Circuit needed for a VCO & Amplifier

alfred ee newman

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Jun 16, 2002, 2:20:25 AM6/16/02

to

I am a struggling self-taught/teaching electronic hobbyist.

I would like to build a VCO cicuit adjustable from about 200 MHz or so
to
about 400MHz or so, sine wave.

With the wave output from the VCO, I would like to apply an amplifier
to
it to increase its voltage or power as high as possible.

Any help is much appreciated. I've tried burying myself in books from
my local library and bookstore, but I'm still pretty lost.

Thank you.

Phil Allison

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Jun 16, 2002, 2:30:59 AM6/16/02

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"alfred ee newman" <alfrede...@hotmail.com> wrote in message
news:6bc52f47.02061...@posting.google.com...

** That is a *MAD* idea, Alfred.

Regards, Phil

John Woodgate

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Jun 16, 2002, 5:33:44 AM6/16/02

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I read in sci.electronics.design that alfred ee newman
<alfrede...@hotmail.com> wrote (in <6bc52f47.0206152220.49a4114f@pos
ting.google.com>) about 'Circuit needed for a VCO & Amplifier', on Sat,
15 Jun 2002:

I feel sure that the FCC will give you all the help you deserve.
--
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
Interested in professional sound reinforcement and distribution? Then go to
http://www.isce.org.uk
PLEASE do NOT copy news posts to me by E-MAIL!

Michael A. Terrell

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Jun 17, 2002, 1:24:21 AM6/17/02

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http://www.minicircuits.com/ has some resonably priced VCO modules.

Phil Allison

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Jun 17, 2002, 2:00:55 AM6/17/02

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"Michael A. Terrell" <ter...@mfi.net> wrote in message
news:3D0D7285...@mfi.net...

** Did you sell guns to Indians in a past life??

Love, Phil

Rene Tschaggelar

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Jun 17, 2002, 6:20:17 AM6/17/02

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guns and whisky.

Rene

Leon Heller

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Jun 17, 2002, 6:40:23 AM6/17/02

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"Phil Allison" <bi...@bigpond.com> wrote in message
news:zNeP8.13837$Hj3....@newsfeeds.bigpond.com...

They also sell high-power broadband RF amps to go with them!

Leon
--
Leon Heller, G1HSM leon_...@hotmail.com
http://www.geocities.com/leon_heller
Low-cost Altera Flex design kit: http://www.leonheller.com

J M Noeding

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Jun 17, 2002, 1:52:59 PM6/17/02

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On Sun, 16 Jun 2002 10:33:44 +0100, John Woodgate
<j...@jmwa.demon.contraspam.yuk> wrote:

>>I would like to build a VCO cicuit adjustable from about 200 MHz or so to about 400MHz or so, sine wave.
>>
>>With the wave output from the VCO, I would like to apply an amplifier to it to increase its voltage or power as high as possible.
>>
>

>I feel sure that the FCC will give you all the help you deserve.

seems to be the sort of things we once dealt with in Her Majesty's
Service, but perhaps we just misunderstood the intentions?
What about MCL?

jm

--
remove ,xnd to reply

artie

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Jun 17, 2002, 11:28:49 PM6/17/02

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Not only does Mini Circuits Lab (http://www.minicircuits.com) have VCOs
and amplifiers, they also have some very good design guides.

And don't worry about being lost -- depending on what frequencies you
run on, you'll be found very soon...

namaste-

In article <6bc52f47.02061...@posting.google.com>, alfred ee

alfred ee newman

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Jun 18, 2002, 4:12:51 PM6/18/02

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Thank you all for your input to my original post. I really appreciate
it, even the tounge-in-cheek FCC comments.

I apologize for not making myself more clearer. I am not interested
in generating radio spectrum transmissions. Quite the contrary, I
want to use the requested circuitry in a laser device.

Taking your previous comments into consideration and some more
"research" on my part, I have come up with the following scheme.
Please let me know what you think about it and please share any ideas
or suggestions you may have.

Thank you.

sine wave from a VCO (between about 100 and 200 MHz)
goes to a
frequency doubler (to get between about 200 and 400 MHz)
which goes to an
amplifier (which increases power up to the desired level)

Another question: even though this circuitry is not connected to an
antenna, is it still possible for it to transmit radio signals? If
so, can the project be shielded to prevent any radio signals from
goinmg out?

Thanks again.

Jim Thompson

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Jun 18, 2002, 4:22:31 PM6/18/02

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On 18 Jun 2002 13:12:51 -0700,
ALFREDE...@HOTMAIL.COM (alfred ee newman),
In Newsgroup: sci.electronics.design,
Article: <35f63307.02061...@posting.google.com>,
Entitled: "Re: Circuit needed for a VCO & Amplifier",
Wrote the following:

Try to find an MC12048 VCO. You should be able to make 400MHz
directly.

For proper E-mail replies SWAP "-" and "_"

I love to cook with wine. Sometimes I even put it in the food.

Dave M

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Jun 18, 2002, 6:56:45 PM6/18/02

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Yes, any device is capable of radiating unintended RF. The levels of
radiation you experience will depend upon a number of things, such as the
power levels of the RF within your device, existence and effectiveness of a
ground plane, construction techniques, presence and effectiveness of
bypassing on power supply and other external signal connections, type of
enclosure around your circuit, and on and on...
Certainly, your circuit can be shielded, but the shielding technique you
need to use will again depend on the allowed maximum levels of radiation
allowed from your circuit to meet FCC requirements, plus all the issues
above.

--
Dave M dgma...@atxxt.net
Remove the xx for my correct email address
ab...@yahoo.com; ab...@lycos.com; ab...@hotmail.com

"alfred ee newman" <ALFREDE...@HOTMAIL.COM> wrote in message
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