Re: [AMRadio] AM Power Level
Hi Joe, Generally for 100% positive modulation, 1500W PEP translates into a 375Watt carrier. (These are output levels.) But in the real work=ld, this ain't necessarily so... Check WA5BXO's website, there is some interesting reading on AM power regarding carrier and modulation vs. PEP. http://www.qsl.net/wa5bxo/ In particular on John's WA5BXO site, check AM Tech Page, Natural Asymmetrical Modulation, and Amplitude Modulation and PEP. Bacon, WA3WDR - Original Message - From: [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Sunday, May 18, 2003 1:14 PM Subject: [AMRadio] AM Power Level I'm a new subscriber to the list, and I have not discovered the way to do a search through the old archives. Forgive me if this has already been covered. I'm currently in the process of collecting the parts to build a Class-E Am transmitter and Class-H modulator for 75 meters. (I was quite surprised at the relative simplicity of the circuit!) While I have been a boatanchor collector for years, and also an on-and-off-again Electric radio subscriber (though I have every issue) I have never yet been on the air in AM mode. Listening on 75 off and on over the years has me itching to finally change that. I'm interested to know if I understand the newer FCC power guidelines correctly and how peak power on AM is measured. The FCC now stipulates 1500 watts peak output. Am I correct in understanding that in AM, the peak output at 100% modulation is four times the carrier level? Does this mean that if one is to be strictly within the FCC rules, you can have a carrier of only 375 watts in the AM mode? My proposed transmitter will be capable of a unmodulated 600 watt carrier. Fortunately, it appears to be a simple matter to reduce power in a Class-E amp just by lowering the supply / modulation voltage to the MOSFET drains. Any help in furthering my understanding is appreciated. Thanks! 73, Joe N6DGY ___ AMRadio mailing list AMRadio@mailman.qth.net http://mailman.qth.net/mailman/listinfo/amradio
Re: [AMRadio] Camp X Field Day
Hi Matthew, Does your group have plans to include a vintage, 40's era set-up at the site, as well as the more modern gear...? A receiver like the RCA AR-88 comes to mind, which WAS, indeed, used in the original Camp X radio room (condfirmed by photos in the lobby of Lear Seating, which is presently located nearby). ~73!~ Eddy VE3CUI - VE3XZ - Original Message - From: VE3ZQW-Matthew [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Tuesday, May 13, 2003 11:39 PM Subject: [AMRadio] Camp X Field Day On the weekend of June 7-8 the Camp X Historical Society (www.campxhistoricalsociety.ca) with the radio amateurs of the Durham Region will be doing their annual radio re-activation of the former Spy training and SIGINT operation known as Camp X. Operation will be on all HF bands with all modes planned. Callsign for the event will be VE3SCX. Frequencies will depend on conditions at the time. Camp X, located outside of Toronto, was in operation from 1941 til 1969 teaching the art of intelligence, sabotage while operation as a relay station between Great Britain, Canada, and the USA. Next year our group will be building a museum to pay tribute to these secret warriors. Many thanks and 73's Matthew Batten-VE3ZQW President-CXHS [EMAIL PROTECTED] --- StripMime Report -- processed MIME parts --- multipart/alternative text/plain (text body -- kept) text/html The reason this message is shown is because the post was in HTML or had an attachment. Attachments are not allowed. To learn how to post in Plain-Text go to: http://www.expita.com/nomime.html --- ___ AMRadio mailing list AMRadio@mailman.qth.net http://mailman.qth.net/mailman/listinfo/amradio
RE: [AMRadio] AM Power Level
Thanks all for your help. There are far more variables than I thought in calculating the actual PEP output of an AM transmitter. It will be some time yet till I'm ready to get on the air in AM mode. Besides the class-E project, I need to give my Hallicrafters SX-117 receiver an alignment. It's become somewhat deaf over the years. Otherwise, I do not currently have another HF receiver suitable for AM. My older Kenwood transceiver is good for CW and SSB only. Thanks for the help! 73 Joe Bento N6DGY Pleasant Grove, Utah
