A person emailed me to ask if I could take SWR readings at the rig without a tuner. Since my antenna analyzer is non-op due to the AM station nearby. The feedline is about 140' of LMR-240.
Here is the indicated SWR at the 7300: 1.810 1.2:1 1.830 1.3:1 1.850 1.5:1 1.870 1.8:1 1.900 2.3:1 1.940 3.0:1 Todd - NR7RR On Fri, Dec 28, 2018 at 7:30 PM Todd Goins <tgo...@gmail.com> wrote: > Charlie, > > Yeah, I know the 100w is not ideal. This is night #2 with the elevated > radials on the 100' vertical. I spent every day last week trying to use the > 100' vertical against my buried radial field. It was horrible on transmit > and mostly deaf (high noise) on receive. The attenuator didn't help, it > just isn't hearing stations. My 43' vertical top loaded with 90' of > horizontal wire is way, way more effective. > > I'm using a 230' BOG as my primary receive antenna right now but I can > switch in the transmit antenna to listen just by throwing a switch. > > I'll stick with this 100' antenna for a while and try to use it this > weekend on the Stew Perry but I have a feeling I'll be back with the 43' > before it is over. > > Thanks, > 73 > Todd - NR7RR > > On Fri, Dec 28, 2018 at 7:19 PM charlie carroll <k...@k1xx.com> wrote: > >> Todd: >> So, I might shorten the antenna up a bit to get the lowest SWR point a >> bit higher in the band. But, as it sits right now, your SWR is not >> indicating a problem. You're talking only a 100 watts which gives you at >> least 1 strike. I would play with it as is for a few days and get some >> idea as to how well you are hearing and how well you are transmitting. >> >> Without detailing you, 160 is a place where you need patience and/or a >> low-noise receiving antenna. Plus, you also need to know whether you are >> being affected by local noise sources. Another reason why I encourage you >> to spend more time evaluating the antenna. >> >> 73 charlie, k1xx >> >> On 12/28/2018 10:07 PM, Todd Goins wrote: >> >> Hi Charlie, >> >> I can measure SWR at the rig. Feedline is about 140' of LMR240 coax. >> >> SWR at: >> 1.810 1.2:1 >> 1.830 1.3:1 >> 1.850 1.5:1 >> 1.870 1.8:1 >> 1.900 2.3:1 >> 1.940 3.0:1 >> >> I wasn't too worried about the choke situation but I connected in-line >> what I had on hand, figured it wouldn't hurt. Mike had just asked what I >> was using so I let him know. I'm not having any symptoms of RF in the shack >> but I'm only running 100 watts. >> >> 73, >> Todd - NR7RR >> >> >> On Fri, Dec 28, 2018 at 6:56 PM charlie carroll <k...@k1xx.com> wrote: >> >>> Todd: >>> So, what do you expect the air-wound choke to do for you? Many, many, >>> many antennas operate fine without a choke. Don't get yourself wrapped >>> around the axle that the antenna won't work without a "correct" choke. >>> >>> What's SWR are you measuring at the transmitter? How long is the >>> feedline? Sure, it would be better to know what the Resistance and >>> reactance are. But, SWR will give you some idea as to where you are at. I >>> think right now, you don't really know what your ground truth is. Tell me >>> the SWR at 1.8, 1.85, 1.9, etc. >>> >>> 73 charlie, k1xx >>> >>> >>> >>> On 12/28/2018 9:30 PM, Todd Goins wrote: >>> >>> Hi Mike, >>> >>> Oh, I would totally believe that the air-wound choke is ineffective at >>> 160m. It just happens to be what I had available to use when I rigged up >>> the elevated radials in the cold rain yesterday. I figured I'd put it in >>> line just in case. >>> >>> Thanks for the choke links, I will read the info on those sites. >>> >>> The air-wound choke is what I'm using when I'm feeding the antenna using >>> the elevated radials. When I was testing using my buried radial field it is >>> a different setup. There I have a DX Engineering radial plate that neatly >>> ties everything (remote tuner, and DX Engineering Maxi-core Feedline >>> Current Choke) together at the feed point. >>> >>> Thanks for the comments and info. >>> 73, >>> Todd - NR7RR >>> >>> >>> On Fri, Dec 28, 2018 at 5:57 PM Mike Waters <mikew...@gmail.com> >>> <mikew...@gmail.com> wrote: >>> >>> >>> Hi Todd, >>> >>> I'll bet the farm (if I had one) that your air-core choke is ineffective. >>> Take at look athttp://www.karinya.net/g3txq/chokes to see what I mean. >>> >>> A very, very good common mode choke is the one I have on mine, >>> fromhttp://audiosystemsgroup.com/RFI-Ham.pdf. There is no better material >>> written on this subject, either in print or on the Internet. >>> >>> 73, Mikewww.w0btu.com >>> >>> On Fri, Dec 28, 2018 at 7:34 PM Todd Goins <tgo...@gmail.com> >>> <tgo...@gmail.com> wrote: >>> >>> >>> ... I do have a common mode choke at (near) the feed point. It may or may >>> not >>> be effective at 160m. It does work on 10-80m. It is about 25' of RG-8 coax >>> wrapped around a 4" PVC pipe as a form. Perhaps not ideal... No RF noted >>> in >>> the shack. >>> >>> 73, >>> Todd - NR7RR >>> >>> >>> _________________ >>> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector >>> >>> >>> >>> >> _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector