Frequency sintetizer for heterodyning

[Alessandro Esposito]

Hi,
I have two very wonderful IFR signal generators but also quite
expensive. They are perfect but I want to test some cheap version of my
instrument that is an advanced microscope.
I know people replaced, in applications as mine, a signal generator with a
NE555... wow... I mean... I worked with NE555 14 years ago when I was 14
y.o.
At the moment I'm working at MHz region with two equal but tuneable
frequencies with a certain phase delay between them. Supposing to move in
the KHz region I think I could use NE555.
So the questions are:
1) does exist an easy way to use to coupled NE555 with the same frequency
but with a adjustable phase delay between them?
2) is it possible to use NE555 to have two slightly different frequencies,
in the way I can control the difference?
3) is there some chip easy to use as the NE555 but that work in the MHz
region?

Ok... I thank you anyway... hoping for some suggestion or references. Is
there some website with schematics?
Bye
Alessandro
----
theopps75@yahoo.it
ENI-Göttingen

 

[Fred Abse]

On Wed, 20 Aug 2003 06:53:07 +0100, Mantra wrote:

555's are intended for
applications where you simply need a signal that mostly goes up-and-down
(AC) at roughly a given frequency give-or-take double-digit
(in)accuracy.

I thought they were for giving to students to play with

--
Then there's duct tape ...
(Garrison Keillor)
nofr@sbhevre.pbzchyvax.pb.hx

 

[Alessandro Esposito]

in that case was not for heterodyning but homodyning and was a work in which
they didn't need do be very precise.
In my case I could try to "downgrade" all the system for particolar
application.
Anyway I got that for these reasons is impossibile to make heterodyning for
the intrinsic unstability.
Not a problem I think... there are a lot of low-cost possibility

"Fred Abse" <excretatauris@cerebrumconfus.it> wrote in message
newsan.2003.08.20.20.06.14.496820.656@cerebrumconfus.it...

On Wed, 20 Aug 2003 06:53:07 +0100, Mantra wrote:

555's are intended for
applications where you simply need a signal that mostly goes up-and-down
(AC) at roughly a given frequency give-or-take double-digit
(in)accuracy.

I thought they were for giving to students to play with

--
Then there's duct tape ...
(Garrison Keillor)
nofr@sbhevre.pbzchyvax.pb.hx