How do you turn on and off the Crystal filter?
----- Original Message -----
From: "Phil Scovell" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, April 04, 2010 8:42 PM
Subject: Just 20 Hertz Makes The Difference
>I was tuning around on 40 CW a couple of nights ago and heard a guy calling
> CQ. I listened for a couple of minutes until a very weak W8 answered the
> W5
> calling CQ. The W8 wasn't Q5 copy. I like hearing where people are from
> so
> I figured I'd listen long enough just to see where the W5 was from. When
> he
> turned it back to the W8, I heard the W8 say he was QRP. Since I ran QRP
> for 18 months back in 76 and 77, I have a fondness for QRP operators so I
> listened because I wanted to find out how much power the QRP station was
> running. As I said, he wasn't Q5 so I wasn't too sure I could copy well
> enough to hear his power level. Just then, a high speed CW operator in
> Fresno California, who normally works a friend of his in Florida, began
> calling his friend, W4NPX, on 7032.00 which is their main frequency.
> W5WXZ
> is 89 years old and he and W4NPX run anywhere from 40 to 60 WPM when
> talking
> to each other on their CW keyboards. No, they copy by ear and are not
> translating the code by using decoders. W6WXZ was 10 over 9, which wasn't
> unusual, because he always has a good signal into Denver. This put him in
> the center of my band pass CW filter so he sounded extra loud at the time.
> I was listening to the W5 and W8 on 7033.58 and so I decided to see if I
> could filter down on the W8 in order to hear him when he gave his power
> level. I snapped on the additional CW filters, clicked on the tunable
> crystal filters, and dropped the W8 into the notch filter hole created by
> the tunable crystal filtering system on the Icom 7000 radio. The QRP
> station was running now Q5 and was running just 4 watts. Just for the fun
> of it, I zero beateW6WXZ, running along at 50 words per minute, keeping
> the
> W8 within the notch filter range, and then snapped the VF O knob into the
> 4
> position setting which allows each click of the knob to tune 1 Hertz. I
> counted clicks to see just how far off frequency the W6 was running along
> at
> 50 WPM. He was 20 Hertz away and I was still copying the W8, who was
> below
> Q5 copy at first, against the W6 who was 10 over S9 on the meter. I once
> again was amazed at the fine tuning of the Icom 7000. You'd think I'd be
> used to it by now but every time something like this happens, I am amazed.
> In fact, I just tuned on to a huge pile up of U S stations calling a
> Paraguay, ZP5CW, station on 40 CW. The DX station was not Q5 and it was
> made worse since he was running the pile up on frequency and not operating
> split as so many DX stations do when trying to control a big pile up. I
> was
> frustrated because I could not hear the call sign of the DX station. So,
> once again, I cranked down on the DX signal, dropped into the lowest of 3
> CW
> filters, flipped on the tunable crystal filtering and dropped him into the
> hole created by the notch filter, but with all the U S stations on, or
> near,
> his frequency, I still could not get a clear enough signal to pull his
> call
> sign out of the pile. So I snapped on the DSP and there he was. I got
> his
> call in spite of all the U S stations, loud and strong, calling him. I've
> said it before but I have always dreamed of such a CW receiver and now I'm
> using one.
>
> Phil.
> K0NX
>
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