I use digipan to check frequency and on my new computer it is right on.
On another computer with a old sound card it is off as much as 10 Hz.
My transceiver is a Pegasus and I have a MFJ -886 frequency counter.
Best regards, Jim FitzSimons W7ANF
-----Original Message-----
From: George , W5YR <w5yr@att.net>
To: Jan Ditzian <ditzian@alltel.net>
Cc: tentec@contesting.com <tentec@contesting.com>
To: <tentec@contesting.com>
Date: Saturday, July 08, 2000 3:32 PM
Subject: Re: [TenTec] OMNI VI+ Frequency Drift
>
>Jan, I use Zakanaka exactly the same way as you described for DigiPan to
>evaluate frequency error in the calibration of my Kachina radio.
>
>If you are seeing a different result with the two programs, first try
>using them the same way and compare results. That is, use both reading
>audio frequency not direct radio frequency.
>
>If there is still a difference, then tune in WWV on AM and measure the
>modulation frequency which will be spot on regardless of receiver
>calibration. If WWV is on with 600 Hz tone and you measure 598.4 Hz with
>either program set to show Audio Frequency, then your soundcard is off by
>1.6 Hz. Neither Zaka nor DigiPan allow for "tuning" the soundcard the way
>the original PSK31 program did, so just use that figure as an error
>correction when measuring the offset carrier frequency at 9,999.000 Mhz.
>
>On my Kachina, the soundcard reads spot on with either program. The
>computer stays on 24/7, BTW. The WWV calibration is seldom more than two
>Hz in error and frequently is less. That is with the radio on 24/7 and
>well warmed up and stabilized. From a cold start, it will be within 5 or
>6 Hz and settle to 2 Hz or less in about 30 minutes.
>
>The least significant tuning step in one Hz, so it is easy to dial in the
>correction to the nearest Hz when getting on an exact frequency is
>important, which it very seldom is.
>
>
>The Kachina firmware also implements an automatic calibration to any
>specified input r-f frequency. The result of that process, which can
>greatly shorten the settling down time, is usually an error of about 3 Hz
>or less.
>
>Another quick frequency cal error check is to use CW and tune in the WWV
>carrier on say 10 MHz. If everything is aligned properly, the audio tone
>should be on say 700 Hz or whatever the CW offset is. On the Kachina it
>is software selectable from 300 to 900 Hz in 100-Hz steps. Again, measure
>the resulting offset frequency and any error will represent the total
>calibration error of both the frequency-determining elements and the CW
>offset oscillator.
>
>The Kachina sports a spotting tone when in CW which is software
>constructed to be precisely on the offset frequency. Thus, with WWV tuned
>in on CW mode, merely pressing the Space Bar generates the spotting tone
>which will beat with the WWV-derived signal tone. Zero beat means that
>everything is lined up with zero error. When the other methods indicate a
>2 or 3 Hz error, this method clearly shows the same as a beat of 2 or 3
>Hz - very easy to hear and count, like a piano tuner.
>
>I describe these steps in terms of the Kachina since I do not know to
>what extent the same things can be done, or how, with the Omni and other
>more conventional rigs. Don't fuss at me for taking bandwidth on the
>TenTec reflector to extoll Kachina merits . . . ;^)
>
>The many features of Zakanaka have finally weaned me from DigiPan! I am
>really enjoying using it and highly recommend it for PSK31 operation.
>Having been on PSK since February of 1999 I have had a chance to try all
>the programs that have come out, and Zaka is king of the hill for now!
--
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