I have a problem with the sidetone o/p from my TiCK keyer.
The sidetone o/p stays high (+5V) in between character elements during
TX keying. In command mode this is not the case, but the quiescent
level is 0V instead.
When mixing the attenuated keyer tone into the audio circuit of the
rig, the DC level changes cause a very annoying clicking and a
momentary large disturbance of the DC bias of the audio amp (hence a
nasty momentary distortion).
If instead I use a piezo beeper, it will emit a continuous tone which
is modulated with the 620 Hz during key down. Not very nice...
The only way out of this seems to be a piezo transducer that doesn't
beep of its own. However, these commonly have resonant frequencies of
several kHz and will not have much output at 620 Hz.
Obviously there must be some kind of transducer that will output an
clearly audible signal at 620 Hz, but what type would that be? Where
to find such a special critter at a total cost not multiplying the
admittedly moderate cost of the keyer IC and PCB several times? (I
bought my TiCK IC's last summer.)
I wonder if this is about making a seemingly simple thing pretty darn
difficult? The fact that in command mode there is no 5V level in
between character elements (heard it and seen it on a 'scope) would
prove that at least that can be done. If furthermore the tone o/p
would go high impedance instead of to either 0 or 5 V between elements
the tone could be mixed with the rig's audio. Then no piezo beeping,
which would very clearly contribute to the peace in this family.
BTW, one of the considerations in me learning CW was to not having to
talk out loud at night and whenever else. A nasty beeping sound for
keyer commands is a no, no really.
How have you interfaced your TiCK to your rig? I'd like to know,
because I'm in a fix here.
tnx es 73, oh2zaz
Arjen Raateland
--... ...-- -.. . --- .... ..--- --.. .- --..
Finnish Environment Institute, Helsinki, Finland
SAS Support
EMAIL: Arjen.Raateland@vyh.fi
tel. +358 9 4030 0457
fax +358 9 4030 0490
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