One of my neighbor hams had a 75A4 when I was in high school - no later than 1957.
Dunc, W5DC Joe Subich, W4TV wrote: > >> Drake?? What about Collins and the 75A4 that had a fine shift >> control on the front panel, done mechanically/electrically >> but was well before Drake had a radio.. Width was controlled >> by filters. >> > > I don't know when the 75A4 was introduced but the shift control > was present on the Drake 2B, probably the 2A and maybe even > the 1A. In any case, independent shift and width controls > certainly go back into the 60's if not earlier ... long before > high cut and low cut were mis-identified as shift and width. > > 73, > > ... Joe, W4TV > > > > > > >> -----Original Message----- >> From: Merv Schweigert [mailto:k...@flex.com] >> Sent: Tuesday, December 29, 2009 8:22 PM >> To: li...@subich.com >> Cc: 'Elecraft Reflector' >> Subject: Re: [Elecraft] Filters for K3 >> >> >> Drake?? What about Collins and the 75A4 that had a fine shift >> control on the front panel, done mechanically/electrically >> but was well before Drake had a radio.. Width was controlled >> by filters. >> Merv KH7C >> >> >> Originally, IF shift was defined as moving one IF passband >> within another IF passband, making the resulting passband the >> intersection (not the union) of the two passbands. >> >> >> Again, you are incorrect. Drake implemented a shift control long >> before any of the Japanese imports and its shift moved the entire >> passband without changing the width. Width was controlled >> separately, in discrete steps. >> >> Many of Yaesu's transceivers ... going back to the 1970's ... >> also had independent shift and width controls. Even today >> the FT-1000D, FT-1000MP, Mark V, FT-2000, FT-9000, etc. have >> width and shift controls that are independent and behave >> exactly like the K3 in Width/shift mode. >> >> It was only when Kenwood eliminated the third filter and >> failed to link the mixers that shift/width became effectively >> a high cut or low cut filter. >> >> Like so many other features of the radio, what you prefer >> depends on what you first used. For me, the current Elecraft >> design is the right way to do shift and width. Even better, >> I can select independent shift and width for CW and digital >> operation or high/low cut for SSB operation at the press of >> the encoder (or if I select 10 Hz steps for shift the behavior >> can change automatically as I change between voice and CW/data >> modes). >> >> 73, >> >> ... Joe, W4TV >> >> >> >> >> >> -----Original Message----- >> From: elecraft-boun...@mailman.qth.net >> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Al Lorona >> Sent: Tuesday, December 29, 2009 6:18 PM >> To: Elecraft Reflector >> Subject: Re: [Elecraft] Filters for K3 >> >> >> >> It depends entirely on which brand of radio you were using >> and how the manufacturer implemented IF shift and/or width. >> >> Originally, IF shift was defined as moving one IF passband >> within another IF passband, making the resulting passband the >> intersection (not the union) of the two passbands. >> >> When you do that, you effectively reduce the width *and* the >> center frequency of the IF passband... it has nothing to do >> with manufacturers failing to make it work correctly. >> >> Take two pieces of paper and cut a square in each. Hold them >> up to a window, and slide one square horizontally across the >> other one, and note how the width *and* center of the opening >> shifts left or right. This is what I mean when I say, "IF >> shift". We might be talking about two different things. >> >> Regards, >> >> Al W6LX ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> >> >> >> > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
