Hi Stuart, First you said the cone antenna was 90% efficient and the MFJ loop was 10% efficient on ten meters. Now you say "**some loops** are 10% efficient". Of course that is correct, because some
Hi Paul, The reference standard that makes any sense for measuring transmitter IM is if everyone uses the same reference standard. It really does not matter if it is dB below PEP or dB below one tone
Well, at least it would be good for SSB now. It makes the RX340 about like the old FT101EE's and unmodified Drake R4C's. 73, Tom W8JI W8JI@contesting.com
Hi Carl, I simply made an observation that your -65dB IM3 measurements place that receiver in the close-spaced IM3 performance range of rigs like the FT101EE and unmodified Drake R4C receivers I hav
If we stay away from subjective personal opinions and use measured data to compare performance, most of the problems vanish. Once we get beyond facts and into opinions, much or most of the informati
Perhaps the 9000 amplifier needed some distortion. Many people actually like a little distortion in certain music passages. Liking a certain "sound", however, is nothing like comparing dynamic range
That might indicate someone has a *very* large patio or a very poor calculator. Bandwidth is tied to energy storage in the system. When an antenna is physically small and efficient, energy storage i
Even when tone-deaf, you can still zero beat signals. You might have to "hunt" for the beat a tiny bit more, but it is no problem to find. Like many skills, a little learning and practice will offse
The K2 is mostly an indicator of how careless designers are, rather than how good or special the K2 actually is. It doesn't use any special care, or even special technology, and it equals or beats a
Power foldback is only one small part of the problem caused by a mismatched load. CW may be one issue, but we also should be careful when using loads that are not close to the PA design impedance wh
That didn't come out so clear. What I intended to say was the K2 is not a sophisticated design at all. It uses 1980's or earlier technology in the mixer and garden variety single-ended 2N5109 RF and
That's why I won't buy a DSP based radio. Performance is poor enough using conventional filters because the filter follows too many mixers and semiconductors. Not only that, have a listen to keyclic
The point is DSP filters are so far back in the system, they might as well be at the headphone jack. While I can find many radios that have narrow selectivity after just second mixer, virtually all
What is the close-spaced blocking and IM DR of the receiver? I have a homebrew single-conversion receiver that does over 100dB IM and blocking DR at 1kHz test spacing, how does the RX340 compare to
If I wanted a radar receiver that maps hundreds of echos and measures frequency shift of each echo, I'd expect a complex data storage and signal processing system. If I wanted a receiver that was fr
Except we probably need at least 12 bits of digitized information and a very good low-noise fast A-D convertor to have dynamic range that equals that of a conventional crystal filter. Right now that
Hi Ron and all, I have a slightly different perspective on this. While I agree the best practice is to disconnect antennas, the real secret is in cable routing and grounding, not in lighting suppres
By the way, I don't want selectivity ahead of a mixer...I just don't want it back after passing through 10 stages with semiconductors. Quite often one or more of those additional stages will not be d