Shop OBEX P1 Docs P2 Docs Learn Events
Amplifing A Wireless Camera — Parallax Forums

Amplifing A Wireless Camera

DiablodeMorteDiablodeMorte Posts: 238
edited 2005-12-06 23:18 in General Discussion
Hello,
I have the Swann Micro Camera. I am trying to boost its range. So far I applied the Hawking [noparse][[/noparse]HSB2] Hi-Gain WiFi Signal Booster and the Hawking [noparse][[/noparse]HAI6SIP] Hi-Gain 6dBi Omni-Directional Wireless Antenna to the reciever, and I have noticed a significant increase in range but I now feel my range problem may lie in the transmition power. How would I go about boosting the power of the Tx on the camera, It has one wire.(No two wire output)

Ideas?

Thanks in advnace,
DiablodeMorte

Comments

  • Robert KubichekRobert Kubichek Posts: 343
    edited 2005-12-05 03:00
    DiablodeMorte said...
    Hello,
    I have the Swann Micro Camera. I am trying to boost its range. So far I applied the Hawking [noparse][[/noparse]HSB2] Hi-Gain WiFi Signal Booster and the Hawking [noparse][[/noparse]HAI6SIP] Hi-Gain 6dBi Omni-Directional Wireless Antenna to the reciever, and I have noticed a significant increase in range but I now feel my range problem may lie in the transmition power. How would I go about boosting the power of the Tx on the camera, It has one wire.(No two wire output)

    Ideas?

    Thanks in advnace,
    DiablodeMorte


    One way is to use a camera with a higher power output, or use a camera that you can add a booster amp to....
    That means a camera with a coax output.... Also there are higher power output cameras that are frequency selectable,
    and have a matching reciever.....

    The best way is to use a camera with a booster amp connected to a good omni antenna, for max range transmitting.
    On the recieving end use a high gain directional antenna connected with low loss coax to reciever and pointed at camera....

    Basically what you have, is what amateur radio operaters call an ATV setup....


    Bob N9LVU scool.gif

    Post Edited (Robert Kubichek) : 12/5/2005 3:08:00 AM GMT
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2005-12-05 13:25
    If you·look up·"Pringle's can antenna" (assuming this is a 2.4G situation) you'll find sites where there are plans for making those sorts of directional antennas and there are plans for·making cut & paste sorts of·reflectors to modify OMNIs with to make them directional [noparse][[/noparse]usually 12 dB.]
  • steve_bsteve_b Posts: 1,563
    edited 2005-12-05 13:48
    Take care in selecting an amp for your camera.
    You'll want to be sure that your amp doesn't filter out your video signal. Some amps aren't geared for the wide bandwidth that video wants!
    So if you are getting some crappy video, this might be a reason! Test the video at the input to the amp and then again at the output...the only difference you should see is an amplitude change (obviously!)...there should be no deterioration of the video signal!

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    ·

    Steve

    "Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."
  • DiablodeMorteDiablodeMorte Posts: 238
    edited 2005-12-05 17:21
    Ok. So.. Would there be a problem with just jury-rigging the camera's antenta to the amplifier i already have even through there is no Ground output on the camera?
  • steve_bsteve_b Posts: 1,563
    edited 2005-12-05 17:38
    The little antenna does have a ground....but it's put to the ground on the circuit board rather than brought out to an actual wire.

    The problem with "jury-rigging" to an antenna to an amplifier is you are mismatching impedances....so...
    You're camera's transmitter section expects to see the 'antenna' as a certain load (or impedance)....and vice versa for the amplifer; it expects an input load of a certain amount (don't know what either really is)....

    So, if you ever bought a CB....they usually instruct you to buy one of those little SWR meters from radio-crack and 'trim' the antenna until you get the best reading. This is because, initially, the antenna isn't the right length for what the CB expects as a load...which means, they are mismatched.
    What happens in a mismatched configuration, is you get 'reflections' of your outgoing signal bouncing back into your transmitter. This sometimes doesn't mean a lot....but what ends up happening is, you get some of these reflections summing/differencing with the out going waves (think like ocean waves....you get rogue waves when two waves built on each other and you can get flat spots when they cancel each other out...). Short answer made long....but essentially you end up distorting your original signal.
    So jury-rigging, although a fun way to do many things, can also cause more issues if you are not aware of them.
    The reflections aren't so bad on low wattage things....but in the 100's of 1000's of watts you can burn up your transmitter pretty quick.

    I'm not sure how you were thinking of jury rigging the antenna....but if you leave the existing antenna in there, just remember that it's an antenna....it picks up on all sorts of RF in the air and can introduce more garbage on to your video signal, which your amp will 'hopefully' ignore, or will just amplify and send on down the line!

    I'd try the jury rigging....but just know that the picture may not improve!
    Sorry for the ramble...afternoon coffee break! [noparse]:D[/noparse]

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    ·

    Steve

    "Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."
  • DiablodeMorteDiablodeMorte Posts: 238
    edited 2005-12-05 20:29
    ohk. So.. Should I take the little thing apart to get at the onboard ground or just use the ground coming off the battery? Also, If I treat the outcoming antenna as a wire and just shorten it to the point where the chance of "bounce back" would be fairly low would that work?
  • Robert KubichekRobert Kubichek Posts: 343
    edited 2005-12-05 21:02
    DiablodeMorte said...
    ohk. So.. Should I take the little thing apart to get at the onboard ground or just use the ground coming off the battery? Also, If I treat the outcoming antenna as a wire and just shorten it to the point where the chance of "bounce back" would be fairly low would that work?

    NO, the impedance of a short wire antenna is calculated and designed into the "videocamera/transmitter" unit.
    At such a high frequency, correct design is critical!
    Use a camera with video out to a transmitter that has an antenna jack out "nominally 50 ohms"!
    That way you can use a higher power transmitter, that also has programable frequency out, and it is connected to a good omni antenna.
    With a matching reciever and a good highly directional antenna, you should get maximum distance "a few miles or more depending on output power of transmitter". If you add a booster amp, make sure it is compatable, for amplifying a video carrier at the frequency you are using.
    A WiFi amp is NOT suitable or designed to amplify a video signal.

    Bob N9LVU scool.gif
  • DiablodeMorteDiablodeMorte Posts: 238
    edited 2005-12-05 21:22
    Wait.. So.. What? Where could i get such a camera, and even through this may sound stupud: The Wifi Amp worked... So.. Why can't i use it?
  • Robert KubichekRobert Kubichek Posts: 343
    edited 2005-12-05 22:04
    DiablodeMorte said...
    Wait.. So.. What? Where could i get such a camera, and even through this may sound stupud: The Wifi Amp worked... So.. Why can't i use it?

    1) I have the Swann Micro Camera. I am trying to boost its range.
    It cannot be done to this camera, as it was designed with a wire antenna....You need a spy camera with a video out.

    2)So far I applied the Hawking [noparse][[/noparse]HSB2] Hi-Gain WiFi Signal Booster
    Which is designed to boost the output of a WiFi device (card or router) that in turn is connected to a good omni antenna.

    3) And the Hawking [noparse][[/noparse]HAI6SIP] Hi-Gain 6dBi Omni-Directional Wireless Antenna to the reciever
    Which is great but it is omni directional, a highly directional antenna has more gain, hence more distance, and will reject any interfearance from any direction other than from front of antenna.

    As you described your setup, you have the booster amp hooked up to the reciever, BUT it shouldn't be there, it should be on the output of the camera/transmitter, NOT reciever.. Also, the booster amp was designed for bi-directional comms.. A typical camera to reciever setup is one way only.
    By using an amp that was meant for WiFi, you could degrade your video quality, and distance of good reception will be less.

    Here are some links to better equipment;
    www.wirelessvideocameras.com/cgi-local/SoftCart.exe/online-store/scstore/mtek_minilinkhi.html?L+scstore+czgt1485ff2af02a+1133905224
    www.polarisusa.com/cgi-bin/product_listings.pl?listing_category_id=81
    www.dlink.com/products/?pid=342 Here is one that works over WiFi.

    You need to research more on whats out there, and how it works....

    Bob N9LVU scool.gif
  • DiablodeMorteDiablodeMorte Posts: 238
    edited 2005-12-05 22:20
    Ohk, thanks. Is there a reason the Wifi Amp did work though? From your post it seems that It shouldn't have helped
  • steve_bsteve_b Posts: 1,563
    edited 2005-12-05 22:47
    Well, it worked right....but did it work well!?

    Can you draw up a block diagram of how you have things?
    Is the amp on the output of your receiver??

    You might find some amps that will work over a broad range...and then there are others that have a more narrow filter that won't allow you such flexibility....perhaps you are getting some information out, but this may just be a fluke!

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    ·

    Steve

    "Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."
  • Robert KubichekRobert Kubichek Posts: 343
    edited 2005-12-05 22:49
    DiablodeMorte said...
    Ohk, thanks. Is there a reason the Wifi Amp did work though? From your post it seems that It shouldn't have helped

    It might of boosted the recieved signal, but Ii doub't it. It was probably the better gain from the omni antenna...
    Try it with out the amp, just hook the antenna to reciever. the results should be the same as with the amp in line....

    By the way, I have done both, using a WiFi with IP address, and the ATV way....

    Bob N9LVUscool.gif
  • DiablodeMorteDiablodeMorte Posts: 238
    edited 2005-12-05 22:57
    I'll do that.
Sign In or Register to comment.