[Elecraft] Using an oscilloscope to align a K2

[Don Wilhelm]

Robin,

The time base setting to use depends on what you want to observe.  If all
you are interested in is an envelope display so you can see the amplitude,
slow the sweep down until you can no longer see the waveform detail and make
your adjustments.  Used in this manner, the 'scope is being used just like a
fast responding analog voltmeter.  That is the usual way one would use a
'scope when adjusting the bandpass filters.

Feed the antenna connection with a signal at the frequency of interest and
attach the 'scope probe somewhere in the IF of the receiver (whereever
produces sufficient amplitude for your 'scope - pin 1 of U11 would be a good
place).  If your 'scope does not have sufficient sensitivity when connected
at the IF, you can connect it at the speaker terminals for doing this type
of adjustment - it just isn't critical - do use a good probe, like one of
the X10 low capacity probes to keep from loading the circuits.  If you do
not have such a probe, connect only to low impedance points of the device
under test.  The K2 speaker line is a low impedance point.

You can even use a wideband noise generator at the antenna instead of the
single signal because the range of the bandpass adjustment for the K2 is
limited, it is quite unlikely that you can align to an incorrect peak.

OTOH, if you want to observe the actual waveform of the signal, you will
have to adjust the time base to display the number of cycles that you want
to see.   You can use the 'scope to determine the frequency of a waveform
too, but that requires a well calibrated time base display.

73,
Don W3FPR
----- Original Message -----
From: "RK" <oz6abm@qsl.net>
To: <elecraft@mailman.qth.net>
Sent: Sunday, December 21, 2003 8:45 AM
Subject: [Elecraft] Using an oscilloscope to align a K2


Hi,

On page 72 of the K2 user manual it says that you can use an oscilloscope to
align the 40m bandpass filters.

I wonder if anyone can give me an idea of what settings the scope should be
set to, especially ther time/div ?

Also, can a scope be used to align the Rcv end?

I haven't tried this yet, but I have a PM3256.

thanks and 73
Robin
OZ6ABM

--- StripMime Report -- processed MIME parts ---
multipart/alternative
  text/plain (text body -- kept)
  text/html
The reason this message is shown is because the post was in HTML
or had an attachment.  Attachments are not allowed.  To learn how
to post in Plain-Text go to: http://www.expita.com/nomime.html  ---
_______________________________________________
Elecraft mailing list: Elecraft@mailman.qth.net
You must be subscribed to post to the list.
To subscribe or unsubscribe see:
http://mailman.qth.net/mailman/listinfo/elecraft
Elecraft Web Page: http://www.elecraft.com
Also see: http://www.elecraft.com/elecraft_list_guidelines.htm