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Total 15 documents matching your query.

1. [Amps] LP filter effects (score: 1): Author: smlx@earthlink.net (Steve Lawrence); Date: Fri, 15 Nov 2002 23:19:38 -0800; I have an old Drake 1KW LPF in line running 1500w output from an Alpha 87A to a TH7DX. It's worked fine for several years. I've pulled the LPF out of the line. At 28000 with 1500W out, the reflected; /archives//html/Amps/2002-11/msg00267.html (7,495 bytes)
2. [Amps] LP filter effects (score: 1): Author: g8gsq@qsl.net (Steve Thompson); Date: Sat, 16 Nov 2002 08:14:30 -0000; Assuming the power meter is between the LPF and antenna, it's difficult to see how the LPF could be increasing the harmonic level. Another possible cause is that your meter has poor directivity and h; /archives//html/Amps/2002-11/msg00268.html (8,093 bytes)
3. [Amps] LP filter effects (score: 1): Author: k2xx@swva.net (Joe Giacobello, K2XX); Date: Sat, 16 Nov 2002 10:25:33 -0500; Steve, my experience with the Drake LPF's is that after sustained use at 1.5 KW, they start to fail. Probably capacitor dielectrics are breaking down or something similar. They are really only rated; /archives//html/Amps/2002-11/msg00273.html (9,146 bytes)
4. [Amps] LP filter effects (score: 1): Author: rakefet@rakefet.com (Vic Rosenthal); Date: Sat, 16 Nov 2002 09:11:46 -0800; The extra 100 watts of reflected power could be harmonic energy above the filter cutoff. In other words, the filter is doing its job. Or some components have changed value and the filter's characteri; /archives//html/Amps/2002-11/msg00274.html (8,267 bytes)
5. [Amps] LP filter effects (score: 1): Author: rakefet@rakefet.com (Vic Rosenthal); Date: Sat, 16 Nov 2002 09:14:19 -0800; I assumed he had the meter before the LPF. That's the best place for it, since the diodes in the meter may generate harmonic energy themselves. Vic K2VCO; /archives//html/Amps/2002-11/msg00275.html (8,055 bytes)
6. [Amps] LP filter effects (score: 1): Author: wlfuqu00@uky.edu (Bill L. Fuqua); Date: Sat, 16 Nov 2002 14:26:48 -0500; The low pass filter should be placed where the SWR is least. That is before an antenna tuner. High SWR probably burns up more filters than anything else. Also, filters rated for 1000watts (in the old; /archives//html/Amps/2002-11/msg00276.html (10,349 bytes)
7. [Amps] LP filter effects (score: 1): Author: garyschafer@attbi.com (Gary Schafer); Date: Sat, 16 Nov 2002 15:48:20 -0500; A low pass filter does not necessarily have a flat 50 ohm response. Especially when you get to 10 meters. It is already starting to roll off some. This produces some reactance which will show up as a; /archives//html/Amps/2002-11/msg00277.html (9,039 bytes)
8. [Amps] LP filter effects (score: 1): Author: g8gsq@qsl.net (Steve Thompson); Date: Sun, 17 Nov 2002 07:40:43 -0000; to to since I think they don't - I failed to find measurable harmonics when I tried looking, and Peter Chadwick found the same. I think he tested at higher power than the 800W I had. Steve; /archives//html/Amps/2002-11/msg00281.html (8,672 bytes)
9. Fw: [Amps] LP filter effects (score: 1): Author: g8gsq@qsl.net (Steve Thompson); Date: Sun, 17 Nov 2002 08:38:06 -0000; 87A of to filter have more. If we are looking at 100W of harmonic energy in 1500W output power, that's only 12dB down. I'd expect the amp to be a lot cleaner than that. Steve; /archives//html/Amps/2002-11/msg00282.html (8,630 bytes)
10. Fw: [Amps] LP filter effects (score: 1): Author: 2@vc.net (Rich); Date: Sun, 17 Nov 2002 02:05:14 -0800; Amen, Steve - Rich..., 805.386.3734, www.vcnet.com/measures.; /archives//html/Amps/2002-11/msg00283.html (8,793 bytes)
11. Fw: [Amps] LP filter effects (score: 1): Author: wlfuqu00@uky.edu (Bill L. Fuqua); Date: Sun, 17 Nov 2002 11:42:53 -0500; What about a parasitic oscillation? Usually VHF parasitic oscillations are very obvious but if there (for what ever reason) was one that was not as power producing as usual. 73 Bill wa4lav Amen, Stev; /archives//html/Amps/2002-11/msg00291.html (9,391 bytes)
12. [Amps] LP filter effects (score: 1): Author: rakefet@rakefet.com (Vic Rosenthal); Date: Sun, 17 Nov 2002 09:27:44 -0800; I guess it depends on the design of the meter. The old-style 'monimatch' type with parallel conductors definitely did generate harmonics, and was known to cause TVI, hence the suggestion to put it in; /archives//html/Amps/2002-11/msg00292.html (8,476 bytes)
13. [Amps] LP filter effects (score: 1): Author: k7rdx@earthlink.net (k7rdx); Date: Sun, 17 Nov 2002 10:02:36 -0800; Anything between the LPF and ant with ANY amount of corrosive substance (Relay contacts,diode effect, coax switches, poor solder joints,poor station interconnects,etc.) will derate the LPF and make i; /archives//html/Amps/2002-11/msg00293.html (9,396 bytes)
14. [Amps] LP filter effects (score: 1): Author: g8gsq@qsl.net (Steve Thompson); Date: Mon, 18 Nov 2002 11:15:25 +0000; In theory, yes. In practice, it's often difficult to measure anything. Steve; /archives//html/Amps/2002-11/msg00305.html (8,167 bytes)
15. Fw: [Amps] LP filter effects (score: 1): Author: g8gsq@qsl.net (Steve Thompson); Date: Mon, 18 Nov 2002 11:17:28 +0000; I think it would have to be reasonably close to, or lower than, the signal frequency for 100W ish to get through the tank circuit and reach the o/p connector. Steve; /archives//html/Amps/2002-11/msg00306.html (7,733 bytes)

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