When I compare 2 radios without using proper test equipment, for one thing I consider is the radio's ability to hear the weakest of signals. I use the same antenna and tune one radio for a weak signal and then switch the antenna to the other radio and see how well it receives that same signal. I continue that for some time searching for the weaker signals.
Loudness by itself is not a proper criteria, and often can be misleading - it has too many dependencies, like how much raw audio power is available? how is the AGC activation making a difference? how much noise is present in the receiver? etc. MDS measurements as described in the XG1 manual can be meaningful and do not take a lot of equipment. If the DMM is not capable of displaying a low audio output level, a 'scope can be used in place of the DMM to measure the AF voltage and give meaningful results. 73, Don W3FPR -------------------- That's a game I like to play with my homebrew receivers too. As a tinkerer/builder, one reason I like to have a 'state-of-the-art' rig on hand is to use it for making comparisons in actual on-air use to various homebrew projects. I have a regenerative receiver using only two tubes and a handful of parts that is just as sensitive as my K2, within the range of my ability to hear. That is, if I find a signal that's a whisper on the noise in the K2, it's there with the regen too! Does that mean the regen is as good as the K2? Far from it! Just let the band get a bit crowded and the regen collapses. Regenerative detectors are amazingly sensitive, but have a very limited dynamic range and, at best, fair selectivity. When I used to service radio consoles on large ships, it was common for the backup receiver for 'Sparks' to be a regenerative receiver. The main receiver was a modern superhet, but the backup kept in case the main receiver failed in the middle of an emergency was whatever the receiver the new main had replaced. One time I returned a regenerative receiver I had taken to the shop to fix and, after installing it in the CW console while Sparks looked on, I turned it on. The speaker erupted with a cacophony of overload QRM from all the high-power broadcast stations surrounding us on the San Francisco Bay. I commented to Sparks that the receiver was working properly but they aren't any good in that sort of large-signal environment. I think Sparks was as old as the receiver. He cast one baleful eye on my and said, "Sonny, if this tub's a-sinkin' out there and some guy is so strong he's block'n my regen, he's the first one I WANT to talk to!" 'nuf said! What constitutes the best performance depends upon where and how it's used. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
