Ok Minto
This implies it can address the via the serial link , if so , then
its a way in ?
73 -G,
http://designtools.analog.com/dt/dds/ad9850.html
--------------------------------------------------
From: "Minto Witteveen" <[email protected]>
Sent: Tuesday, January 08, 2013 9:23 PM
To: <[email protected]>
Subject: LF: Re: 475kHz crystal
Graham,
Did you find a website of the mfg of this specific board? I can’t find it,
although there is plenty of info on the Internet for this specific board
(pin layout, programming specs). And of course 9850 datasheets on the
website of Analog Devices, the mfg of the DDS chip itself.
Can you point me to the website with the pc based support software, I will
look into it to see what it can do. But whatever the software can do, you
still need to interface the SPI, and a ‘standard’ PC has only the
parallel interface that can be used..
Minto pa3bca
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Ceterum censeo Carthaginem delendam esse
-----Original Message-----
From: Graham
Sent: Tuesday, January 08, 2013 22:06
To: [email protected]
Subject: Re: LF: Re: 475kHz crystal
From the mfg web-site , seems to be pc based support software ?
could not this be used to run the 'dds demonstration kit' directly
?
--------------------------------------------------
From: "Minto Witteveen" <[email protected]>
Sent: Tuesday, January 08, 2013 8:42 PM
To: <[email protected]>
Subject: LF: Re: 475kHz crystal
Hi Graham,
It is possible to use the parallel port of a PC to control the DDS, the
DDS has a 3-wire SPI interface. See for instance:
http://www.qsl.net/p/pa3ckr//signalgenerator/ . Here you will find
(amongst a lot of other info) a VB program to control the DDS
(http://www.qsl.net/p/pa3ckr//signalgenerator/prad9850.zip). But be
prepared to re-install W95 or possibly DOS because it will not work with
newer versions of windows….
Using a PIC is the easiest method I think. Andy already beat me to it,
see his earlier reply to my mail. If you do not want to make a PCB you
can even build it using a prototyping breadboard.
Minto pa3bca
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Ceterum censeo Carthaginem delendam esse
-----Original Message-----
From: Graham
Sent: Tuesday, January 08, 2013 21:16
To: [email protected]
Subject: Re: LF: Re: 475kHz crystal
Minto
Is it possible to communicate with the DDS from the PC for a
simple
VFO or need the pic ?
G.
--------------------------------------------------
From: "Minto Witteveen" <[email protected]>
Sent: Tuesday, January 08, 2013 6:46 PM
To: <[email protected]>; <[email protected]>
Subject: LF: Re: 475kHz crystal
Or, as long as you are going to use a PIC anyway, order a AD9850 DDS
module from buyincoins.com. This 0-40MHz DDS costs less than $5
(including shipping). Add a cheap PIC, a $5 2x16 LCD and a rotary
encoder (or use your PC to communicate with the PIC) and you can
generate any frequency you want. And use the PIC to generate Opera,
wspr, qrss.
My next project. I already have all the components….
Minto pa3bca.
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Ceterum censeo Carthaginem delendam esse
-----Original Message-----
From: Klaus Hirschelmann
Sent: Tuesday, January 08, 2013 12:00
To: [email protected]
Subject: Re: Fw: LF: 475kHz crystal
Hi Pete and group
maybe we can bring http://www.hanssummers.com/ for also offering
630m-Band versions of his QRSS and WSPR kits.
He doesn't seem to have taken MF on board as far as I can see. May one
of his rigs can be modified I have not checked my self.
He does mention the use of Si570 programable xtal. I have one on a board
with set frequencies from a PIC and selected by binary from a dil
switch.
They will not operate as low as 500kc/s so they have to be divided with
either a CD4040 or CD4060 or any other logic divider. However it gives
stable selectable xtal frequencies. In this case it is probably worth
going
the extra mile and make up a DSS as the master oscillator which will
give
VFO coverage. I think your pays your money and takes you choice as they
say....... hee.
What i intend to do, is building a relatively simple Stand-Alone WSPR
beacon
for 630m-Band. Using a Si570 with additional divider seemed to be quite
an
expensive solution. So i did order 7611.2 KHz crystal ( there is a
company
manucturing crystals according to given frequency ). By using a HCF4060B
oscillator/divider this should give a stable signal around WSPR midden
frequency 475.7 KHz. WSPR signal generation is planned according to
http://www.knology.net/~gmarcus/WSPR/WWVB_WSPR%20VCXO%20Contoller.pdf
where
( for use in Europe ) i intend to use DCF77 time signals instead of
WWVB.
Suitable PIC program version is made by PE1NWL and available via
http://www.knology.net/~gmarcus/ , while DCF77 receiver module is
obtainable
from Conrad Electronics.
Because of later signal division by 16, this conception will require a
multiplication of crystal FSK deviation by same factor. For WSPR this
should
result in values around 23.43 Hz which ( i hope ) will not cause any
problem.
So far my plans in the moment, but of course it would be much easier, in
case somebody would offer a kit already doing all i like.
..
Klaus, DJ7OO
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