Hmm, Ira,
Harmonics... The 4th is at 10 - 20-1st 40-2nd- 80-3rd- 160 -4th kHz.
Just took the 4th from the message without calculating . My fault. Let's
try this again. The sums of the 12th and the 14th add up into the VHF
band and add up to about 3 mV, still enough to cause trouble. Agree,
capacitors would prevent interference, and do not load a 10 khz pwm.
I'll wait with a reply next time till after coffee :-)
Jos Okhuijsen
irampil@notes.cc.sunysb.edu wrote:
>
>Hi Jos,
>
>Just a second here :-)
>You mean to say that 0.01mfd ceramic caps are going to load down the pwm?
>whoaaaaaa!
>You mean to seriously post that a 4th harmonic of 10kHz (i.e., 40 kHz on a
>vhf tuned dipole is going to do anything at all? whoaaaa.
>You think that even running close and parallel, that a 10 volt (15 ma)
>current parallel to the antenna for the whole length of the plane is going
>to
>induce 750 ma in the antenna? whoaaaaaaaa
>
>
>Don't take me too seriously, but I used to play an engineer on TV (slow
>scan TV that is)
>
>Ira
>
>
>Jos Okhuijsen <josok@ukolo.fi>
>Sent by: owner-europa-list-server@matronics.com
>06/24/03 02:40 AM
>Please respond to europa-list
>
> To: europa-list@matronics.com
> cc:
> Subject: Re: Europa-List: LEDs
>
>
>Some simple math:
>4 harmonics -> 4 x 3 db = -12 db
>12 V -12 dB = 750 mV over any wiring carrying the load.
>If the length of the wiring comes anything close to the wavelength, half
>or quarter of the comm freq's, adding a working antenna to this
>transmitter design, you might be a nuisance to anything in quite a
>reasonable range in addition to your own problems. Bypass capacitors?
>Will load (overload?) the square wave generator.
>
>Jos Okhuijsen
>
>
>
>
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