In a message dated 5/15/07 7:58:01 PM Eastern Daylight Time, [EMAIL PROTECTED] writes:
> If the day ever comes that we do find ourselves unable to squeeze in > sideways on a band, perhaps we'll need to re-think the use of some wider > bandwidth modes, just like "King Spark" was outlawed for just that reason > about 75 years ago. > > Spark was outlawed for US hams in 1927. Part of the "1929 rules" that came about as a result of a series of World Radio Conferences in the 1920s. But it was a moot point by then. Nobody was still using spark on the ham bands by 1927 - it was simply ineffective compared to the new tube transmitters. Time and time again, it was shown that a 50 watt CW rig could do as well or better than a kilowatt spark on 200 meters, and that was the end of that. When hams went to the short waves, spark did not go with them. If you think we have fast progress and lots of change today, just consider what those hams of the '20s and '30s went through. When hams got back on the air after WW2, 99% were on 200 meters, using spark rigs. The well equipped amateur might have a kilowatt rotary spark, a big Marconi-type antenna (4 wire flat-top 100 feet long, between two 75 foot masts, with an incredible ground system), and possibly a form of regenerative receiver with Audio detector, loose coupler and a stage or two of audio - all battery powered. On a really good winter night, such a setup might be good for 1000 miles. On an average night, 400-500 miles. During the day, maybe 100 miles. Fast forward 5 years or so (1924-25). The oceans have been spanned, using short waves and far less power than it took to work 1000 miles on 200 meters. Tube transmitters are all the rage, while 200 meters is old hat and spark is rapidly disappearing. Superhet receivers are in the hands of a few, bands like 20 meters allow DX in daylight, and there are a few hams using voice. The old flat-top Marconi is gone, replaced by a balanced Hertzian dipole fed with the new "ladder line". Fast forward 5 more years or so (1929-30). The whole world has been worked using short waves, to the point that "DX" has come to mean continents and countries worked, not distance in miles. 200 meters and spark are ancient history. The advanced amateur has a multistage tube transmitter and a superhet receiver. Crystal control is becoming popular. The new 1929 rules require clean, stable signals, so monitors, filters and rectifiers are the order of the day. "AC" tubes are used for the receiver, and there is a considerable selection of new bottles for the transmitter. Some hams are on 10 and even 5 meters. Compare the 1919 shack with the 1929 shack, and almost nothing in the first was used in the second. Even the keys and headphones were usually different. Fast forward 5 more years (1934-35) and the equipment of an advanced ham station could be used today with little or no modification. Single signal superhet receiver, crystal controlled transmitter, T9X stabilized signals, clean Class B plate-modulated 'phone, even SSB. 73 de Jim, N2EY ************************************** See what's free at http://www.aol.com. _______________________________________________ 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
