4x16 Ch PIC controller for DDS. ANY FREQUENCY = NO MORE XTALS!

[Stretchyman]

At Last.....

Well it's taken a couple of years but finally it's ready!

So you've all seen those DDS boards from China, right?

eBay item number; 291550491443

They've been on eBay for over 2 years now and no-one can work out why they're so cheap as the AD9850 part alone is $20!

Basically it's a chip that can generate any frequency up to 60MHz with incredible accuracy.

Problem is you have to talk to it in digits so have to have the ability to program and build an interface.

Between myself and a colleague we've produced a PCB which will store 64 frequencies and will come ready programmed with all the usual U.S and Euro 6 Meg freqs + anymore you request.

Sure there are plenty of other kits out there that use this DDS board but they all tune, have a display and none have channels or are simple to implement.

Just supply 3.3V or 5V and by using a HEX switch choose one of 16 channels. There are 4 banks so this can be a 4 way sw or just hard wire if you ONLY need 16 Ch.

Have attached a picture.

Take a look.

Stretchy

[Stretchyman]

OK have settled on 2 banks of 16 Channels, 1 U.S. Bank and 1 Euro.

+ 2 more banks of 16Ch with M.W, 90m and ham freqs (any of these can be changed on request)

So I can offer a complete solution with DDS board and PIC.

Complete and programmed with these Frequencies;

EURO    US  
6200   6850
6205   6855
6210   6875
6240   6880
6245   6890
6250   6900
6260   6910
6265   6920
6270   6925
6280   6930
6285   6935
6290   6940
6300   6950
6380   6955
6390   6960
6400   6980

++++++


1476   5317
1850   7070
1885   7143
1933   7175
1945   7290
1963   7295
1972   8000
1985   11595
3229   12000
3395   13000
3615   14000
3625   14286
3705   18150
3825   21285
3870   21425
3875   10000


Output is 1V p-p sine or 5V square.

 

[EliteData]

Output is 1V p-p sine or 5V square.

RF output ?

[Stretchyman]

Yes!  Definitely!

 

What I mean to say is that I'm confused with your question.

It's a signal generator that generates RF at the frequencies quoted.

Yes it outputs RF, what else could it do......I'm still very confused by your question?

Am I missing something, perhaps?

Please let me know!

Str.

[Stretchyman]

Crazy as I've never sold one of these?

I don't get it?

Anyway will be 'incorporating' one into my High Power TX.

KW anyone?



Str.

[redhat]

I think a more appealing interface would be 5 rotary switches to select ANY frequency.  Kinda annoying not being able to see what frequency your dialing up.

+-RH

[Stretchyman]

5 switches when you can do it with one?

It's addressing memory locations (BCD HEX)

That and the switches would cost 5 times as much as the circuit!

But Hey if I fit 5 switches and put it in great big box I may sell some!

16 is enough for most anyway, just make a list and stick it to TX, Simple.

 

[redhat]

I have seen situations where moving a few KHz makes all the difference, and if where you want to move doesn't fall on one of the channels, that is pretty inconvenient.  It also kinda stinks that you have to know what address the frequency you want is stored in, so in the field you would need a list.  A display would make things much easier, and you could use a rotary encoder with push function to dial up any frequency you need and be able to see it before hitting the air.  This is the way most of the VFO kits work.

Just a thought...

+-RH

[Stretchyman]

Thanks Bud, but it's not a VFO and it's not a kit, adding a display, no way, that's something completely different and there's 101 of those out there already.

Again would bump up the cost x10

This is a direct replacement for Xtals, if you want to move 1KHz, well program +1KHz into a memory location.

As stated they're no longer for sale and will be part of a high power generator with PWM, you'll preselect freq before tx with a DIP sw, again a cost saving measure!

Str.

[ChrisSmolinski]

RedHat: Maybe something like this? http://www.ebay.com/itm/DDS-Signal-Generator-0-55MHz-for-Digital-HAM-Radio-SSB6-1-Transceiver-VFO-SSB-/171928942747

[Stretchyman]

Just the job!

However it's the size of the planet!

There's loads of these things around.

I wanted something ultra simple def without a display.

Best if it's got an Si570 from SiLABS but any DDS is OK, the 9850 is the poorest (No PLL etc) but those cheapy Chinese things make it a No Brainer.

sdrkits do a nice Si570 setup;

http://www.sdr-kits.net/Webshop/index.php?cPath=6&osCsid=af56qnfohdlf7l7qe8p9hs2c64

[redhat]

I'm not really a fan of the Si570 stuff, no way to externally discipline it, and they do drift a little I've found.

+-RH