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Dale Parfitt schrieb:
Cool, that beats my picking up 50 kw Radio Orbita 3 from Russia or the African channels (Botswana and Nigeria) booming last night. Not bad for a sony 7600GR portable eh? I figured out the image problem. I think it's the voltage limiting diodes I place yesterday across my antenna input to ground. That is exactly what it is assuming yor RX uses a 455 kHz IF. Which, btw, it does. And it doesn't have too great an image rejection either (~40 dB). When using a big antenna with a 7600G(R), I'd advise a passive preselector / antenna tuner, not only for better image rejection but also against IM products (here in Central Europe signals are strong enough to produce IM products on the whip alone). It's a lot of receiver for the money, but in no way an AR7030+... (Except for AM demodulation, that is - this sounds rather crappy and distorted on the AOR, but that's what the excellent synch is for.) Stephan -- Home: http://stephan.win31.de/ | Webm.: http://www.i24.com/ PC#6: i440LX, 2xCel300A, 448 MB, 18 GB, ATI AGP 32 MB, 110W This is a SCSI-inside, Legacy-plus, TCPA-free computer ![]() Reply to newsgroup only. | See home page for working e-mail address. |
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On Wed, 24 Sep 2003 15:47:10 +0200, Stephan Grossklass
wrote: Dale Parfitt schrieb: Cool, that beats my picking up 50 kw Radio Orbita 3 from Russia or the African channels (Botswana and Nigeria) booming last night. Not bad for a sony 7600GR portable eh? I figured out the image problem. I think it's the voltage limiting diodes I place yesterday across my antenna input to ground. That is exactly what it is assuming yor RX uses a 455 kHz IF. Which, btw, it does. And it doesn't have too great an image rejection either (~40 dB). When using a big antenna with a 7600G(R), I'd advise a passive preselector / antenna tuner, not only for better image rejection but also against IM products (here in Central Europe signals are strong enough to produce IM products on the whip alone). It's a lot of receiver for the money, but in no way an AR7030+... (Except for AM demodulation, that is - this sounds rather crappy and distorted on the AOR, but that's what the excellent synch is for.) Stephan Hmmm...guess the diodes are not such a hot idea after all. Easy enough to desolder and remove them. That would leave my 2.2k ohm resistor as a bleed off inside my antenna tuner. I will order a gas arc breakdown tube for major voltage impulses and be done with it. Or alternately, should I run into a pile of cash sometime soon, buy an ICE model 197 RF limiter/arrester. mike |
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