From: Rik Strobbe <Rik.Strobbe@fys.kuleuven.be>
To: "rsgb_lf_group@blacksheep.org" <rsgb_lf_group@blacksheep.org>
Thread-Topic: LF: RE: Analog oscillators
Thread-Index: AQHNWsyoHzOh5uRB8UGx+IA5i5SJQZcayFcAgAACiACAADnwcA==
Date: Thu, 5 Jul 2012 18:38:24 +0000
Message-ID: <7E7DFBB4D102A04DB5ADC88D66628A4A0FAB99CC@ICTS-S-MBX5.luna.kuleuven.be>
References: <KOEAKFKINDBIGKCFCJEDGEBJCAAA.victor13@online.nl>,<4FF5CA64.8020202@iup.uni-heidelberg.de>
In-Reply-To: <4FF5CA64.8020202@iup.uni-heidelberg.de>
Accept-Language: nl-BE, en-US
Content-Language: nl-BE
MIME-Version: 1.0
Subject: RE: LF: RE: Analog oscillators
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
X-AOL-SCOLL-URL_COUNT: 0  
x-aol-sid: 3039ac1d40844ff5df663676
X-AOL-IP: 195.171.43.25
X-AOL-SPF: domain : blacksheep.org SPF : none


Stefan,

what about a huff&puff oscillator (http://www.hanssummers.com/huffpuff.html=
) ?

73, Rik  ON7YD - OR7T

________________________________________
Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org=
] namens Stefan Sch=E4fer [Stefan.Schaefer@iup.uni-heidelberg.de]
Verzonden: donderdag 5 juli 2012 19:09
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: Re: LF: RE: Analog oscillators

Hi Victor,

Am 05.07.2012 19:00, schrieb victor13@online.nl:
> Hello Stefan,
>
> for narrowband vfo i get best results with a clap or a seiler,both with b=
ig
> parallel c over the FET.But of course everything depends on the mechanica=
l
> stability and the quality of the parts: ceramic coilformer,silvered mica
> capacitors and tempcompensation with N750 ceramic capacitors.With trial a=
nd
> error you may get very good results.
OK, tnx. Years ago i built a 137 kHz oscillator (by DJ2EY) which used
diffent capacitors for temperature compensation. I will see what i get...

> Use big parts,temprise will be less,so
> stability will be better..
>

That sounds convincing, tnx. Meanwhile the output stage is built, once
again using a ICL7667. I would like to use a JFET. And i found a nice
link in the web, of course from W1VD: http://www.w1vd.com/16080VFO.pdf

That is nice and i have all the parts here. I will build it and hope to
try it in the evening :-)

BTW are you QRV on 500 CW as well?

73, Stefan




> GL
> 73
> Victor
>
> -----Oorspronkelijk bericht-----
> Van: owner-rsgb_lf_group@blacksheep.org
> [mailto:owner-rsgb_lf_group@blacksheep.org]Namens Stefan Sch=E4fer
> Verzonden: donderdag 5 juli 2012 18:32
> Aan: rsgb_lf_group@blacksheep.org
> Onderwerp: LF: Analog oscillators
>
>
> LF/MF,
>
> I want to build an analog oscillator running on 1888....1916 kHz. It
> will be used as the input VFO for my PA which divides the frequency by 4
> internally. A metallic box with 12V input voltage cables and a RG174
> cable for the output is already available. Also a 78L05 with its 100nF
> Cs is mounted. Later i can label the scale directly with 472...479 kHz,
> so the need to divde by 4 in my head will not be necessary any more.
>
> The output voltage should be arround 12V. The curve form is not
> critical, it does not need to be a clear sine wave. However the
> frequency should be as stable as possible.
>
> So, what is the best oscillator circuit? Are there strong differences
> regarding stability or is it always a question of the temperature? Ah,
> it must be a LC oscillator. The adjusting part is a variable C of 33pF
> with a 6mm axis.
>
> There are a lot of circuits in the web but maybe one principe is to be
> preferred..
>
> 73, Stefan/DK7FC
>
>
>
>
>=