IR wired link

Discussion in 'The Projects Forum' started by xflyguy, Jul 22, 2010.

  1. xflyguy

    Thread Starter New Member

    Jul 20, 2010
    4
    0
    Greetings,

    I too am looking for some help with an IR remote application BUT with a difference. I have been using a very simple wired system to change music channels on my DirecTV receiver from my basement workshop. The receiver is located upstairs in my study.

    Basically, I have been using an IR phototransistor directly coupled to about 25’ of twisted pair. At the other end (upstairs) I have an IR LED connected across the twisted pair and positioned directly in front of the DirecTV receiver IR window. (I should mention that I use a DC wall wart, zener diode & limiting resistor at the basement end).

    This simple but crude setup has been working quite well for several years although due to the poor sensitivity I must position the remote accurately an inch in front of the IR phototransistor. This has become quite difficult now that a severe stroke has left me disabled and without the use of my right hand.

    I’d appreciate any suggestions for improving the sensitivity and acceptance angle of the “transmitter”. I already am going to try one of the receivers as suggested in the recent posting by jpanhalt. (Tx)

    Sorry for my wordy post; I’ll try to do better next time☺

    Len
     
  2. bertus

    Administrator

    Apr 5, 2008
    15,648
    2,347
  3. hgmjr

    Moderator

    Jan 28, 2005
    9,030
    214
    Can you provide a simple schematic of what your current circuit looks like?

    hgmjr
     
  4. Syniva

    New Member

    Jun 21, 2010
    25
    0
    I haven't done much with IR, but I've used those IR photo transistors before. I always found the signal to be rather poor, but it was so long ago, I probably just didn't know what I was doing.

    A few years ago I tried out a different IR receiver I salvaged out of a stereo system. It had three wires, two of which connected to 5 volts, and the third was an output. It was just amazing. I could point the remote in any direction, and a nice clean square wave came out of it.

    A friend recently told me that he bought one at Radio Shack which he was having a lot of fun with, which I guess was this:

    http://www.radioshack.com/product/index.jsp?productId=2049727

    I don't know enough to say whether or not the "38 kHz" part might be a problem or not. I'd assumed that the one I had was simply outputting the same signal that it was receiving via IR rather than functioning as an intelligent receiver. If that isn't what these things do then connecting its output to an LED might be pointless.

    Someone probably knows whether or not it would work.
     
  5. xflyguy

    Thread Starter New Member

    Jul 20, 2010
    4
    0
    Thanks for your response. I made up a sketch of my present setup but I am having difficulty sending it to you since there does not seem to be a way to attach the file to my e-mail back to you.
    The circuit is basically a 330 ohm resistor in series with a 4.7 volt zener diode both of which are connected across a 12 VDC power supply (one that plugs into the wall). The photo transistor is connected from the junction of the resistor and the zener and one side of the twisted-pair going upstairs to the IR LED which is returned back on the other side of the twisted pair to the negative side of the zener diode which is the negative side of the power supply. This Rube Goldberg system has been working for about seven years. But now because of my stroke and the inability to use my right hand, I need something with a little more sensitivity so that I don't have to precisely align the remote and the photo transistor in the basement to change channels. I hope this helps you to understand what my current system is like.
    Regards,
    xflyguy

     
  6. xflyguy

    Thread Starter New Member

    Jul 20, 2010
    4
    0
    Sorry! I blame it on my unfamiliarity with how the system works and in my lack of experience posting to of this type of forum. Can you give me a pointer to the general procedures (rather than the rules and regulations which I have already read?). How should I have gone about adding my original post? I'm not sure what you meant by my "hijacking" an existing topic.
    I already have had some responders and I think I have correctly been able to reply but I am still on the steep part of the learning curve. One of the responders wanted me to send him a sketch but I was unable to figure out how I could attach it to my return e-mail. Is there a way to do this? I'm sure I will learn the answers to these questions eventually and I look forward to becoming an active member of this forum.

    Thanks for your patience; I'll try to do better next time :)
    xflyguy
     
  7. xflyguy

    Thread Starter New Member

    Jul 20, 2010
    4
    0
    Thanks for responding. I have some IR "receivers" that I salvaged from some electronic devices and I plan to try them out on the bench. It may be the simple solution to my problem.
    xflyguy
     
  8. bertus

    Administrator

    Apr 5, 2008
    15,648
    2,347
    Hello,

    Here is the sction from the FAQ on posting images on the forum:

    Posting a schematic can be best done in .png format as that is sharper as .jpg.

    Bertus
     
    xflyguy likes this.
Loading...