The wpx operation was very casual.\u00a0 I spent a lot of the time just tuning around the bands listening.\u00a0 The beginning of a CW contest are always too fast paced for my mediocre CW skills, and taking a mental picture of band conditions was more fun.\u00a0 The bands sounded “brighter” than at any time in the past couple of years.<\/p>\r\n
As a quick-n-dirty mod, I used a second feedpoint to attach the efhw to an 80m folded counterpoise. This is to allow 80m operation by shifting the feedline and using a jumper to bypass the transformer.\u00a0 \\\/expanded description below\\\/\u00a0<\/em><\/span> This gave the antenna resonance on 3.625Mhz.\u00a0 To drop the resonance into the CW segment I wound a 6 turn coil on a 1.25 inch form.\u00a0 That is inserted at the bypass jumper with faston connectors.\u00a0 To raise the resonance to somewhere near 3.8Mhz a 3kv capacitance of about 500pf does the trick.\u00a0 80m was good-to-go.\u00a0<\/p>\r\n So as luck would have it, the good band conditions made testing on 80m less useful than I hoped.\u00a0 20m was open until at least local midnight (0400Z), and probably was open to somewhere all night.\u00a0 On Friday night few ops moved down as far as 80m with 20m and 40m providing a bottomless pit.\u00a0 It did allow for gathering some info from the RBN spots, which look like either the band was open in famous fashion, or the EfHW was doing a decent job.\u00a0 Maybe a bit of both, as the 80m spots looked pretty good, as well as showing up on some skimmers not normally hit with permanent inv-vee.<\/p>\r\n The antenna was also able to work most of the stations heard on 10m.\u00a0 That’s a change over the few other recent outings.\u00a0 15m was a bit of a mixed bag.\u00a0 20m responses were comparable to other experience with dipoles.\u00a0 40m seemed unusually good, but it may be more due to the very quiet sounding band conditions.\u00a0 On Sunday a short 40m run coincided with the band opening to Europe, and it is shown in the RN spots.\u00a0 The RBN spots started out as US only.\u00a0 By the end of the 60 minute run there were several EU RBN stations showing 20-30db SNR, and a slow growth in calls from EU stations.\u00a0 Too bad the contest was at its end.<\/p>\r\n The first attempt to use on 80m, the transformer was shorted out of the circuit and the radial attached to the ground lug.\u00a0 This did not work as expected, and more testing is needed,\u00a0 The first thought is the EFHW 120pf capacitor to ground needs to be removed from the circuit for the vertical.\u00a0 The quick field expedient kludge was to move the coax to a feed point not sharing ground with the EFHW box.\u00a0 The first test used a single radial cut for 80m. In that configuration the antenna resonated a bit below the 80m CW band segment.\u00a0 Resonance could be shifted upwards by inserting a series capacitance at the base of the driven element.\u00a0 SWR was very favorable at each resonance point chosen with about 150 to 200 kc of 2:1 bandwidth.<\/p>\r\n A second option was tested, using a folded counterpoise instead of the single full length radial.\u00a0 In this configuration resonance was at about 3.625Mc.\u00a0 A 6 turn coil inserted in series in the driven element dropped resonance to 3.54Mc, and capacitors can be used similarly to raise resonance to upper SSB band segments.\u00a0 In this configuration the best SWR was about 1.8:1, and bandwidth more limited.\u00a0 Easily stretched moderately with an antenna tuner.<\/p>\r\n The folded counterpoise version was used in the contest with great success.\u00a0 This is going to require a lot of testing to decide if either version is a better 80m performer.\u00a0 For my purposes, the FCP version is compact and easy to set up, so it will be the one used.<\/p>\r\n Potential next project: using relays to allow remote switching, both for the transformer taps when in EFHW mode, and for switching components needed to operate as a standard vertical.\u00a0 Hmmmmmm<\/p>\r\n ????photos coming 2021-07???????\u00a0<\/p>\r\n The kludgy fix for adding 80m was an outstanding low effort method for stretching the single driven wire to use on another band.\u00a0 The cost is the time used adding the FCP radial on deployment and later some manual band switching while operating.\u00a0 It would not take a lot of effort to add a few relays to allow remote switching – a possible future project.\u00a0 This EFHW would make an outstanding option for quick deployment by folks stuck in enemy territory where permanent antennas run up against tyrannical HOA rules.\u00a0 The whole thing can be deployed or removed easily in less than 15 minutes with a bit of planning and practice.<\/p>\r\n Having a tapped transformer allows a very good match on each of the five main bands of interest in contesting.\u00a0 I think using the 80m option using a folded counterpoise and 40m EFHW driven element as an inverted-L vertical the seems to be at least comparable to the version with the loading coil and 80m tail extension.\u00a0 It is easy to deploy and switch, and inserting a small coil at the base was easier than tuning the 80m loaded EFHW.\u00a0 An 80m FCP is 32 feet long, so it is fairly compact also.<\/p>\r\n","protected":false},"excerpt":{"rendered":" Very casual <\/p>\n The wpx operation was very casual. I spent a lot of the time just tuning around the bands listening. The beginning of a CW contest are always too fast paced for my mediocre CW skills, and taking a mental picture of band conditions was more fun. The bands sounded “brighter” than at any time in the past couple of years.<\/p>\n As a quick-n-dirty mod, I used a second feedpoint to attach the efhw to an 80m folded counterpoise. This is to allow 80m operation by shifting the feedline and using a jumper to bypass the transformer. \\\/expanded description below\\\/ This gave the antenna resonance on 3.625Mhz. To drop the resonance into the CW segment I wound a 6 turn coil on a 1.25 inch form. That is inserted at the bypass jumper with faston connectors. To raise the resonance to somewhere near 3.8Mhz a 3kv capacitance of about 500pf does the trick. 80m was good-to-go. <\/p>\n Dirty Tricks Department <\/p>\n So as luck would have it, the good band conditions made testing on 80m less useful than I hoped. 20m was open until at least local midnight (0400Z), and probably was open to somewhere all night. On Friday night few ops moved down as far as 80m with 20m and 40m providing a bottomless pit. It did allow for gathering some info from the RBN spots, which look like either the band was open in famous fashion, or the EfHW was doing a decent job. Maybe a bit […]<\/p>\nDirty Tricks Department<\/h5>\r\n
The 80m Inverted-L Mod<\/h5>\r\n
Conclusions<\/h5>\r\n