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Attention: RC-CAM.com will be closing down August 2021.

The RC-Cam.com forum was the very first online community dedicated to the advancement of wireless video cameras on radio controlled (R/C) models. This is now called "FPV" (First Person View). We are proud of the contributions that our members have made to the FPV hobby.

We've seen significant changes over the last twenty years. Initially there were a lot of eager R/C hobbyist that built their own video systems. Allowing these creative individuals to share their work was the purpose of this site. Now the FPV market is flooded with low cost systems; Sadly DiY FPV video projects are now rarely discussed.

RC-CAM.com (main site and forum) will be closing down August 2021. This is being announced now (March 2021) so that everyone has time to download any information that is important to them. After the site is shutdown the information will no longer be available here.

We appreciate every member's involvement with advancing the FPV hobby. It is indeed sad to say goodbye to all our online friends. Be safe and stay healthy.



Stevie

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Posts posted by Stevie

  1. The 4-array PCB patch does reasonably well. However, it is not completely suitable for wing mounting unless you fly mostly directly overhead. But, it's worth a try since it might be fine for what you have in mind.

    This particular PCB patch works best in receiver installations that don't need a huge amount of RF gain and can accommodate its beamwidth. It is especially useful in environments that can't use an omni on the Rx due to local interference sources, including multipathing. Otherwise, a omni dipole/ducky on the Rx does surprisingly well on 5.8Ghz A/V applications.

    FWIW, I think oxxyfx (the original poster) is familiar with Airwave patch antenna. I recall that he owns and operates the online store you linked to. :)

    Ok I now have 4 of these Airwave Phase array patches, these are not 4dbi as I previously stated, but are 7dbi :o

    #Specs from the factory data state:-

    Electronic Properties:

    Frequency Ranges: 5.8GHz

    Impedance: 50 Ohm nominal

    Gain: 7dBi(TYP.)

    Radiation: Patch

    (not stated.. Weight 10.6gms, with the short coax fitted)

    I tested a commercial 6dbi radome patch, the Airwave one blew it it out the water by miles. I also hooked up RSSI monitoring to check sig strength on the two patches, again the Airwave one came out top.

    In 'real' (ground) testing the airwave patch performed very well, with a wider reception angle than I thought possible, considering the gain of 7dbi. So this may work well on my FPV Heli, using the same patches on the ground station, with twin RX's & Oracle Diversity Controller.. etc.

    Steve

  2. For the omni just create a simple 1/4 wave dipole or use a re-scaled YB2normal Groundplane version. Dimensions will be very critical, so pay attention. :)

    I haven't seen DiY 5.8GHz PCB patch build instructions, but don't give up. No doubt someone, somewhere, has published such info. Otherwise, there are low cost PCB patches that are available commercially.

    Airwave make a PCB 5.8GHz patch, not shown on there website, but did see on another RF gear website advertising them for sale. It has 4 square copper area's etched, with what looks like tuned tracks coupling these together. I'll try and re-find it. Looks especially useful for wing mounting I imagine.

    ##EDIT found the link http://www.nghobbies.com/cart/index.php?ma...products_id=113 Just ordered a couple, I'll test and report back when they arrive.. Only problem, these are vertically polarised and only 4db gain.

    Steve

  3. I would suggest that paint, spray or otherwise, that is invisible to microwaves is not usually found in the paint department at Home Depot or Radio Shack......

    Now radomes and antennas can be painted and often are, but unless you're using TWT tubes or Magnetrons, I wouldn't recommend it either...

    It's one thing with a 50kw ERP radar set and quite another when speaking in miliwatts and DBs...

    I will say that it is customary to put on a light coat of lacquer (spray) to protect an antenna from corrosion on lower band ham antennas, but we usually stop treating them with anything at around 220 mhz.

    Easy way to find ot the paint/Laquer is absorbing microwaves.. spray some on a piece of paper, let dry then stick it in a microwave, if the paint feels hot when removed it's no good.

    I use Acrylic laquer, not seen any problems with power reduction.

    Steve

  4. I have purchased a few AMW630Tx/634RX modules and a wide variety of aerials (from no gain to 14dBi gain, both omni and patch).

    I will be spending some time in the local fields....

    Built many of this TX/RX combo. Managed 1km (10mW) with 2x 8db patches.

    Just built a 7 Channel 5.8GHz system pair, testing these now, line-of -sight is good, not so hot through buildings.

    Video quality is very good.

    Steve

  5. It look very good, do you have an idea of the price ?

    Sorry for late reply... much work and travelling.

    I can find out for you.. I know the 0.0015 lux version with no Case and outdoors weather housing and wall bracket is about £200. I use 2 of these here for security testing with my IR illumination design prototypes.

    The 0.00004 version is obviously much dearer, theres an extra digital processing PCB behind the cam PCB.. I'll find out the price, without the case? Your Heli maybe big enough to take the whole camera?

    I have played with this camera, with a 10 to 1 zoom F1 lens... it's a bit amazing, if theres one light anyware near, the image is very clear. These are used by Police etc. Should be good in moonlight. They are not messed up by 'smear' from moving headlights etc..

    The onboard processing is a bit advanced and does some clever stuff ;-)

    You can also use cheap IR Led markers on your landing zone, these would appear like flares to the camera ;-) Also you could use an IR spot on the Heli, using 810/880nm 5mm IR leds, these are not expensive. I use 2 strings of 6, off a variable regulator, 0 to 100mA per string from 12V, other combo's to suit your volts available power etc.

    #Note: Forget the pinhole cams, these are useless at IR, you need the lensed versions, obviously these collect much more light.

    hope this helps

    Stevie

  6. I'm gobsmacked :blink: You guys are unreal. Watched the video with amazement. The flight was very smooth, much cudos for a risky flight.

    The camera was performing quite well for only moonlight.

    If any of you are really serious about night flights? I have a link to some specialist Mil Grade low light camera's these go down to 0,00004 lux, rivaling gen 2 night-sights..

    Ultra low-light Cam

    If any of the more ambitious amongst you tried these cams, you would need the cam module only, as these come normally cased.

    I would love to see a setup like this ;)

    Stevie

  7. Slightly related to this sniffer question.. I made a sensor to hookup to my Tektronix scope.

    The sensor was made from a small ferrite bead (cylinder shape) this was cut down it's length so I ended up with a 'U' shape channel. I wound as many turns of thin enameled copper wire as I could get in. this was connected to a short run of coax and fed through an old plastic pen body, bonded with araldite, terminated with a BNC plug.

    When used with my scope it's very handy for sniffing out noise. my TDS3032 only goes upto 300MHz, but still fairly useful.

    Stevie

    post-13-1146829704_thumb.jpg

  8. Sure no problem.. Not sure why theres a problem with stereo? I'm assuming you would be using the TX/RX as a pair, not all 2.4GHz channels are not the same from different manufacturers ;-)

    Channel Freq's: 2414, 2432, 2450, 2468MHz

    Note: for an idea of scale.. the TX wire antenna is 31mm.

    The PCB for the TX is same size as module, all smd. Wiring was a quick latch-up just for testing

    The RX was made using a Conventional & Smd component mix, no problems of space for the RX.

    The small camera is a low-light B/W Russian job, (0.01 lux) nice size, unfortunately no longer produced :-(

    Steve

    post-5-1146735241_thumb.jpg

  9. I've seen a few of these 'supposed' higher sensitivity antennas's sold as higher gain 1/2 wave's when in fact they just longer plastic mouldings, with a 1/4 wave dipole.

    I've been messing with receiver dipole antenna's swopping the 1/4 wave for a 1/2 wave dipole makes heaps of difference to the receiver sensitivity. A recent simple walk test validated this: 1/4 wave gave about 80 metres.. 1/2 wave gave about 150 metres (TX was on my workbench in house, so not as good as line-of-sight)

    Try modding that small whip (probably 29mm) to 62mm (Ch 1) or 60.77mm (Ch 4) and retest.

    Stevie

  10. Hi all. I'm new here as of today. Although the only model I have is a leccy heli and not in the same league as what I'm seeing in here ;-)

    My reason for joining this forum was from parallel interest in 2.4GHz video.

    I design devices that use this band. I recently purchased a TX/RX combo that may well be of interest here.

    The TX size is 30.6mm x 28mm x 3.70mm so would appear to be good for flying.

    Power supply is 5V -AT-55mA nominal. 10mW standard output power.

    The matched RX is also small.

    It is possible to add the various external components directly to the TX module directly ( 2x caps video in & antenna out) this keeps weight down to the minimum.

    The picture quality is excellant.

    Heres a direct link to the products>> 2.4GHz AWM630TX/RX

    I hope this is of useful interest.

    Steve

    edit: Added TX PDF below

    AWM630TX_SPEC_Ver_A2.pdf

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