The recent discussions concerning abilities of Orion in QRQ have sparked my
interest and have prompted me to conduct a few tests. For those that are
interested I set out my findings here.
Firstly, let me point out that except when contesting all my CW is sent
using a paddle and almost never at speeds above 45 wpm. As a consequence I
have found no problem with Orion in my daily use.
The tests carried out here used CW generated by computer running Writelog.
Weighting was set to a standard 50%. In all cases, Orion with rise/fall set
to 3mS transmitted into a dummy load. The signal generated was monitored on
a Kenwood TS570, which was at hand and was recorded to a .wav file using
WavePad. The recordings of high speed transmissions were critically
reviewed at a reduced speed.
My first tests were conducted Wednesday when I set sending speed to 60 wpm.
The recorded transmission was speed reduced 50% and reviewed. Code timing
appeared good and there were no missed elements. Yesterday I had a request
from Toby, W4CAK to share the 60 wpm .wav file together with the speed
reduced version of it. Toby agreed the code sounded good and enquired what
70 wpm would be like.
This morning I set out to answer Toby's question and had some very peculiar
results. I used the same set up but set Writelog to produce 70 wpm 50%
weighted code. I recorded the transmission and noticed that I couldn't read
it. I halved the speed of the .wav file recording and found it was still
unreadable. Next I decided to check out 65 wpm, this was unreadable too. I
went to 60 wpm, also unreadable. I continued reducing speed and found the
code started to improve but it was not back to a good quality until I got
down to 45 wpm. At this stage I was puzzled, as 60 wpm had been absolutely
fine 2 days ago with the same Orion and exactly the same set up. I could
only figure two factors which were different this time around. The first is
that I had just switched the Orion on where it had been on for sometime on
Wednesday. The second is that on this occasion I was reducing speed from a
point where the code was unreadable rather than increasing it from a point
where it was good. I have no idea why either of these factors might be
relevant but they are the only differences I can identify.
I went for a coffee and decided I would retest starting at 40 wpm and
incrementing in 5 wpm increments to 70 wpm. I did this and found that the
code was good up to 60 wpm. At 65 wpm odd character elements were dropped
altogether or truncated. At 70 wpm the code was unreadable.
I increased the speed to 80 wpm for good measure. The code was absolutely
unreadable.
Next, I reset the speed to 70 wpm and made .wav file recordings at that
speed and in decrements down to 40 wpm. At 70 wpm the code was unreadable
as before. At 65 wpm there were character elements dropped or truncated.
At 60 wpm and less the code was good.
Why when Orion had just been turned on, the code generated at speeds as low
as 50 wpm was bad, I really have no idea. Orion having been on for an hour
or two, I have re-run my tests several times and at 60 wpm the code is
consistently good while at 65 wpm elements are dropped and 70 wpm the code
is completely unreadable.
Bob, 5B4AGN
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