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About Thorn3

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    RC-Cam Visitor
  • Birthday 12/28/1963

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    Mechanical Engineering.
    Model aircraft.
  1. Go to Range Video and take a look at their 500mW video/audio transmitter. Mine easily transmits well over 2000 meters. The receiver should use a good patch antenna. Here is the link: http://rangevideo.com/
  2. Thorn3

    TX/RX Advice needed... 900/1300/2400

    I use a Range video 500mW Tx with their dual Rx. I chose 900MHz for good penetration and to prevent interference with other systems, be they RC or other. With a patch antenna, I get about five miles. If you are only looking for a bit over 1 mile range, then a 250mW would be fine. It is better to have more power than you need to take interference into account from the environment, trees, buildings etc. I get crystal clear transmission with no break-ups at all. I run the Tx at main pack voltage of a LiPo (11.1 volts). Reducing the voltage will decrease the range. Allow airflow over the Tx, as they do get rather warm.
  3. Thorn3

    3.3 voltage reg for Aw633

    I have not used the 633. I have only read its data sheet. I would assume that 3.5 volts would not damage it at all. If it is like most other modules. There is typically some flexibility. I know this is a DIY site. I only suggested the available RF transmitters, such as the Range Video Tx's, because RF can be complex if someone isn't well versed in it or feels uncomfortable building one. All video Tx's that I have used and read about, state that input voltage is a function of range. So, even my 500mW Tx will be greatly diminished in range, if I use a lower input voltage. Since I am not familiar with the actual use or architecture of the 633, it confuses me why 'that' module is different from all others, in its ability to transmit long range at only 3.3 volts, without the use of a broadband amplifier on its RF output stage. Unless it has a built in broadband amplifier, but then the data sheet would not claim a range of only 500' and say that it doesn't require a license to use, due to its low output. Video Tx's with an output of 250mW and above, require a license. Although, I have yet to meet anyone that actually has a license to use them. But, since the 633 is sold under the statement that it does not need a license to operate it, I lean towards believing that it really is a low power, short range Tx. If anyone has technical documentation to show otherwise, I would like to see it. This is not a challenge to anyone's success with the 633, simply technical curiosity. I believe heavily in a DIY environment. Most of what I do is DIY. But to me, an existing RF transmitter is a building block, just like any other block, such as a camera, battery, voltage regulator or IC's. Putting the whole system together, to me, is DIY, be they discrete components, or a combination of blocks and discrete components. This is because you still have to deal with power regulation, wiring, filtering etc. With the video Tx I suggested for your project, you would not need to regulate the voltage to it. You could power it straight off a 3 cell. The price is less as well. But, you would have to regulate power to your camera and devise filtering on the signal and power lines. It is still a DIY if you use an available Tx. Just another building block in your DIY system. If building a DIY Tx is your goal, then certainly go with the 633. If you find the range is not suitable, then simply add a broadband amplifier to the RF output stage and you will see a dramatic increase in range. I am familiar with the National Semiconductor LM3940 voltage regulator. I believe it would be good in your application, regarding the 633. (the LM3904 is a transistor : )) Even though the LM3940 claims it does not need a heat sink, I would use at least a small one anyway (I don't know the working environment), unless you are going to design a PCB and use a surface mount package, so you can solder it down to a copper plane for heat sinking. But, this will increase your PCB footprint. Always believe something will overheat as a general rule. Ambient temperature can have adverse affects on thermal transfer. You will be potentially using more than 50% of the total capacity of the LM3940. Typically, if something such as a voltage regulator overheats for any reason, it will go into thermal shut-down and you will lose your power.
  4. Thorn3

    3.3 voltage reg for Aw633

    Any pins showed to be wired external to the block diagram of the component, are grounded to a common ground plane, or trace, to the negative terminal of the supply. They are not internally grounded. Here is their text regarding channels: "Channel selection is four channel and default value is ch4 (not enable). Other channel can be selected by pulling low to enable". I understand this as meaning that channel 4 is default selected (enabled internally) and pulling any other channel pin to ground will select that channel. Switches such as PCB DIP switches would be nice, or jumpers so you can select any channel at any time, without having to solder or unsolder the pins to change channels. If you fly FPV with other pilots, the ability to change channels in the field is very important. 470uF is a pretty high value, at 16 and 25 volts, so I don't know if you can get them in ceramic or Tantalum. I don't want to insult anyone, but I am curious. Why are people using the 633? A circuit has to be built, it uses a specific, low voltage input, resulting in only about 500 feet of line of sight range -AT-500mW. Seems like an awful lot of trouble, when there are video/audio Tx's out there that are plug and play, use a range of input voltages from about 7-12 volts and have a range of several miles/kilometers and they cost less than the 633. Is it a license issue?
  5. Thorn3

    3.3 voltage reg for Aw633

    Certainly use a heat sink. I live in the desert, where it is hot much of the time. The difference between ambient air temperature and ESC's or video Tx's temperature, isn't much. Thermal transfer is more difficult as a result. In the picture, you can see a simple, GWS Texan foamie(1/12 scale, parkflier) outfitted with a pan and tilt camera and 500mW video Tx. You can see that my ESC is in the outer wall of the fuselage. The video Tx, is mounted behind the second seat, but also outside the fuselage. This is to allow the greatest amount of airflow over them. They are both heat-sunk of course. The camera gets fairly warm and the video tx gets quite hot. Due to this and the need for airflow to keep things cool, there is no glass in the canopy. It was built to replace the original vacuum formed canopy, but is a framework only (laminated Birch veneer). In my two 1/12 scale P-51 Mustangs (full balsa builds) I take advantage of the chin intake and the oil cooler intake (under wing scoop) to keep things cool. ESC at the chin intake and the video TX inside the oil cooler intake duct. Air is free to flow into the chin intake and the oil cooler intake. All air is free to flow through the fuselage and out the oil cooler exhaust hatch. Funny that ESC companies always say to locate the ESC in an active airflow for them to run properly, yet most people bury them in stagnant air inside the fuselage. In my case, here in the desert, I cannot get away with that. So heat sinks and airflow in any clever way that can be found. To avoid the need to purchase heat sinks, I typically use ones found in other devices. However, if the need arises, there is no reason not to machine my own from aluminum. The ESC heat sink is originally from a 2.4GHz @ 500mW video Tx. Since I use 900Mhz video, no need to keep a perfectly good heat sink on a video Tx that I do not use. The heat sink on the video Tx is actually an old computer processor heat sink. I cut it down, to fit the width of the video Tx. Since my video Tx is housed in an aluminum case (Range Video Tx), I was able to remove the top and screw up into the heat sink to secure it to the Tx housing. Of course, use thermal transfer compound or pads, such as those used as thermal isolators on common TO-220 transistors and other devices in such housings. For my camera, I have to drop the 11.1 battery down to 5 VDC. My regulator is switch mode and it does not even use a heat sink, nor is it located outside of the fuselage. It barely gets warm to the touch. The camera does not draw nearly the current of a 500mW video Tx. But, since you are going with a linear regulator, expect some heat. A TO-220 case style linear regulator is good typically for up to 1.5 A, when heat sunk. So, you will be drawing approximately half of the regulators capacity. If you locate your heat sink in an airflow, you can use the smaller, lighter heat sinks for TO-220 type devices. Sorry for the low image quality. This forum does not allow for large file sizes.
  6. Thorn3

    3.3 voltage reg for Aw633

    If you are going to use a fixed, linear regulator, it could be in either an SMD or To220 case style. Either one, can be hard wired directly to the pins. Since it is a fixed regulator, you would not need a PCB for it, as no support components would be needed, unless you want to thread the power lines through something like a ferrite, toroidal core, to reduce power spikes. Filtering with .1 to .01mF capacitors would typically be needed if the power lines are 6" or longer. A simple heat sink on the regulator is all you need. No PCB. Just shrink wrap over the pin/wire connections. You would not have to put the regulator directly on the Tx board. I don't. I use a switch mode, but hard wire to the pins instead of doing an on-board regulator. Power wires run out to the video Tx. Works well, with no interference.
  7. Thorn3

    Car Mounted Steadicam

    This does clear things up quite a bit regarding the use and environment of the vehicle. It does make engineering it much easier as well. I do believe that machining your own parts would be the most economical way to do things. Prototype machining or one-off design and machining costs a fortune, if you have to pay someone else to do it. In fact, I have my own machine shop for this very reason. I design and prototype various devices. If I had to pay another company to do it, it would be far beyond my budget. Paying a company to do it is only practical when such prototyping and development leads to a product line where thousands are expected to be manufactured and sold. Certainly use belts instead of gears. You can accomplish reductions such that you would need and have an almost whisper quiet drive system. Coils in brushless motors can whine, so be sure to insulate the motor noise, or suppress the coil noise with a feedback audio circuit (noise canceling)which is basically just a microphone circuit, amp and speaker that picks up the motor noise and plays it right back at the motor, 180 degrees out of phase. It will help to cancel out much of the audio being emitted by the motor itself, by a relatively high percentage. Back in the day, a belt mounted steady cam mechanism allowed us to run down a forest path with little image instability. So, with a slow crawler such as you need, for intermittent use and a steady cam mechanism, you could keep it pretty simple and cost effective. Provided you do the work yourselves through friends or associates. Certainly in any case, go with a fully independent suspension. Instead of using bevel gears to transfer power from a drive shaft (fore and aft) from the transfer case, use a belt instead. So not only can your reduction be belt driven, but so can your transfer to each wheel. Straight toothed bevel gear boxes are expensive and noisy. Not to mention the cost of helical gears! Better still, but more expensive in some respects, is to use independent drives. One motor and belt reduction per wheel. An encoder, be it magnetic or optical, could send feedback to the driver circuit that controls all four motors. This way, you don't have to deal with differentials or posi-traction drives. A fully independent suspension, with independent motors per wheel will give you the most stability and control. But then again, at a higher level of complexity and cost. The gain from this approach would be a superior machine however. The cost would not be so much more however, provided you have a robotics enthusiast on your team to help with the motor driver circuit and programming. To keep costs way down, get two old computer mice. Each has two optical encoders in them. Use them! Just shield the diode and receiver assembly from ambient light. I personally, would use as many aluminum extrusions as possible, to build the chassis. This will help keep costs and initial machining down to a minimum, yet offer structural integrity. I would then use one brushless out-runner motor, per wheel. An out-runner by nature of its design, is a reduction on its own. A low Kv out-runner, can then be coupled to the wheel using a timing belt. Use the smaller timing pulley on the motor and the larger on the wheel for further reduction. This will put the drives right on top of the wheels, allowing you to have optimal chassis clearance possibilities and a truly independent suspension and drive system. You could even cut costs even further, by using four, surplus stepper motors. With a microstepping drive circuit per motor, you can achieve precise movement of the vehicle. Both motors and driver circuits are readily available, either new or surplus. Coupled with a closed loop optical encoder and a robot board, you could have a very effective motorized camera platform. With stepper motors, you would not even need a belt reduction. Stepper motors can run very slowly and quietly and are fully sealed. I would use optical encoders (shielded) to read rpm from each drive. This would then be routed to IO ports of a robot control board, which is readily available for a reasonable price. The robot board could control each motor at the same time, using the encoder inputs to know if one wheel is slipping, etc in respect to the other wheels. With an encoder on the steering and some clever programming, you could make each wheel act as though it were driven by a differential to account for differences in speed between an inside versus outside wheel in a turn, while at the same time, acting like a posi-traction drive, where none of the wheels would slip, as they unfortunately would with a common differential drive. Complete traction control. More complex electronically and a little more money, but well worth it if you are looking for something very practical for filming use in various environments/conditions. But, you will need someone to help you out with the programming and setting up the electronics of the robot board, such as interfacing it to the vehicle. For the camera mount, I would use a 'balance' plate that is controlled by three servos. One would control tilt left/right and one would control tilt fore/aft. A gyro would detect vehicle tilt and automatically compensate by tilting the camera mount plate to accommodate changes in terrain angle, keeping the camera level. The third servo would control pan. The vehicle could potentially encounter a situation where the chassis will pivot right or left in respect to direction of travel, due to ground surface conditions, like a car sliding sideways on a snow covered road, slippery leaves or roots, sand etc. A gyro could control the pan servo, keeping the camera facing the intended direction of travel, even if the vehicle chassis has pivoted. Since each wheel is independently controlled, you could have the vehicle pivot itself out of such a rotation by controlling the direction of rotation of each wheel, much like turning a tank. This way you would not have to steer, while going forward, to correct for deviations in path. You could literally turn or rotate while in place, before moving forward again. If you are feeling especially creative, you could use a common, hobby GPS unit, interfaced to the robot board, to coordinate stop and go travel of the vehicle. Travel to X coordinates and stop, etc. This would add a certain degree of automation to the vehicle, if such a thing is desired. There are many, many options to such a camera mount. It all depends on your imagination, budget and utilization of as many readily available components/resources and having some clever people on your team. I am working on several products right now, so I don't have the time to help you out much more than offering ideas. Although, I do have to say your project interests me from a technical challenge point of view. I sincerely hope some of the ideas can help you out.
  8. Thorn3

    Car Mounted Steadicam

    I doubt highly, that you will be able to build such a vehicle for less than $1,000. I did quite a bit of set work and EM model work for ILM some years ago. What you are asking, is a complex piece of machinery. First, it will have to have some weight to it, to reduce 'bouncing' and allow stabilizers to react more smoothly. You would also need to use a completely belt driven primary reduction drive, to reduce noise and vibration. Use belts and appropriate stacked pulley ratios to achieve the top end speed and torque that you require. Use a brushless out-runner motor to drive it. Encase the motor and gearbox in a sound insulated casing and rubber isolator mount the drive to the chassis to prevent any vibrations from causing vibration to travel to the steady rest assembly. The suspension should be completely independent, not a solid axle type like your picture shows. If you want all terrain capability, independent suspension is the only way to go. Otherwise, if one wheel goes down, one will go up. You will upset the balance and attitude of the entire chassis. You would wind up with three wheels on the ground instead of four, disrupting the balance and thus stability of the mount. Of course, four wheel drive. In your four wheel drive system, use belts where you can. Where you cannot, use helical gears, not spur gears. This will run smoother and with less tooth impact, causing less noise and vibration not to mention heat. We are talking serious money here. Honestly, using an RC vehicle will pose you many problems in filming. There will be no real escape from bumping around, no matter how well you design and build the vehicle. Stabilization electronics development and components alone, will run you several thousand dollars. Especially for use in unusual terrain. If filming can be done in shorter takes, you should use a rail system. A simple mono-rail or dual rail made from pipe and flanged bearings would hold a platform that would ride the rails with far greater stability. In fact, the filming would be as smooth as riding on a smooth floor. With a properly designed aluminum trestle or saw horse type mount, the rails could be easily transported from point to point, to film as you go, along a very long path. Another idea would be to use several tripods, with adjustable legs, to hold a single, round rail. Pivot the camera mount plate sideways and mount the rail mounting bracket to it. You could then make a vertical camera mount post, that is counter weighted to hold the camera in a fully vertical position, as the bearings ride along the rail. You could easily attach the rail to the tripod mount plate with the use of a simple bolt, that would hold the rail (horizontally, in reference to the mount plate on the tripod) a few inches from the tripod mount plate. This way, the camera could be powered by a belt driven drive that is much smaller, less expensive and far more stable. The camera drive mechanism could consist of the three bearings to ride the rail (rubber to reduce noise), and a rubber hobby aircraft wheel or similar, driven by your belt driven gear reduction. The rubber drive wheel would simply ride the rail. Use a rubber pinch wheel (spring loaded) that is free running, to help traction of the drive wheel on the rail. If you use longer lengths, of smaller diameter plastic tubing, you could bend around turns much easier than using aluminum or steel tubing. You could couple tubing ends with internal couplers that simply plug together for easy assembly, disassembly and transport. This will enable you to film your takes in various locations, with arcing turns, dips, etc., to follow terrain. I hope these ideas have helped you in some way. Honestly though, an RC vehicle will not give you a stable filming platform, at any speed, for so little money, in all terrain conditions. You really should use a cable, or rail system to avoid the terrain altogether.
  9. Thorn3

    3.3 voltage reg for Aw633

    I also prefer the switch modes. All of my FPV aircraft use switch mode supplies. My camera uses 5 VDC, the mic with built in pre-amp uses up to 12 and so does the 500mW video Tx. So, my switch mode is used on the camera only. I use a separate battery for the camera system (camera, mic and Tx). It is an 800mAh LiPo, 3 cell (good for four flights). The aircraft uses a 1500mAh 3 cell. Funny that the two batteries weigh the same as one 2200mAh battery. A good balance. I don't have any lines of interference. Although I have seen this when people use the same battery used to power the other functions of the aircraft ie: motor, ESC etc., for their camera system, or the regulator was within close proximity to other devices. I (presently) place my switch mode relatively far aft in the aircraft, to avoid any EM fields that could be picked up by any servo, camera or other lines. Otherwise, surely as MR.RC-Cam put it, filter it out if need be. I was going to post earlier, after the diode suggestion, that if a one cell were being used, then a simple diode voltage drop would be appropriate (only .4 volts drop needed). But, no mention was made as to the other components (at that time) in the video system and their power requirements, nor the main supply voltage, so I did not comment. But... there may be hope soon gentlemen. My partner and I are finalizing a new switch mode regulator series. Efficiency is presently 95%. These supplies are being designed specifically for RC use. They do not induce the same issues into RC aircraft electrical systems like older designs do. I will post when and where they will be available. They are presently in the field testing stage. I have to abuse a few of them in some of my own aircraft for a while first.
  10. Thorn3

    3.3 voltage reg for Aw633

    Brett, I personally have not used or experimented with this module, so I do not know how sensitive its input voltage requirement is. I looked at the documentation for the Tx and it did not indicate a voltage input range. Due to this, I would assume they mean the input should be precisely 3.3 VDC. If this is truly the case, then you could easily use an LM317T, adjustable output, linear voltage regulator. Use a pot when setting up the regulator circuit and adjust to exactly 3.3 volts. Either use a dab of adhesive to hold the pot at value after adjustment, or replace the pot with a permanent value resistor. I am assuming that like the Tx module, you will be using all SMD components? This is why I suggest a linear regulator chip, such as the LM317T. It is available in SMD form (as is the pot, etc) and will integrate into your PCB easily. Be sure to use a supply voltage to the regulator chip, that is at least 3 VDC higher, than the expected output voltage. In this application, it would appear that at least 6-9VDC in, would suffice. I do not prefer the use of linear regulators generally. Typically, when possible, I would use a switch mode. Dimension Engineering (dimensionengineering.com) has adjustable output switch mode supplies. They are reasonable in price and just might be what you are looking for. Switch modes are more efficient than linear supplies, although larger and more complex. The smaller ones are not much larger than a linear regulator in a T0 220 housing. Robert
  11. n3m1s1s: Thanks for liking my antenna and tripod design! This antenna was made as a 'one-off'. It was designed around available stock materials laying about. Now that the design is completed, it would be possible to make more. However, with my machines, which are manual machines, it would take some time to machine all of the parts, as it did with the first one. With the cost of new materials, worthy of being sold to someone, machining and fabrication time, shipping/import costs to the UK, etc... it would be much more financially feasible for you to make one there in the UK. I make things the way 'I' want them, which usually means going way overboard with design. Tolerances on most of the parts are .0005"! Everything would have to be scaled down for a higher frequency, including the tripod itself. As doofer mentioned in his follow up post, this sized antenna could not be used in the UK anyway. The 2.4GHz antennas are much smaller and much easier to make. I am sure that a simple camera tripod, possibly cut down to keep the antenna close to the ground would do well for a 2.4 GHz antenna. Much more cost effective as well, compared to my manually machining specialized parts for you, then shipping them to the UK. I am sure that any sheet metal shop in the UK, would cut the sheet steel for you according to the dimensions for the patch antenna found in the RC-CAM website. Then it is a simple matter to install the SMA connector and glue in some spacers. This puts me in a bind! I would like to help. I really would. But, would it be financially feasible? My setup is complex and not easy to make. One option would be to use lamp parts. The base for a lamp should be more than enough to act as an anchor for a vertical pipe, to keep an antenna close to the ground. Typically, all kinds of all-thread tubing, with nuts, for lamps can be found in hardware stores, as well as larger tubing to fit over them, as is seen in many lamps. Amazing what you can do with lamp parts. I have a friend here in Arizona that has a CNC mill. I do have another design for a small tripod that would be perfect for higher frequency patch antennas. It is capable of folding up flat. Let me talk to my friend and see how much it would cost for him to machine the parts from aluminum. Let me get back to you on that. It is possible, that if I can have the new tripod design made at a reasonable cost, the antenna and tripod could be mailed in a standard sized box for a set price, anywhere in the world. So, it just may be possible. Let me examine the costs first, then get back to you. For me to have my friend machine one-off parts, the costs are higher. If more people were interested in a specialized, collapsible design, with the patch antenna included... then the costs would come down quite a bit.
  12. Picture of goggles. These are wired as explained in the first post, using a computer monitor cable. The input power lines are first run to the onboard power input jack, that is native to the goggles. This way, the input power from the new cable, goes to both the Rx board as well as the original input power jack. This way, the original input power jack can be used as an 'output' power jack, to power any accessories that may be added, such as head tracking devices etc. Presently, the input power is supplied via a 3000mAh NiMH battery pack, at 8,4 volts. Any input power can be used, up to nine volts. The goggles internal Rx board, contains a 7805, linear voltage regulator on board. This converts whichever input voltage is applied, either the 8.4 from a NiMH battery pack, or line powered nine volt supply, to 5 VDC for the goggles circuits. The end of the cable, shows both the input power connector and the video input connector (RCA), which plugs into the video Rx. I plan to make a simple 7809, 9 volt linear regulator circuit, to be built into the video Rx. The power plug on the main cable will be changed to accommodate a more appropriate jack that will be installed in the video Rx housing. This way, the 12VDC powering the video Rx, will also power the 7809 regulator, which will provide power to the goggles, instead of having to use a separate battery for the goggles at the Rx end. This way, in the field, all that is needed is a single sealed lead acid, 12 volt battery to power my entire system, as well as provide a convenient means to re-charge my flight batteries.
  13. I can only add two pictures at a time, so multiple replies will be used to show more images.
  14. Hello all, The 900MHz patch antenna is a common arrangement, as described in the RC-CAM site. The backing to the antenna ground plate is made from Acrylic left over from another project. It's goal is to offer the base rigidity to the ground plane and antenna in general, as well as offer a means to provide pivot and angle adjustment. The legs are made from .625" ID electrical conduit. Bronze sleeve bearings were placed into the ends, to allow the leg extension rods to move in and out smoothly and without slop. The leg extensions are unfortunately low quality steel, .500" rod (turned in the lathe for more accuracy). Cold rolled would have been better, but I didn't have any laying around. The leg extensions are made from steel, to provide a good surface for the bronze sleeve bearings, as well as add weight to prevent gusts of wind from knocking over the antenna. The purpose of the extensions is to take into account, irregularities of the ground. The ends of the leg extension rods were turned down to .250" Dia, X .500" long. These ends fit into drilled out rubber stoppers. The locking nuts are made from brass thumb nuts. I needed thumb screws, but did not have any. Instead, I used some brass screws, as all thread to give the nuts screw ends. The screw threads were soldered into the nuts. The ends of the threads were smoothed out as to not mar the surface of the extension rods. The screws are located such that a person can adjust the leg heights without having to move around the antenna. All can be adjusted from behind the antenna. The 'umbrella' type mechanism is made from hobby, square, brass tubing. This assembly insures that each leg is in proper reference to the others, keeping the legs equidistant. It works just like an umbrella. This assembly was silver soldered, using a Smith Little Torch. Although, any hobby torch would do. A brass rod was used for the main pivot for the antenna. A brass washer specially made for it, was soldered to the end of the rod to act as a 'head'. The other end of the tube has a turned down, brass nut soldered into it. A brass screw with lever arm was made in the lathe, to adjust tension for adjusting the angle of the antenna plate. The antenna plate pivot bracket, is aluminum sheet, drilled and bent for the purpose of allowing the antenna plate to pivot from horizontal to a bit less than 45 deg. The main leg pivot head was machined from some left over 2" OD 6061-T6 aluminum round stock. The tongues for the legs were machined from .750" Dia, round stock. They extend into the legs .750" and are pinned in place with spring pins. Washers were made from .010" thick Nylon sheet that was once used as a strap for... something. Had it laying about the stock pile. All metal to metal surfaces use Nylon washers to prevent wear or binding. I plan to modify the SMA cable further, to include the use of a 90 deg., connector on the antenna end. This way the connector will allow the antenna to pivot freely all the way around, as it will keep the cable away from the tripod more efficiently. Each end of the cable is male. The cable used, was taken from an RF antenna intended for wireless uses on my computer. Since I don't use such wireless devices on my computer, the cable was used instead for the antenna project. Both ends were female. I modified them to be male. The cable is 3' long. Tests show the antenna works very well. It is low to the ground, easy to set up and adjust and cost very little to make. Most materials were already in the shop. It is not a design that people without shop machines would make however. A mill and lathe were used. The antenna is also very portable, as can be seen in its folded up position. A similar setup can be made using only commonly available hobby materials, without machines. With some modifications to the design of course. Well, I hope you like the design of my antenna. I enjoyed reading through this site and found the information to be very useful. I use a Fat Shark, head goggle set, modified of course. I hard wired a computer monitor cable directly into the goggles. This allows the ability to provide video, audio and power, all in one multi-shielded cable with built in toroid, as is common on monitor cables. The cable protrudes out of the top of the goggles, allowing the cable to easily lay over the shoulder and not down the side of the face like side burns, as with the original goggle setup. I use a 500mW video Tx from Range Video and their dual output Rx. Other FPV projects are in the works.