>Sorry Carl,
>
>...snip... ... it is the
>external resistor and the inductance value that mainly controls
>VHF Q.
>
The Tom Rauch/W8JI vhf suppressor had slightly more R and slightly more L
than the resistance-wire (Handy-Measures) vhf suppressor - so it had a
slight advantage. However, at 150MHz, according to Mr. Stewart, the W8JI
suppressor had 44% more Q and 59% more Rp than the Handy-Measures
suppressor.
>...snip...
>Once the resistor is there, the Q of the material in the inductor
>(or the inductors Rp) matters very little. A very slight adjustment
>in turns and / or resistance would easily make the two
>methods identical in system performance at VHF.
If that's true, then why did Mr. Rauch cancel his post of 28 November
1986 - wherein he proposed calculating the effect of 5 ohms of ESR in Ls?
- - and why did he stonewall the issue ever since? How about telling
us why you cancelled the post, Mr. Rauch?
>
During the grate suppressor debate, I repeated asked Mr. Rauch to design
a copper-wire parasitic suppressor that equaled the performance of the
resistance-wire suppressor. I repeatedly asked Ian White and Wes to
design one. ......... So far, nothing.
>At lower frequencies, it is another matter. Much more current
>flows through the inductor than the resistor. On ten meters, the
>nichrome suppressor would have much less Q ...
To see if this checks out, see Wes' measurements.
Rich---
R. L. Measures, 805-386-3734, AG6K
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