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CW rise time
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Mark_WS7M
Member ✭✭✭
Found a very old post about CW rise times and wonder what they are set to now.
I am getting reports of keyclicks when using my SPE amp.
I am getting reports of keyclicks when using my SPE amp.
0
Answers
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Normally, with an amp, that is not enough delay.
Listen to your signal on a dummy load and increase delay until it stops the clicks.0 -
Delay is related to rise time how?0
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If the amplifier does not switch into transmit quickly enough, it will "hot switch", resulting in clipping off the leading edge of the carefully shaped CW signal from the Flex. Result: terrible key clicks.
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So what delay are you guys running?
There are two:
1) TX delay at the phone plugs or acc plug. I run that at 20
2) The CW hang time which I have tried from 25 up to 1000.
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It is the TX delay for this test. The ones I use are (much) older QRO brand using a vacuum relay and the delay is higher than 20. I have no experience with a SPE. I have a 6700 so just put the second RX on a dummy load and start adjusting the timing until quiet - probably around 25-30ms0
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Set CW raise time to 6 ms. 4 ms is borderline and 2 ms is a definite nightmare for the others.0
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Where are you setting CW rise time?0
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Inquiring minds want to know... (me included)0
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Guess we will never find out...0
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I won't hold my breath!0
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Seems like a simple question? Either you can adjust or you cant????0
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Rise time is not adjustable in the Flex. Looking at the QST review, I seem to remember it was around 5 ms which is the textbook sweet spot. The shaping is very good so the barefoot Flex is not likely to generate bad clicks. I will have to look at the band using full duplex to see how wide my 6400 keying is. The higher the keying speed, the wider it will be. 73, Len, KD0RC0
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