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Re: AIDC 3373 and a newbie to 2.4Ghz



Hi Bill & Vince:

I had tried to find the file on this 13 cm Source Bill, but did not have any
luck.  Thanks to Vince for finding it.

I built this unit about 2 years ago, before I bought my microwave sweep
generator.  The source puts out a very clean signal that is ideal for tuning
S-band converters and preamps.  I used a 100 MHz. TCXO and the signal is
very clean and stable.

I also built one using a 50 MHz. oscillator module from an old PC
motherboard.  Although not as stable, nor as accurate as the one built with
the TCXO, it still provides a reasonably accurate and stable source for
tuning downconverters and preamps.

I had planned on building one of these sources using a precision 10 MHz.
OCXO, but before I had a chance to build it, I bought the microwave sweep
generator.  Although I have not tried it, I would expect it to work fine in
this application (yes, I know - famous last words).

Good luck.

73,

Woody
KJ4SO

----- Original Message -----
From: "Bill Howell" <bhowell@mail.utexas.edu>
To: "Vince R." <vincesr@ij.net>
Cc: "Amsat List" <amsat-bb@AMSAT.Org>
Sent: Monday, April 09, 2001 16:13 PM
Subject: Re: [amsat-bb] AIDC 3373 and a newbie to 2.4Ghz


> Vince...
>
> This may be what you are looking for. It's a 50 mHz source with
> a 2400 Mhz tuned line :
http://www.havilandtelco.com/homepages/gregwycoff/tsld008.htm
>
> Two links on that page:
> "SIGNAL SOURCE PHOTO "
> "SIGNAL SOURCE SCHEMATIC "
>
>
>
>
>
>
> >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.
> >> To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
> >
> >----
> >Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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>
> --
>
> Bill Howell
> University of Texas at Austin
> College of Fine Arts
> Office of Computing Technologies
> N5ALO  Amsat 32459  QRP-L 415
>
> ----
> Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
>

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