Homebrew 3 Channel Pure SIN Generator ( 0 ... 60MHz )

[Yucca]

Here's a photo of the approx layout of the device on a verocard.

At the back is two 5V 1A PSUs, serial linked for 10V 1A.

Down the left is two caps, these give the unit a little time after power is unplugged, in that time it can easily save whole system state to permanent memory.

Behind the microcontroller and screen you can see 3 x DIL16 sockets, These I will plug the DDS modules into (using only one row in each socket). If I have to have the modules horizontal to accomodate a clock buscard then I will have to use 90DEG sil pins and do that.

The micro itself will have SIL headers soldered at 90deg to the board and it will also plug into the vero card.

The whole card will go into some box on standoffs with a cutout for the screen. Jogwheel on the right and output BNC connectors on the left.

Input sample conditioning circuit will be built on the front left of the verocard.

[otto]

Hello all,

@Yucca

it doesnt matter if you use square waves or sine waves: A TPU will convert squares in sines. Automatically. This automatically means that "mother earth" is doing it.

A verocard!!!

Now I will tell you something.

A oscillator builded on a verocard is something like .....  its worthless!!!

I have 1 of my 3 oscillators years ago builded on such a verocard. Better NOT to use such an oscillator to pulse coils.

Yes, you get the signals, but they are not worth a cent.

And build the oscillator as simple as possible. @dankie said the same? Yes, he is right.

With such a simple oscillator maybe you can discover anomalies in your coils that will blow you from your chair and your coils will be soooo "happy" you cant imagine. Coils are "happy" when they are blown. And then your happy because then you know that you have SOMETHING.

Otto

[Peterae]

otto
The oscillators are not built on vero they are prebuilt professionally, he is only using vero for the digital side of things, he's trying to make it so an ameature can build it without having to buy or make their own pcb's.

If you goto page 1 you can see the link for buying the DDS modules.
and yes the DDS module use a filter on the output to make the stepped DDS output pure sine.

@Yucca
i am not famillar with the atmel processor, but with the pic the EEPROM can be written to many millions of time without failure, so over use is unlikely, you could do a write verify read and if an error occurs switch to bank 2.

Again on the pic you have a built in function called brownout, which monitors the voltage rail and at a preset voltage level adjustable with some pics, you get an interrupt to save your code.

Another scheme i have used before is to save 1 byte of your parameters every second if it's different to your eeprom, this way the eeprom is gradually updated when the power is on, and then do a final check as a power down situation occurs, this way you can have little or no eeprom to write during a power down situation.

Peter

[MasterPlaster]

KISS

[otto]

Hello all,

again and as mentioned, if you want to work on coils like an amateur without any successes you can use profi builded oscillators.

But if you are working on coils to discover "something" than you have to build oscillators with PCBs and then you may have something good.

Ever thought about capacitances in oscillators? Between every single part in an oscillator?? Capacitances in picofarads.

O yes, they are not important. But maybe something weird could "jump out" from such not important capacitances.

It was just a thought so forget it.

Otto