Putting the HT in your pocket is the worst position for Body Fade. The radio harnesses work very well to avoid Body Fade. Keep in mind that all you need to do to avoid Body Fade, is to change the orientation of the antenna, and move it very slightly away from the body. When the antenna orientation is changed to diagonal angle or perpendicular to the body, then Body Fade is reduced dramatically. Body Fade / Body Shield happens when: Using a short ducky antenna Ducky antenna is parallel with body HT is held within 1 inch of body On 2 meters, you can avoid Body Fade with a ducky antenna at least 12 inches long, but don't get it fouled in the rigging or prop
WB4IME said "My comments on the PPG Forum were all positive, educational and supportive. " Dear WB4IME, As an uninvolved observer reading your comments on the Paramotor group, I was honestly embarrassed for Amateur Radio. You posted false information both here on QRZ and there in the Paramotor group. You intentionally tried to scare people. I'm sure you probably noticed that you got some negative reactions Potential licensed hams, as well as licensed hams, in the Paramotor community were repulsed. Friendly outreach after-the-fact can't fully repair that first impression of nasty behavior.
Thanks for the suggestions. The motor cages can be disassembled for transport or packing so there would have to be some kind of quick removal concept but the top of the cage is one option. I'm not sure that the cage as a ground plane would be a good idea (possible spark plug noise and radiation pattern issues) but if the antenna system included it's own ground plane system, I see it as a good location. Co-locating the strobe and ensuring all wires and parts could not interfere with flying or even a reserve pull would need some special attention. Trailing the length of coax is also an idea I often go back to but then there's that big fan problem and keeping the antenna away from it. The Right now I'm envisioning a length of coax, (probably something much thinner than RG58 like RG174 or RG316) run up one of the lines with the shielding removed for a quarter of a wavelength down from the tip (end fed vertical dipole?) The lower part of the cable would form a ground plane. A balun may be needed half a wavelength down from the tip to keep the longer ground side of the antenna from affecting the tuning but I need to talk with someone with more recent experience in antenna construction. The antenna could remain permanently attached to the wing with perhaps the radio end being velcroed in place during pre-flight. Maybe with a "pull-apart" connector somewhere in the line in case the pilot needs to disconnect quickly from the wing. Ideally the cable would be attached so that the feed point - balun if used - would be above the pilots head. (The wing is always stored detached from the motor but you can see the attachment point in my photo just above the inverted V shape to the right of my face. The red band above the tip of the inverted V is the lowest part of the wing.)
Thanks Dan. That was part of my thought behind asking if any hams have ever heard any PPG or PG chatter. There are certainly non-ham PPG pilots watching this thread (and I expect to get clobbered there if I say something out of place here) but letting them know that interference is a real thing will certainly go a long way towards preventing it. Of course there are PPG pilots who don't abide our DBAD (Don't be a "dork") rule just like there are lids in the ham community. But I think most of the issues simply come from a desire to communicate, not a desire to interfere, and my hope that all PPG pilots will have a standardized (albeit defacto) easy set of steps to follow which will end in successful and legal communication with other pilots and the ground, and that it becomes something that they simply always fly with - like a helmet. Interesting. If a cheap antenna (or even multiple antennas) can be safely attached to one of the risers well above the body, that will fix a bunch of issues including how we move around when flying (we sometimes shift our weight to turn), keep a (mostly) vertical polarization, allow us to keep the radio in pockets where we can easily access and see them if we need to change frequency or other settings, eliminate the Baofengs crappy antennas, and maybe even allow us to go to extremely low power which is a batter saver, finals protector, and helps reduce interference with ground stations (assuming GMRS use). The antenna will probably even be cheaper than a harness but that's still an idea to be explored. One of the pilots with whom I often fly has a much better version of one of these harnesses and I will see if we can do some testing together.
Thank you for your opinion on this Bonnie Thank you KK4RSD for your input as well. I have asked the admins to consider removing Jim from the Facebook forum. He continues to post the non-existent threat of draconian fines, recently even going so far as to compare the intermittent illegal use of ham frequencies by the PPG pilots with the well known and well documented extensive disturbances on 7.2 MHz. This is uncalled for and helpful to neither the PPG nor the amateur communities.
So is this to say that WB4IME should not object to the presence of interlopers on our bands? I don't see it as "being an inquisitor of the amateur service". He simply objects to the presence of unlicensed operators ON our authorized bands. I am not an inquisitor of anything, but I vehemently object to unlicensed operators on any amateur band and also on other licensed or duly authorized bands I operate. I strongly objected to them on the 10 Meter band and actively sought to stop truckers from filching 28 MHZ--and will still do (tho I don't think we get the help we used to in that regard). I don't even give a rat's (fill in the blank) about what the "PPG" community does nor do I care about solving their communications problems; It is not for me to do! But if I DO catch one of 'em chatting on 2 Meters without call or license, I will turn them in so fast....................., and do what is needed to stop them. OTH, I will do what I can to help anyone who is interested in amateur radio for its stated and legal purposes. What I am reading here is a factionalized, pro and con forum either suggesting ways to remedy the situation or tacitly making excuses for illegal ops--even encouraging same. That I simply against.
For a non-motorized Hang Glider or Paraglider, an antenna attached to the riser rigging would be fine. But for a Paramotor, there is a really significant chance of prop fouling if (when) the coaxial cable becomes detached from the HT's coax connector while in flight! In a physically rough situation, the coaxial connection at the HT is a statistically common point of failure. We see this failure mode with miniature coaxial cable in mobile and pedestrian mobile installations. Perhaps some type of break-away coaxial junction could be utilized and the coaxial cable could be lashed to harnesses, to minimize the failure and the prop fouling. There is a way to modify a female or male BNC connector for break-away. The female connector: the locking pins are carefully partially filed down and rounded off. The male connector: the inner locking edge of the outer shell locking ring is ground down. The drawback of the BNC break-away mod is that it is not a very secure antenna connection. But, there is very little advantage to that type of riser antenna compared to a good flex antenna mounted directly on the radio, with the radio in a harness that properly orients the antenna.
Mark: Thank you for your comments. I believe we can agree to disagree on certains areas of the conversation and that is ok. By the way, posting a picture of 'grumpy ole Mr. Wilson no the PPG Forum was cute. I enjoyed that. Thanks for the humor.
Yep, something a lot like that. I think the exposed shield could simply be removed and the lower half of the cable would be the counterpoise. Or? Or would a balun be appropriate/necessary/idea to prevent the entire length of shielding back to the radio from being an active part of the antenna?
The folded back shield is the other half of the antenna. If you eliminate it, the match will be poor, and there will be lots of common mode current on the outside of the shield. As shown it is pretty much a center fed dipole, and should work well and cost practically nothing.
Mark : You have been inquiring about the installation of a mobile antenna for the foot launch PPG. Here are some designs that would be compatible with perhaps some minor adjustments ... Excellent method for PPG : http://chrusion.com/public_files/InvVeeAntenna4ULs_rev3.pdf Other methods : https://www.amazon.com/Pro-Trucker-Antenna-Mirror-Freightliner/dp/B01G4FYDYI https://www.amazon.com/WORKMAN-DOUBLE-GROOVE-ANTENNA-MIRROR/dp/B01GK49NM0?ref_=fsclp_pl_dp_1 https://www.rightchannelradios.com/products/3-way-aluminum-cb-mirror-mount-1 There are also loop antenna designs that work very well. I can visualize the use of the motor frame itself ( a natural loop ) as an antenna with very minor modifications. A number of the frames are sectional parts of a loop. Utilizing both the right and left sections beginning at the top center of the frame as the radials of the antenna ... in combination with the vertical portion mounted at the top where a strobe might be located would be effective. The challenge would be tuning the left and right frame sections to be resonant with the vertical ( whip ) portion. Sounds like an interesting antenna project. I also did a search in the Ultralight internet sites. There are a number of examples there that could be transferred to a foot launch PPG setup. Transferring the design to a Quad or Trike would be a snap.
I think an antenna like the inverted V in the first example would work, but just build half of it, and use the AL frame as a ground plane. Build the insulator from a scrap of nylon cutting board, as shown. Should work really well and cost near zero.
Instead of pulling the center conductor out of the side of the shield, try fanning the shield out a bit at the base point, where the insulation has been removed, and roll it back down the outside of the coax jacket, and tape it up that way. Make it a coaxial center-fed dipole antenna. For those still thinking 2 Meters, keep in mind that it is legal to do this on GMRS (with a license) and at GMRS frequencies, a full-length quarter-wave antenna is only about 5.75 inches. Let that hang straight down from the side your seat about one foot, and you have an omnidirectional antenna. Wire-tie it to the seat frame, or whatever. If you need a quick rip-away connection that stays secure, forget modified BNC, use metal Switchcraft RCA type connectors on your RG-174. Believe it or not, they are very close to 50 Ohm connectors.
Get an F female to female with a nut and make an AL "ell bracket" to screw to the frame. Get a RG59 or RG6 cable with push on connectors on each end. These come with VCR's, etc. and can be had at any thrift store. Then get an F adapter to your radio. Adapter goes on radio, F connector pushes on, cable goes to F to F coupler attached to metal strut. Strut acts as ground plane, you have a push on connector at either end of 6' cable. Antenna is made from scrap piece of TV cable with F connector already attached. Remove shield above connector, and cut to QW.
