Peter...no, you dont have a problem. The Corsair II and older TenTec rigs have
an awful sidetone. It is generated by a UniJunction Transistor (UJT) and the
'tone' created is close to a square wave, which is why it sounds so horrible. I
have been able to 'fix' that by removing one of the resistors in the resistive
'pad' between the UJT and the op amp, and adding a simple audio filter in that
resistors place. Of course a square wave is the fundamental oscillating
frequency and ALL of it's harmonics. By running a square wave through an audio
filter, at the oscillators fundamental frequency, you can eliminate most of the
harmonics; what comes out of the audio filter is a much cleaner and much better
sounding sidetone.
At 05:14 PM 9/13/97 +0100, you wrote:
>>you must very carefully get
>>the CW xtal filter to center at 750 Hz also, by centering
>>the PBT at the top and making sure the beat note is right
>>(you can check by comparing it with the sidetone I think).
>
>The sidetone on my Corsair II (which I've had for a few months now -
>it's my first TT rig, and one with which I am delighted) is *not* a
>particularly clean tone. I would find it hard to match the pitch of
>an incoming signal to it.
>
>Does this mean my rig has a problem (with the sidetone), or is this
>simply 'how it is'?
>
>PS Don't forget, the sidetone pitch is variable, and therefore may not
>be adjusted close to 750Hz.
>--
>72/73, Peter G3XJS ( http://www.barville.demon.co.uk/qrpinfo.htm )
>
>--
>FAQ on WWW: http://www.contesting.com/tentecfaq.htm
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>
Chester Alderman
<color><param>0000,0000,ffff</param>W4BQF -- Tom
</color><color><param>ffff,0000,0000</param>chestert@pressroom.com
</color>
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Administrative requests: tentec-REQUEST@contesting.com
Problems: owner-tentec@contesting.com
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