[Elecraft] spectrogram

[Tom Hammond]

Any time you use an audio-based oscilloscope, monitoring the AF 
output from your receiver, you have to be aware that whatever you see 
on-screen is not only representative of the signal itself BUT to a 
bigger extent it reflects those characteristics placed upon it by the 
receiver itself (it's filters, the AGC characteristics, etc.). As a 
result, you should always remind yourself that what you're looking at 
(if it's coming thru the receiver's audio system) is not necessarily 
what is actually 'on the air'.

73,

Tom Hammond    N0SS

At 11:55 AM 1/22/2006, n3drk wrote:
>Listed below is a link for a Windows based Oscilloscope. This can be 
>used for transmitting but I do not know about receiving. What do you 
>guys think? By  the way thanks to all for responding to my original post.
>
>http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=3428
>
>
>73s
>john-n3drk
>
>
>----- Original Message ----- From: <ab4cz at comcast.net>
>To: "n3drk" <n3drk at triad.rr.com>; "elecraft" <elecraft at mailman.qth.net>
>Sent: Sunday, January 22, 2006 9:31 AM
>Subject: Re: [Elecraft] spectrogram
>
>
>>
>>John,
>>
>>Sjpectrogram is a FFT (Fast Fourier Transform) spectrum analyzer 
>>program. It's display is amplitude versus frequency.  What you need 
>>to display the "Christmas Tree" and CW waveforms is 
>>an  oscilloscope display.  In the case of the Christmas Tree, the 
>>oscilloscope is set up to display RF drive or audio on the 
>>horizontal axis and RF output on the vertical axis (the 
>>oscilloscope is in X-Y mode, with x=drive, Y=RF out).  For the cw 
>>envelope you use the oscilloscope in the conventional mode where 
>>the horizontal axis is time and the vertical axis is voltage.  So 
>>the short answer to your question is "NO".
>>
>>jim, AB4CZ
>>
>>>can Spectrogram also show the
>>>Christmas Tree effect for SSB? How about the rise and fall of the CW note?
>>>What about in receive mode. Can it also show these for the received station?
>
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