Ron, AC7AC wrote: "Someone I was chatting with recently said he had tested the S-meters of several receivers and found that 1 S-unit can equal anything from 3 dB to more than 6 dB. I had always assumed the target was 6 dB/S-unit. Apparently not so." ==========
Years ago, there were two "standards" for S-meters. 1) The Collins standard was 100 uV = S9 and each S-unit was 8 dB. 2) The Hallicrafters standard was 50 uV = S9 and each S-unit was 6 dB. Manufacturers naturally adopted the Hallicrafters standard because the Collins standard resulted in a stingier S-meter (higher S-meter readings = better receiver, right? - No!!!!) It is rare, with the new transceivers currently on the market to find one that strictly adheres to the "standard". Virtually every tranceiver today uses the 50 uV = S9 criterion, but the change per S-unit is much less than 6 dB. This results in a substantial signal such as 1 uV (which should read S3.5 on an accurate S-meter).not even budging the S-meter on most receivers today. In dB above S9, the S-meters most transceivers today seem to be fairly accurate. If all manufacturers complied with the "standard" to the letter, S-meter readings would be more meaningful. As it is now, they are useful only for reference readings such as when someone does an A/B check on his antennas with you. BTW, the values I posted originally were with the receiver preamp turned off in all cases. 73, de Earl, K6SE _______________________________________________ Elecraft mailing list Post to: [email protected] 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
