toilet roll but they would be easier to attach flying leads to by soldering.. Or what about, use four small sheets of veroboard / stripboard, the type with...
  19. flippineck

    Thinking of making my own electric pendulum

    Instead of a cube of tiles why not use a toilet roll inner, and glue very thin strips of tinfoil inside to make almost like, an inverse commutator. I think painting with molten solder would be difficult also a cylinder would mean the pendulum would be equidistant from all sensor patches
  20. flippineck

    Looking for 1990 Kenwood A-54 amplifier parts

    Someone once suggested the trick of opening a pot up, and carefully scribbling on the resistance track with the softest of graphite pencils.. as a last resort after contact cleaner if that didn't do the job. Think I'll only try that just before chucking the unit in the skip. If it wasn't cause...
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