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RE: AIDC 3373 and a newbie to 2.4Ghz



It is possible, the VK5EME frequency doubler kit (used for doubling a 1200
MHz VCO to 2400 for ATV) is exactly this, but I think it's somewhat broader
than 50 MHz.  If you use a higher generator frequency, PCB
microstrip/stripline filters are more practical.

Don't ask me for a design though, I never did go on to do RF engineering. :(

Tony Langdon. 
Systems Development and Support. 
ATC Training Australasia.  Level 2 321 Exhibition St Melbourne  3000. 
Phone:  1300 13 1983     WWW:  http://www.atctraining.com.au 



> -----Original Message-----
> From: Vince R. [mailto:vincesr@ij.net]
> Sent: Tuesday, 10 April 2001 5:06
> To: Gary "Joe" Mayfield; Kevin Uhlir; amsat-bb@AMSAT.Org
> Subject: Re: [amsat-bb] AIDC 3373 and a newbie to 2.4Ghz
> 
> 
> Dear Group,
> Newbie here!
> 
> Anyone know if it is practical or possible to build a
> 2401 Mhz bandpass filter with a simple PCB? What I am trying to
> do is to "filter" the output of a simple "harmonic" signal generator.
> 
> I'd like a bandpass of maybe 50Mhz. If someone could point me to
> the appropriate reading material on the design of microstrip filters,
> etc. I'd like to learn more...
> 
> What is the conscensus on the best (in print) books to  get started
> with on microwave design? If anyone in the Tampa, FL area knows
> of a decent engineering library with books on the topic, that would be
> very helpful.
> 
> Thanks,
> Vince Risalvato
> KD7AI
> 
> ----- Original Message -----
> From: "Gary "Joe" Mayfield" <gary_mayfield@hotmail.com>
> To: "Kevin Uhlir" <kevinu@flochart.com>; <amsat-bb@AMSAT.Org>
> Sent: Sunday, April 08, 2001 11:07 PM
> Subject: Re: [amsat-bb] AIDC 3373 and a newbie to 2.4Ghz
> 
> 
> > Kevin and Group ,
> >
> >      Here is what I have seen..
> >
> > Lot's clipped
> >
> > > listening at MA28-50 and MA240-250.  Farthest distance 
> was 44,000km,
> > nearest
> > > was 9,500km.  I have the 3'x2' barbeque dish, and an 
> untouched AIDC3373.
> >
> > We have identical setups.  I have never copied at 44,000 km 
>  at 9,500 my
> > setup will hear it, but probably not decode anything.  
> AO40Rcv will try to
> > sync, but never suceed.  I have gotten blocks in a little 
> closer, and I have
> > gotten good CRC blocks closer still.
> >
> > > I'm new to 2.4G, but not at all new to satellites or RF.  
> I've worked
> > AO-10
> > > and AO-13 extensively.  I have no test equipment for 2.4, 
> nothing to
> > > generate a signal... Actually nothing to generate an RF 
> signal at all
> > except
> > > for various HF, VHF and UHF transmitters. I do have a 
> 1.2G xverter (in
> > need
> > > of repair!).
> >
> > I have no special test gear for  S-Band either. I lashed 
> together a harmonic
> > generator (5 1/2 Watt 47K Ohm resistors in parallel with a 
> 1N4005 diode) as
> > seen on K5OE's web page.   My handheld will TX out of band, 
> so I did the
> > following.  If you feed the 'harmionic generator' with  
> 141.175 MHz the 17th
> > harmonic comes out at 2399.975 MHz (141.180 yields 2400.060 
> MHz / 144 MHz
> > yield 2448.000 MHz)  I think you get the picture.  Spin 
> around the expected
> > output of the converter until you find the signal.  Repeat 
> this with several
> > different frequencies being fed into your 'harmonic generator'.  The
> > frequency of the down conversion should remain constant.  
> My downconverter
> > always downconverts by 2277.988 MHz (i.e. 2400.060 MHz into the
> > downconverter shows up at 122.072 MHz on my receiver).
> >
> > > 1) How acurate is the frequency of these 
> downconverters....  How large a
> > > search range should I use to find 2401.318?  100Khz?  
> 500Khz?  1Mhz?
> >
> > They are not acurate, by ssb standards, but they should be 
> repeatable!  Note
> > my above paragraph.
> >
> > > 2) Whats the simplest way to create a test signal on 
> 2400?  My 1.2G
> > xverter
> > > is in need of repair, but even so, i use my IC-706 for 
> the IF for that
> > too.
> > > I have HF thru 440Mhz working, and a frequency counter 
> that goes to 1Ghz.
> >
> > The quick and dirty 'harmonic generator' seems sufficent.
> >
> > >
> > > 3) What test equipment might I find useful, plentyful 
> (read as cheap) for
> > > use up here?  I do enjoy home brewing, but I'm usually at 
> a loss as to
> > what
> > > to build for 1Ghz+.  I'm completly a newbie with regard 
> to MMIC's and
> > stuff
> > > (altho they sure do seem like "connect the dots" and they 
> just work!)
> > >
> > I've gotten close enough decode using FODTrack to point the 
> antennas, and
> > adjust the doppler completely unattended.  Nothing special 
> here.  I might
> > add I also put some time and effort in re-aligning my 
> antennas.  The 2' x 3'
> > dish seems to be narrower (no real suprise) than my 2 meter 
> and/or 70 cm
> > Yagi.  I just 'eyeballed it' on the North star.
> >
> > 73, and Good Luck,
> > Joe
> > ka0yos@amsat.org
> >
> >
> > > Thanks in advance!
> > > Kevin Uhlir
> > > N0BEL
> >
> > ----
> > Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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> 
> ----
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