I guess you are only familiar with leading Ts and not lagging networks.
On 5/4/12 9:52 PM, Carl wrote:
> True. they can be no pass and the coil becomes the dummy load. Very easy to
> do if not familiar with a T tuner.
>
>
> ----- Original Message -----
> From: "W2XJ"<w2xj@nyc.rr.com>
> To:<amps@contesting.com>
> Sent: Friday, May 04, 2012 5:22 PM
> Subject: Re: [Amps] Antenna tuner loss
>
>
> Ts are not necessarily High pass nor are Ls for that matter.
>
> On 5/4/12 4:59 PM, Rob Atkinson wrote:
>> I wouldn't touch a T network. High pass = no pass here
>>
>> 73
>>
>> Rob
>> K5UJ
>>
>> On Fri, May 4, 2012 at 8:37 AM, Tom Thompson<tlthompson@qwest.net> wrote:
>>> Kevin Schmidt, W9CF, has a nice Java app where you can study the losses
>>> in a T-network tuner at http://fermi.la.asu.edu/w9cf/tuner/tuner.html
>>>
>>> Tom W0VJ
>>>
>>> On 5/4/2012 7:22 AM, Carl wrote:
>>>> The first series of tests even had the MFJ coils catching on fire in the
>>>> ARRL lab at well under power ratings on 160.
>>>>
>>>> Tuners with 250pf max on 160 will always be inefficient, a High C tuner
>>>> with
>>>> 500pf will be very efficient and require proportionally less L. The
>>>> higher Q
>>>> results in less bandwidth so there is no free lunch.
>>>>
>>>> Its so much easier to modify an amp to be able to do the matching and
>>>> toss
>>>> the tuner in the dumpster.
>>>>
>>>> Those with autotune amps are left swinging in the wind and need autotune
>>>> tuners (-;
>>>>
>>>> Carl
>>>> KM1H
>>>>
>>>>
>>>>
>>>> Carl
>>>> KM1H
>>>> ----- Original Message -----
>>>> From: "Roger (K8RI)"<k8ri@rogerhalstead.com>
>>>> To:<amps@contesting.com>
>>>> Sent: Friday, May 04, 2012 3:32 AM
>>>> Subject: Re: [Amps] Antenna tuner loss
>>>>
>>>>
>>>> On 5/3/2012 12:32 PM, Dan Hearn wrote:
>>>>> ARRL tested some popular commercial antenna tuners and reported the
>>>>> results in QST as follows. They covered 160-10 and various loads. All
>>>>> were
>>>>> quite lossy on the low bands with low Z loads.
>>>> And there are people out there that didn't expect this? They are
>>>> running into low impedance loads which means high currents and high
>>>> losses. I believe the Palstar manual even mentions this. Also the
>>>> power handling capability drops off substantially with low Z loads
>>>>
>>>> 73
>>>>
>>>> Roger (K8RI)
>>>>> February, 2003
>>>>> Product Reviews
>>>>> High Power Antenna Tuners:
>>>>> • AMERITRON ATR-30
>>>>> • MFJ-986
>>>>> • PALSTAR AT1500CV
>>>>> • TEN-TEC 238A
>>>>> • VECTRONICS HFT-1500
>>>>>
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