tag:blogger.com,1999:blog-1146246558798303856.post1688458256996110057..comments2024-03-25T11:45:15.794-04:00Comments on Ham Radio - QRP: Finer than a frog's hair split twiceAA4OOhttp://www.blogger.com/profile/08437750216586991500noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-1146246558798303856.post-89736007817758631262016-01-08T16:46:50.231-05:002016-01-08T16:46:50.231-05:00Update: I modified the pitch of the sidetone on t...Update: I modified the pitch of the sidetone on the Ten-Tec C21 to be in the bandpass range of the received CW signals so I no longer have to use the external sidetone from my Ham Keyer to hear myself when I use the AF1 in its narrowest filter position.AA4OOhttps://www.blogger.com/profile/08437750216586991500noreply@blogger.comtag:blogger.com,1999:blog-1146246558798303856.post-55076869421013817332016-01-05T17:22:31.543-05:002016-01-05T17:22:31.543-05:00Thanks Paul. I've been using it pretty regula...Thanks Paul. I've been using it pretty regular with the Ten-Tec and the only issue is that my TT-C21 has a fixed sidetone pitch that's quite low (maybe 500 Hz) but the audio passband on the TT pre-amp board is optimized for 750 Hz so when I engage the AF1 filter it is quite effective and completely obliterates my sidetone :)<br /><br />I'm looking at a modification to raise the fixed pitch of the sidetone to 750 Hz, in the meantime I am operating using my external ham keyer as my sidetone monitor. Unfortunately it's not in my headphone audio so I leave my headphones a bit askew when I'm sending in order to hear the sidetone now. <br /><br />All-in-all the AF1 is doing a spectacular job for the old radio and once I figure out how to modify the pitch of the TT-C21 sidetone to the same pitch as its expected passband I'll be in vintage rig nirvana.AA4OOhttps://www.blogger.com/profile/08437750216586991500noreply@blogger.comtag:blogger.com,1999:blog-1146246558798303856.post-78746705948786050662015-12-31T22:22:47.923-05:002015-12-31T22:22:47.923-05:00Very informative article on the AF-1, Richard. Th...Very informative article on the AF-1, Richard. Thanks for including the video, which enables us to hear the audio filtering at work. Looks like an ideal companion to your Century 21. 72, Paul AA4XXAnonymoushttps://www.blogger.com/profile/09277098100088730954noreply@blogger.comtag:blogger.com,1999:blog-1146246558798303856.post-28795518536011422242015-12-29T13:10:33.044-05:002015-12-29T13:10:33.044-05:00This might be a good addition to any of the QRP tr...This might be a good addition to any of the QRP transceivers, especially when people make customized go boxes etc.Davehttps://www.blogger.com/profile/01202457666219954498noreply@blogger.com