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Author Topic: Alternative ways to send code...  (Read 728 times)
W8BBS
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« on: April 27, 2003, 12:07:35 PM »

I just got my first ticket last Augest. I'm an extra, but I haven't even got an HF rig yet. I do want to try CW. It seems there are several ways to send code, the straight key, the iambic, and the 'cheater' ways using a PC keyboard. With software, one could send and receive CW without knowing anyting about CW. This seems to miss the point of CW. The iambic keyers are also cheating in a way, but because it's an old method, and takes skill, it seems to be accepted.

I want to be able to send good code without "cheating". I've been practicing with a J38, and I'm getting better. I've only used a key for a short time. However, I've played the harmonica for over 40 years, and I can make some pretty good sounding code with it. I use a very small harmonica, which I hold in my mouth without using my hands, and I use my tongue. I suppose one could send code vocally as well, just say 'beep beep..." To use a mouth based system of generating code, one would need some kind of filter to eliminate the harmonics, and create a pure tone, but this doesn't seem like it would be a major difficulty.

Has anyone heard of anything similar being used? I'm sure I'm not the first person to think of it.

thanks and 73s,
bruce
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N8UZE
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« Reply #1 on: April 27, 2003, 02:12:21 PM »

What you are describing is known as Modulated CW (MCW).  You feed it in through the microphone jack while the radio generates a continuous carrier.  It is only allowed on the VHF bands and higher (i.e. 6 meters and up).  On HF (160 meters through 10 meters), MCW is not allowed. It has to be standard CW (i.e. on/off keying of the carrier).
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KA8VIT
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« Reply #2 on: May 01, 2003, 02:49:30 PM »

I haven't seen a CW reader yet that does any good unless the signal you're trying to copy is strong, clear with no near-by stations or QRM.

The best CW decoder I have seen is your ear and brain.

73,

Bill  KA8VIT

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WA4DOU
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« Reply #3 on: May 10, 2003, 09:42:30 PM »

If I remember correctly the SB-33 and SB-34 transceivers ,made by Sideband Engineers in the '60's and maybe early '70's used this method of cw generation. It is not MCW. A ssb rig with excellent carrier suppression transmits nothing when no modulation is applied. If you inject a pure tone of say 1000 hz. into the mic. connector and key it, it becomes the defacto carrier and no one knows that it is offset from where the carrier in your rig is generated. There is no way to detect that it isn't accomplished the same way that ordinary carriers are generated if the tone is pure and being amplified without appreciable distortion and assuming excellent carrier suppression.
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K4AO
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« Reply #4 on: May 11, 2003, 03:35:31 PM »

For someone who is learning to use the code, the best device to use first is a straight key. To send good code you have to know what the letters are supposed to sound like and that is best learned on a straight key.

A good operator can normally send decent sounding code between 15 and 20 wpm with a straight key. When your speed reaches that point, you can try a different type of keyer.

By the way, there are a few high speed cw operators who will take exception to your comments about a keyboard being a "cheater" sending device.

73, K4AO
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VA7DAV
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« Reply #5 on: May 23, 2003, 10:48:39 PM »

Rather than trying to filter a complex audio signal down to a 1kHz tone (nearly impossible!) I suggest you think about building a "vox" keyer.  You could have an oscillator that only gets switched on when a certain pre-set level is input to a microphone.
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