The subject of 'Broadband in Gas' technology, which I brought to readers' attention in July, resulted in a number of questions. Vic Ludlow, G3JLZ, was "bemused by the idea of high-capacity (not broadband) Internet signals being propagated either within the gas in alkathene gas pipes, or perhaps being launched along a waveguide formed by a metal gas pipe". As he explained, "I taught waveguide theory and applications for some years - I can't see an ad hoc arrangement of copper piping and assorted joints working at all well -think of the standing waves and the losses!" I agree wholeheartedly, but clearly this technology does not rely on the usual desire of trying to deliver the maximum amount of RF at the far end of the waveguide. If I was to put 1W into a waveguide that was going to feed a dish but only managed to deliver 1 μW at the other end, I'd be far from satisfied with the results, but here we are not talking about feeding an antenna, just a detector in the pipe itself. If 1W was go in and 1 μW arrive at the far end (a 60dB loss), that could be enough for the system to operate.
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