[TenTec] Orion 565 Key clicks (Karl Seper)
floyd at k8ac.net
Mon Jul 25 10:46:27 PDT 2011
I've worked on a couple of non-Ten Tec rigs to eliminate or reduce the
key click problem. Forget about the unmodulated noise you're hearing
for now - perhaps just phase noise on the signal. If you have clicks,
they will be clearly audible as clicks and you'll hear them at a
reducing intensity as you tune off the signal. You may hear them a
couple of KHz away. I suggest doing your testing at full output power.
I found it difficult to analyze the waveforms while trying to maintain
sync - maybe a storage scope would have made things easier, but don't
have access to one of those. I ended up monitoring the keying using a
second receiver, listening to the audio at a beat note of around 800 Hz
and feeding the audio to the PC sound card line input. I recorded the
audio in the PC and then played it back using an audio editing program
(I used Adobe Audition, but any editor should suffice). It took a bit
of experimenting with the second receiver audio and RF gain level and I
turned off the receiver AGC. The end result was a set of excellent
waveforms that I could zoom in on and analyze for possible click
causes. The editing programs have extremely accurate time scales
allowing you to see the rise and fall times as well as any overshoot on
the rise. You'll hear clicks if the rise and/or fall times are too
short, if there is a sharp shoulder on either one, or if there is any
overshoot on the rise. Suggested rise/fall times are well documented
elsewhere, and the rest is common sense. If you see any sharp corners,
spikes, etc., chances are excellent that clicks will result.
If you monitor your Orion that way, you'll clearly see the effect of
varying the rise/fall times through the CW menu parameter. I sold my
FTDX-5000 due to unresolvable keying problems that I verified using this
technique. When I acquired the Orion II shortly after that, I ran it
through the tests and was amazed at how nice the waveforms looked and
how they changed as expected when I varied the menu parameter. I made
one interesting discovery regarding the Orion II keying however - with
the CW weighting set to 100% the dot to space ratio was nowhere close to
the 1:1 it should have been. A setting of around 85% provided the right
73, Floyd - K8AC
On 7/25/2011 10:17 AM, karl.seper at amway.com wrote:
> Yesterday while hunting for ST0R, a friend and fellow DX'er that lives
> about a mile away communicated to me that I had Key Clicks in my Orion (I
> was running barefoot at the time). I stopped transmitting and started to
> check it out.
> 1. Hooked up an o-scope to look at the keying waveform - looked ok to my
> untrained eyes.
> 2. Listened on another receiver (that I disconnected the antenna from)
> (running 5W now) and yes up to 5 KHz above and below the passband I heard
> unmodulated noise. Center of passband sounded ok.
> 3. Checked PS voltage under load - and found that it was>13.5V.
> 4. Checked all power connections - all ok.
> 5. Set the CW rise time to 10ms - no improvement
> A few other tidbits that may or not be related.
> 1. Also, since I purchased this radio used, the data communication to the
> N1MM or DX LabSuite Commander does not begin until after the rig is on for
> about 5 minutes or so - almost like not enough voltage on the RS-232.
> 2. The LED's at the analog meter are very dim, sometimes come up to normal
> brightness, but unpredicatble,
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> TenTec at contesting.com
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