can someone make for me a 834 mHz short range receiver?

Discussion in 'The Projects Forum' started by Colin Bailey, Mar 26, 2015.

  1. Colin Bailey

    Thread Starter New Member

    Mar 26, 2015
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    I have a Sennheiser cordless headphone transmitter, a couple of half decent speakers and an amp. What I want is a receiver so I can have the speakers at the other end of the room without any cables. I don´t want a Sonos rig and I can´t use the speakers with a Bluetooth unless of course there´s a B´tooth receiver and I haven´t found one . Any ideas anyone?
     
  2. blocco a spirale

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    Jun 18, 2008
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    You want a custom designed and built receiver/decoder to work with your Sennheiser headphone transmitter?
     
  3. tracecom

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    Apr 16, 2010
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    Have you googled bluetooth receiver?
     
  4. WBahn

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    Why do you want to operate at less than 1 Hz?
     
  5. Papabravo

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    843 millihertz is not RF, it's just nervous DC! (rimshot)
     
    Last edited: Mar 28, 2015
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  6. KJ6EAD

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    Apr 30, 2011
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    I have two bluetooth receivers. They're small, about the size of a large book of matches, and each cost about $30. You can pick them up at big box electronic stores, truck stops and the usual internet sources.
     
  7. Colin Bailey

    Thread Starter New Member

    Mar 26, 2015
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    thanks for respenses.........
    Blocco a Spirale................Yes I do unless I´ve missed something and there´s an easier or cheaper way.
    I don´t want a Bluetooth rx as I already have the Sennheiser one
    Also I don´t want small speakers as the point is I already have a pair of Kefs which work perfectly, have no resale value and woud be wasted if binned.
    I don´t know what hurts about Herz - Umm OK I´ve just looked at the thingy and it says 863-865MHz, presume a small m is millie and a big m is a Super Mac ?
     
  8. Papabravo

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    Here's the problem. Designing and building RF modules in that frequency range is an expensive proposition. The test equipment alone would cost a large car or a small house. Next a breadboard might be difficult to fabricate and keep running. Doing a PCB might involve multiple iterations. In short how fat is your wallet, how much time do you have, and how much is this worth to you?
     
  9. blueroomelectronics

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    Jul 22, 2007
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    It's going to be custom hardware in that Sennheiser, no chance you can DIY one without schematics and documentation from Sennheiser and even then it's not something they're likely to put in the public domain.

    Even if you did have all that it would require some serious electronics skills, layout skill, nunchuck skills...

    Cheaper just to buy a Sonos.
     
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  10. Papabravo

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    nunchuck skills!!?? I know I'm deficient in that area.

    Welcome back Bill.
     
  11. blueroomelectronics

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    :rolleyes: What no nunchuck skills... (
    It's been awhile, but the forums never seem to change.
     
  12. blocco a spirale

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    Jun 18, 2008
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    The obvious answer is to use a Sennheiser receiver; is this built into a pair of headphones or is it a separate box?

    To design and build one from zero is not really a practical option.
     
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  13. Papabravo

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    Nope...not a single nunchuck skill....heavy sigh
     
  14. Colin Bailey

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    Mar 26, 2015
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    I don´t understand any of this so I´ll say goodbye.
     
  15. WBahn

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    The thing to understand is that designing a custom radio-frequency receiver is a pretty major undertaking, particularly if it is to work with the signal from an undocumented transmitter (and by "documented", that would mean detailed documentation of the modulation scheme, the symbol encoding scheme, the media-access control scheme, the data packaging protocol, the data encoding scheme, and on and on). You could expect to spend $10,000 to $100,000 for such a design. Now, if you are going to make a million units, then you can spread that cost out at something between one cent and ten cents per unit. But if you only want one of them, then that unit is going to be prohibitively expensive.
     
  16. Papabravo

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    Nunchuks, or "danger sticks", are weapons used in martial arts. I have no skill with them and would probably hurt myself if I tried to pretend that I did have any skill with them.

    http://en.wikipedia.org/wiki/Nunchaku
     
  17. alfacliff

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    one way would be to use a uhf tuner from a tv with a scanner connected to the if output.
     
  18. Papabravo

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    Didn't they chop off the upper end of the UHF band for cellphone use prior to the digital changeover in 2009?

    I checked, and it is channel 74, so you'd need a pretty old TV to make it work.

    From the wiki:
    http://en.wikipedia.org/wiki/North_American_television_frequencies
     
    Last edited: Mar 29, 2015
  19. alfacliff

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    my tv's go to the top of uhf and some beyond. a tv made for cable tv should go that high. I have a uhf tv tuner in my home made spectrum analyzer that goes up to over 1000 mhz. got it from radio shack years ago. there are tv tuners available of all kinds.
     
  20. Papabravo

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    Yes, but you may very well find that anything built in the last 35 years may not cover the specific frequency of 830-836 MHz.. The cellphone companies have been very successful in preventing the construction of receivers for their spectrum.
     
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