>Rich,
>
>Seems that issue is not that effective resistivity of nichrome increases
>with decreasing frequency - I don't think anybody is arguing that.
Mr. Rauch has. He has also argued that most of current flows in the
resistor instead of the inductor. In the 28-November sample problem he
proposed, slightly more than half of the current flowed through the
inductor
>What is evident is that the effective series resistance of the nichrome
>suppressor is higher than conventional suppressor at low frequencies. From
what I
>can see, this seems to be the basic tradeoff between the nichrome
>suppressors
>and the conventional suppressors. If I am recalling the test data correctly,
>the nichrome suppressor has higher losses at moderate VHF frequencies
>(50 to 100 MHz) - a good thing, at the expense of higher losses in the HF
>frequency range (a bad thing).
So far, no one has reported seeing a drop in HF power. Presumably, a 1%
change on 10m barely shows up on the average meter. In my opinion, the
HF loss issue is a red herring.
end
> As the frequency increases further the
>the two suppressors start to converge as the inductive reactance of the
>nichrome suppressor starts to dominate over the resistance of the wire.
>No rocket science here.
>
>Mike, W4EF...................................
>
>
>----- Original Message -----
>From: "measures" <2@vc.net>
>To: "AMPS" <amps@contesting.com>
>Sent: Saturday, October 14, 2000 12:14 AM
>Subject: Re: [AMPS] a sticky issue.
>
>
>>
>> >At 08:01 PM 10/13/00 -0700, you wrote:
>> >>
>> >>According to Wes, the copper-wire suppressor had an Rp of 166-ohms at
>> >>100MHz and the resistance-wire suppressor had an Rp of 101-ohms. More Rp
>> >>means more gain. Are you arguing the opposite, Bill?
>> >
>> >Rich- I am NOT arguing either way, which may surprise you- You are missing
>> >the point- your problem is that you misstate other peoples arguments-
>> >exaggerate their position, and make ALL debate into a personal attack.
>> >Your reference to others as "lapdogs" is a case in point- THat was uncalled
>> >for,
>>
>> During the grate debate, Tom's faithful lapdogs attacked my 1/1994 QST
>> article, The Nearly Perfect Amplifier and stated that a rheostat simply
>> will not work for adjusting filament potential (sic).
>>
>> >and made several people upset. some of the ones most upset were people
>> >who dont like Tom , either.
>> >
>> >>
>> >>Do you believe that the RF resistance of nichome wire increases as
>> >>frequency decreases?
>> >
>> >Rich- I KNOW that the resistance of Nichrome wire changes with frequency.
>>
>> ok
>>
>> >What I don't know is just where (what frequency range) , and how much it
>> >changes. I only know that at very low frequencies, it is higher that it is
>> >at very high frequencies.
>>
>> The resistance of all conductors increases as frequency increases. As
>> frequency increases, skin depth decreases, and conductivity decreases.
>> This is why 10m tank inductors need more copper than 80m tank inductors.
>> // In Wes' measurements, the resistance of the nichrome inductor - with
>> no parallel resistor - changes from 15-ohms at 10 MHz to 45-ohms at
>> 200MHz. Rauch's assertion that nichrome is different than all other
>> conductors is a laugher.
>>
>> >Again- this has NOTHING to do with the problem. You keep interjecting this
>> >into posts on other subjects as if it was a sever indictment and a MAJOR
>> >error.
>>
>> It undoubtedly is.
>>
>> > You have taken this out of context, with mystifying results to all
>> >newcomers,
>>
>> How do you know what all newcomers think?
>>
>> cheers, Bill.
>>
>> - Rich..., 805.386.3734, www.vcnet.com/measures.
>> end
>>
>>
>> --
>> FAQ on WWW: http://www.contesting.com/FAQ/amps
>> Submissions: amps@contesting.com
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>> Problems: owner-amps@contesting.com
>>
>>
>
>
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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