2 Wrote:
>// Do two equal-capacitance paralleled caps have a resonance?
>
They do not develop a new parallel resonance due to being connected
together.
And later:
>// In my experiences 50, 57, and 58 Series doorknob caps have a
>resonance at VHF or UHF. A 0.01uF disc ceramic cap resonates c. 10MHz.
>
Certainly - these are all *series* resonances with their self-inductance
(plus the inductance of the wire you used to "short" the cap for
dipping).
>// Mr. Rauch stated that the dipmeter adapter does not work correctly.
>
I seem to remember he said that MFJ marketed it against his advice - but
the MFJ analyzer manuals do give details of the methods I suggested,
which are superior to dipping.
>>Most modern CF/MO resistors have a spiral element, but if you scrape off
>>the paint, measure the diameter and length, and count the turns, you can
>>estimate the inductance using the normal coil formula. You'll find that
>>at low impedance levels the inductance is generally too small to matter
>>below 30MHz.
>>
>// ... which is about as useful as teats on a boar.
>
I bow to your obviously extensive knowledge of porcine anatomy... but
not to your engineering judgement.
--
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.com/g3sek
--
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