[ARC5] CW/MCW

[Richard Knoppow]

-----Original Message-----
>From: Robert Nickels <ranickel at comcast.net>
>Sent: Nov 11, 2013 2:03 PM
>To: arc5 at mailman.qth.net
>Subject: Re: [ARC5] CW/MCW
>
>On 11/11/2013 3:11 PM, Richard Knoppow wrote:
>> The filter people are thinking of was used with aircraft radio range stations.
>
>A few years ago when I was researching the Heath HT-4 light aircraft 
>transmitter, I came across this excellent video showing a modern-day 
>reconstruction of a four-course radio range:
>
>http://www.youtube.com/watch?v=p-VqtNY8vpw
>
>Of course all the original ranges are long gone, so this is really the 
>only chance many of us will have to see and hear what it was like and 
>how it worked.    The value of these filters will be easily apparent 
>;-)   This model radio range operates on 28 MHz.
>
>Sorry for the redundancy to those who are already aware of this video, 
>but I thought it was worth passing along again.
>
>73, Bob W9RAN

    A google search for Adcock radio range will find a lot of stuff on the old range stations.  They were really very clever but had problems due to skywave and the difficulty in determining exactly which beam one was on.  Some stations had additional VHF markers to identify courses.  Also, there was no signal directly over the station, this was called the zone of silence and eventually another VHF marker was added to identify it.  Without the marker a pilot might think he was directly over the station when actually he was in some dead spot.  Courses became reciprocal when passing the station but in bad weather it might be difficult to determine that.