5.8ghz micro cloverleaf bending jig
Description
1/4 wavelength 5.8ghz cloverleaf bending jig. This allows you to create an LHCP or RHCP cloverleaf antenna for 5.8ghz that's small enough to fit inside a tiny whoop canopy which will keep it safe during crashes while still being well under 1 gram AND give you all the benefits of circular polarization. ###How is this 1/4 wavelength and what does that mean? For the full explanation, see the antenna theory website linked below, however, basically a the active element of an antenna ideally should be the same length as the wave of a signal. (speed of light/5.8ghz = 51mm) 51mm is really long though and a 1/4 of that works nearly as well so... we typically have a ~<13mm antenna if it's something like a linear whip antenna. As for cloverleaf antennas, they're usually not called by a fractional wavelength name. The radius of the leaf is 1/4 wavelength though and the lobe is 1/2 wavelength making the entire active element piece ~1 wavelength... so I'm going with the lobe which on a normal cloverleaf antenna is 1/2 wavelength and with this antenna it's 1/4. Until I know better, that's what I'm going to call it. ###Does this actually work? I don't have an SWR meter but... First, my testing (See my range testing video) says it works. (Test Video: https://www.youtube.com/watch?v=bUPrxrfwc2w ) Second, a poorly tuned antenna doesn't radiate and reflects the energy from the VTX back at the VTX that has to be dissipated as heat. After flying a full pack around my house, I used an infrared thermometer to measure the temp of my VTX while it was still plugged in and it was showing 94F.... which is lower than body temp, and quite cool for your typical VTX. So... I'm going to say it works, but it's up to you to do your own testing. I'd suggest plugging in your current antenna and letting your VTX heat up on your bench for a few minutes. See how hot it gets. Then after putting this antenna, try that again. If it's cooler, great! If it starts to get really hot (like too hot to touch) don't use it (and check your measurements) A coworker with a friend with a network analyzer has offered to measure these. When that happens I'll update the details here. #Instructions: 1. First, straighten your wire. It doesn't have to be perfect you just don't want any sharp bends. 2. insert the wire into the straight slot and bend against the side of the jig as shown in the pictures as tightly as possible. Before you move on, measure the bend from the tip of the wire to the center of the bend as best you can. It should be ~6.5mm. If it's short, straighten the wire again and insert it in the slot. Hold the wire with some tweasers and heat with a soldering iron. Wiggle the wire a bit to melt the plastic of the jig enough so that when you bend, the length is ~6.5mm. 3. With the still in the jig from step 2, now bend again as tightly as possible against the bottom of the jig as pictured. 4. remove the wire, now in a C-ish shape from the jig and place in the right angle section as pictured. Bend the wire as shown as tightly against the jig as possible. 5. Now place the wire in the curved form section as pictured and slowly squish the wire into shape. A set of flat pliers helps here. 6. snip off the excess wire from the end of the jig as pictured. 7. pop the wire out of the jig and you have a correctly formed clover. 8. Make at least 3 for each antenna. #Assembling the antenna See RCModelReviews Youtube video as it builds the exact same antenna, just a larger version. Video: https://youtu.be/yohKRzMAJAg ###Wire: .5mm copper wire. I stripped this out of CAT5 cable I had laying around. Note some cat5 is stranded, so if you don't have sold core laying around, buy 24awg sold core wire. I think you can get it by the foot at a local hardware store. ###What coax to use? Most VTXs that have U.FL connectors have the larger IPEX1 version. You can buy these for cheap on eBay or Aliexpress (When I searched Amazon I could only find the IPEX4 style and that connector is smaller) Anyway, the coax wire that comes with that antenna is perfect and bonus if you need the U.FL connector for your application. This wire also works for MMCX connectors. if your VTX uses solder pads, this antenna wire works fine for that as well. #Why would I want to do this? Circular polarized antennas reduce issues with multipathing. This is when your signal bounces off something and your receiver picks up the primary signal and the reflection slightly delayed. By using a circular polarized antenna, say RCHP, the reflection will be left polarized and an RHCP antenna will be far less likely to pick it up. If you want to learn more, check out http://www.antenna-theory.com/ Another reason you would want to do this is if you're organizing/participating in Tiny Whoop races. Traditionally only 4 pilots can fly at the same time, however, there are channel setups that can support up to 6 pilots flying at the same time if people are on the correct channels and also correctly using RHCP vs LHCP.
Statistics
Likes
15
Downloads
0