Colin,
That only works if one side of the meter operates at ground potential, but
not of both sides of the meter are above ground, which is usually the case.
Besides, I don't think you want voltage from the key circuit on the same
jack as your oscillator because of stray capacitance that might be
introduced in the jack.
Steve
----- Original Message -----
From: "Colin McDonald" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, March 18, 2008 10:18
Subject: Re: tone oscillator.
> that could work yep.
> I think the straight key jack is a regular phone jack, meaning it has just
> the tip and sleeve connections.
> If a person were to replace that jack with a TRS jack, with the extra ring
> connection, you could easily use the sleeve and ring for the tone
> oscillator
> and allow the sleeve and tip to remain the CW key circuit.
> I think the use of a diode in either the tone oscillator circuit or the cw
> key circuit to prevent any ground loops might be wize as well.
> Though i'm not sure how that would work.
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "Shaun Oliver" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, March 18, 2008 8:03 AM
> Subject: Re: tone oscillator.
>
>
>> perhaps without drilling holes in teh rig one could modify the morse key
>> jack to provide power for such a device?
>>
>>
>> On 19/03/2008 12:37 AM, the old scribe known as Martin McCormick was
>> able to impart this pearl of wisdom:
>> > One thing I saw on an old Heath Kit Warier linear which
>> > had been outfitted with an audio tuning device was a
>> > quarter-inch stereo headphone jack on the rear of the chassis.
>> > Somebody had run coax designed for balanced audio service from
>> > the stereo jack to the two contacts of the meter on the front
>> > pannel.
>> >
>> > This would be a good way to do the modification.
>> >
>> > Balanced-line audio coax has 3 conductors. There is the
>> > shield plus two center wires instead of 1. One would want to
>> > route it so that it is as far away from the high-power RF
>> > circuitry as possible so one doesn't induce RFI in to the
>> > tone oscillator or the meter, itself.
>> >
>> > It is likely that both sides of the meter are above
>> > ground, hince the balanced coax.
>> >
>> > Of course two runs of regular coax would also work.
>> >
>> > Martin McCormick WB5AGZ Stillwater, OK
>> > Systems Engineer
>> > OSU Information Technology Department Network Operations Group
>> > Walt Sebastian writes:
>> >> Hi Shaun,
>> >> It seems to me, back in the olden days when I had a Kenwood TS520, I
> could
>> >> go about 50 to 60 KHz before I tuned up. I am sure other people
>> >> tuned
> up
>> >> sooner than that.
>> >>
>> >> Walt
>> >> WA4QXT
>> >> New London CT
>> >> [log in to unmask]
>> >>
>> >
>> >
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>>
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> 10:48 AM
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>
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>
>
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