DDS VFO plans
 

Just acquired a Small Wonder Labs "White Mountain 75" QRP SSB
tranceiver. It works quite well as designed but would like to add a
DDS VFO with LCD frequency readout and re-package it all mainly for
PSK use. Looking for plans with PCB patterns and any hex code for a
suitable DDS VFO, or alternatively a VCO stabilizer with freq readout.
Googling turned up a few articles but not a package that I can build
myself from scratch not a kit job. Any pointers greatly appreciated.

VE3ELQ Nigel In Embrun Ontario

"VE3ELQ" wrote in message
...

would like to add a DDS VFO with LCD frequency readout

Nigel

FAR Circuits has the PC board for the circuit described by WB2V in QEX.
This is pretty simple and works well, although the board quality from FAR
Circuits leaves something to be desired. I think you can also get a reprint
of the article from them. (http://www.farcircuits.net/vfo2.htm#2vfo).

Another approach is to build something up from the DDS Daughtercard from
AmQRP. This little board deals with all the hard stuff, but you would need
to sort out driving it yourself. (http://www.njqrp.org/dds/index.html).
AmQRP's PIC-EL provides an LCD display and drive for the board and is well
documented on their site. (http://www.amqrp.org/elmer160/board/index.html)
However, the PIC-EL itself is no longer available (and more that what you
need, anyway). But the schematics and code on the site could provide you
with what you need to roll your own.

The DDS Daughtercard is a nice approach because it mostly handles the hard
part. Most of the DDS chips are only in TSSOP or smaller. Making a PCB
that fine is a little tough for most hobbyists. The Daughtercard has the
DDS chip, the oscillator to drive it, a regulator, and a little amplifier to
get the output up a tad. It plugs into a normal 0.1" header. The thing is
really tiny so you have a lot of packaging options.

...

In article ,
says...
Just acquired a Small Wonder Labs "White Mountain 75" QRP SSB
tranceiver. It works quite well as designed but would like to add a
DDS VFO with LCD frequency readout and re-package it all mainly for
PSK use. Looking for plans with PCB patterns and any hex code for a
suitable DDS VFO, or alternatively a VCO stabilizer with freq readout.
Googling turned up a few articles but not a package that I can build
myself from scratch not a kit job. Any pointers greatly appreciated.

VE3ELQ Nigel In Embrun Ontario


Does it have to be an LCD display? G3XJP has produced a very good design,
which can be found at Analog's website with the following URL:
http://tinyurl.com/65ggv

Foil patterns etc are available for this design at
http://tinyurl.com/3k568

It is a very satisfying build - hex code for the PIC is available either
from Peter Rhodes G3XJP, or if you join the Pic-a-star Yahoo group, from
there.

Best of luck

Gary M0JJH

Nigel,
... would like to add a
DDS VFO with LCD frequency readout and re-package it all mainly for
PSK use. Looking for plans with PCB patterns and any hex code for a
suitable DDS VFO...

I have a follow-on for the Siggen project (i.e., Far Circuits board running
my Siggen3a code)
or my PICELgen code running the PIC-EL. It is going to be released by AmQRP
very soon.

My new DDS VFO (called IQ-VFO) has some significant advantages over the
previous
DDS VFO. This one uses a more advanced DDS (the Analog Devices AD9854)
which produces
two outputs (In-phase and Quadrature) on any frequency from 0 to 30 MHz.
The two signals
provide endless modulation/demodulation possibilities.

Full kits will be available as well as the bare boards, etc. My source code
for the two PIC
microcontrollers that control the IQ-VFO is also available so modifications
are encouraged/expected.

You can see detals about the IQ-VFO on my web page: www.cbjohns.com/aa0zz

Also, a few days ago I opened up a YAHOO group (called DDS-VFO) to discuss
DDS VFOs and
this IQ-VFO in particular. Please join us there.

73,
-Craig, AAØZZ

VE3ELQ wrote:
Just acquired a Small Wonder Labs "White Mountain 75" QRP SSB
tranceiver. It works quite well as designed but would like to add a
DDS VFO with LCD frequency readout and re-package it all mainly for
PSK use. Looking for plans with PCB patterns and any hex code for a
suitable DDS VFO, or alternatively a VCO stabilizer with freq readout.
Googling turned up a few articles but not a package that I can build
myself from scratch not a kit job. Any pointers greatly appreciated.

VE3ELQ Nigel In Embrun Ontario
Most of the designs out there use PIC micro's. Nothing wrong with that,
the pics are very good micros. HOWEVER, I think you guys should
consider the AVR MEGA chips. A real jtag ice is available for $300 from
Atmel, or you can build your own jtag interface or buy a clone for under
$50. (Google for 'bootice'. Uses only two IC's some connectors,
some connectors, a few resistors and a Led or two.)
A "C" compilier, assembler, and debugger is available for a free
download, and all the tools will work under Windows or Linux! The
Avr Mega series are available in 40 pin dip or 44 pin surface mount
packages with 16k or 32k of flash program memory (10k to 100k program
cycles), 1-2k of static ram, and 512-1024k eeprom (100k to 1000k program
cycles). They make denser versions in 64pin surface mount packages that
have more io pins, and external memory bus (sram only) as well as 'tiny'
chips in 28 pin skinny dip (no jtag interface on these though).

The rich development tools (easier than a software simulator and C
programming instead of assembler) make the AVR worth considering.
I don't work for Atmel, but I am using the Avr Mega chips at work,
and they ARE easy to use. The cost may be a little higher than
the pics, but only slightly so. Check out www.avrfreaks.org

My 50 cents worth.

The AmQRP club has a new DDS VFO kit available.

See http://www.amqrp.org

I think they just added it a few days ago.

I've been very happy with all the kits I have bought from AmQRP.

73 de KB9BVN


"VE3ELQ" wrote in message
...
Just acquired a Small Wonder Labs "White Mountain 75" QRP SSB
tranceiver. It works quite well as designed but would like to add a
DDS VFO with LCD frequency readout and re-package it all mainly for
PSK use. Looking for plans with PCB patterns and any hex code for a
suitable DDS VFO, or alternatively a VCO stabilizer with freq readout.
Googling turned up a few articles but not a package that I can build
myself from scratch not a kit job. Any pointers greatly appreciated.

VE3ELQ Nigel In Embrun Ontario

You have to see DL4JAL dds. I modify original pcb for using dil or smd
oscilator and 3,3v regulator and 7pole lpf.I use there a ad9851 and 160MHz
oscilator (wit ad9850 there is a 125MHz smd oscilator).I made seweral pcb
and now I try to made a separetly dds module and controler unit which use
an atmel at89S52. one frien of mine modifing soft for controlling an
ad9857 (14bit d/a converter).
Nice description is from VU3CNS.
I can send for those who are interesting a pcb printout and source
Vy 73's from Zibi

You have to see DL4JAL dds. I modify original pcb for using dil or smd
oscilator and 3,3v regulator and 7pole lpf.I use there a ad9851 and 160MHz
oscilator (wit ad9850 there is a 125MHz smd oscilator).I made seweral pcb
and now I try to made a separetly dds module and controler unit which use
an atmel at89S52. one frien of mine modifing soft for controlling an
ad9857 (14bit d/a converter).
Nice description is from VU3CNS.
I can send for those who are interesting a pcb printout and source
Vy 73's from Zibi

Zibi,
I saw Daniel, YO8RGJ's DDS on RADIOAMATOR.RO along with your comment
on that page. I am interested in the plans. Please send to
(without the ***).

Tnx,
Ted KX4OM

On Fri, 10 Dec 2004 04:54:35 -0500, "sp7ewl" wrote:

You have to see DL4JAL dds. I modify original pcb for using dil or smd
oscilator and 3,3v regulator and 7pole lpf.I use there a ad9851 and 160MHz
oscilator (wit ad9850 there is a 125MHz smd oscilator).I made seweral pcb
and now I try to made a separetly dds module and controler unit which use
an atmel at89S52. one frien of mine modifing soft for controlling an
ad9857 (14bit d/a converter).
Nice description is from VU3CNS.
I can send for those who are interesting a pcb printout and source
Vy 73's from Zibi

Witam.
Czy mozesz mi tez przeslac ? Z adresu email wykasuj wyraz "wytnij"
lub wez adres z callbook'a.

--
73
sq5izx