One of the often overlooked Tuners are the Murch UT-1000 and UT-2000.
They have not been made in many years and sell for much less than their
more modern (and expensive) counterparts.
The UT-2000B will cover 160 - 10 and will load up the proverbial bedspring.
They show up over on the "evil empire" from time to time.
73, Dick, W1KSZ
On Sun, Feb 2, 2014 at 2:37 PM, Roger (K8RI) <k8ri@rogerhalstead.com> wrote:
> On 2/2/2014 2:11 PM, qrv@kd4e.com wrote:
>
>> Weird amps list error the first try - trying again ...
>>
>> Roger,
>>>
>>> Would you please explain "hiss"?
>>>
>>
> iss as in hi voltage arc. Sounds just like a cat or snake.
>
>
>>> What, precisely, is happening to create that sound?
>>>
>>
> If the antenna in highly reactive (inductive) and the SWR is high the
> voltage goes high.
> Neither the MFJs or Dentrons had a high enough voltage rating for much
> over what I'd get when the 160 antenna was resonant near the DX window and
> I'd go to the top of the band.
>
> Moving the resonant point to the middle, or upper end of the band would
> eliminate the arcing at 1 KW, but then I had concerns about the small wire
> on the rotary inductor when operating at the bottom end of the band.
>
> They really needed a higher voltage rating on a larger cap and a larger
> size wire on the rotary inductor for current on low impedances.
>
> 73
>
> Roger (K8RI)
>
>
>>> There are so few parts involved it seems that there's
>>> either too small inductance (or perhaps the gauge of the coil
>>> wire is undersized), too little capacitance (or perhaps aging
>>> doorknob capacitors), or a tiny arc across an under-rated switch?
>>>
>>> Could it be that a small tweak to one part of the mix of
>>> parts could compensate for the weakness elsewhere e.g. adding
>>> capacitance balances the added stress at 160m such that the
>>> marginal coil or switch is not pressed to the limit?
>>>
>>> Trying to understand the "why" behind the symptoms ...
>>>
>>> Thanks!
>>>
>>> David
>>>
>>> I've had no problems with the half sloper, center fed droopy dipole
>>>> on 160, or the Fan Dipole on 75. The Dentrons and MFJ 989 series
>>>> would all "hiss" at me on 160 near the top end of the band at much
>>>> over 1 KW out.
>>>>
>>>> 73,
>>>>
>>>> Roger (K8RI)
>>>>
>>>
>>
>>
>>
>
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