Adjustable sine wave generator circuit?

[haveyouseenhim]

Can someone point me in the direction of an adjustable sine wave generator layout/schematic? Ideally It would sweep the human audible range, but really anything with a nice sweep will work. I tried google and the search function but came up with nothing.

[LucifersTrip]

?

you can't you just screw with the resistors on those?

I built something like this for circuit bending, but don't remember doing any adjusting
http://talkingelectronics.com/projects/50%20-%20555%20Circuits/images/555-Osc-1.gif

http://www.next.gr/uploads/135-8825.png
http://www.next.gr/oscillators/sine-wave/adjustable-sine-wave-audio-oscillator-l12335.html

http://www.next.gr/uploads/135-11557.png
http://www.next.gr/oscillators/sine-wave/sine-wave-generator-circuit-l15014.html

[petey twofinger]

please forgive me for butting in here an hijacking ...

i had built the q nd test osc. , i believe that is a sine wave , no ?

any way i akways have it really near my work area and it dawned on me that i would like to tune it to get it close to 440 a or an E note as possible .

taht way i could use it to tune when i am changing strings or messing around , like an old pitch pipe idea , just something to get me in the ball park , not perfect .

i tried messing with the q n d osc resistors , and it did not work out ... i am actaully very intersted in this idea , using the q n d , i get sick of the same tone , and my neighbors prolly do too .

a sine out of a 555 chip , wow am i an unlearned soul . i had no idea that was possible .

going to keep an eye on this , please let me know if yall figer this out , thanks !

[haveyouseenhim]

i had built the q nd test osc. , i believe that is a sine wave , no ?

That's what spurred this thread. I saw yours and wanted an adjustable sine generator. Not just for testing. Maybe to run through some effects or just trying to shake my house down with some low frequencies

[Ronan]

Merlin (valve wizard) did a design for an adjustable sine wave gen I believe, in fact, here it is:
http://www.freewebs.com/valvewizard2/siggen.html

[haveyouseenhim]

Merlin (valve wizard) did a design for an adjustable sine wave gen I believe, in fact, here it is:
http://www.freewebs.com/valvewizard2/siggen.html

Beautiful...........thank you very much, that's exactly what I had in mind

[Seljer]

Heres another one that should put out pretty clean sinewaves, though you need a dual potentiometer for the frequency control

http://sound.westhost.com/project86.htm

[samhay]

You can build a pretty slick signal generator using an XR-2206 chip - see Fig 12 in the datasheet for a really nice sine wave: http://www.jaycar.com.au/images_uploaded/XR2206V1.PDF
The chips might be just about obsolete but can still be found for a few quid/dollars on ebay.

[Keppy]

I've made a sine wave VCO by adapting the one from the LM13600 datasheet. More components, but all are current production, and no dual pot.

[Kesh]

you can use your computer as a pretty good function generator if your sound card is good

visual analyser is good software for this

[Seljer]

you can use your computer as a pretty good function generator if your sound card is good

visual analyser is good software for this

Ground loops and noise issues are a problem though. I haven't tried any transformer isolation and such but I've got 40mVrms of 1Mhz signal in my computer's audio output

edit: thats on the front panel connector, the one on the back is a bit quieter (I should take my computer apart and make up a shielded cable for that connector ) but still, the ground loops don't help

[haveyouseenhim]

Ground loops and noise issues are a problem though. I haven't tried any transformer isolation and such but I've got 40mVrms of 1Mhz signal in my computer's audio output

Exactly. I can hear my computer 'thinking' through the speakers. I hate it

I'm starting to populate valve wizard's sine wave generator right now.

Thanks Ian

[Kesh]

like i say, you need a good sound card.

[haveyouseenhim]

like i say, you need a good sound card.

I have a decent soundblaster.

[Kesh]

was thinking home DAW stuff. and card was a misnomer as they're often external.

[haveyouseenhim]

I finished the sine generator earlier and have been having some fun with it. Shaking the house. Pissin off the neighborhood dogs. Breaking a handheld mirror in the next room. I guess it shook off of the cabinet. And that's really saying something since my house is on a solid concrete foundation 

[Ronan]

Did you do the Merlin one? That is the one I would do if I didn't have an old Kenwood sig gen.
Mike the Machine, there's no stopping you...

Even with a cheap multimeter, you can measure gain in a booster or opamp circuit, simply by measuring the AC voltage input (from the sig gen) and the AC output from the circuit. For example, if you have 100mV in, and 1.2V out, then its x 12 gain. If you keep increasing the input signal, but the output remains the same, or doesn't increase much, then the circuit is probably clipping i.e. square waving/distortion/maxed out. Most cheap meters measure up to 1kHz, or at least 400Hz, so make sure the test frequency is less than 1kHz. Some cheap meters will also read the frequency of the signal. Lots of fun.

[haveyouseenhim]

Did you do the Merlin one? That is the one I would do if I didn't have an old Kenwood sig gen.
Mike the Machine, there's no stopping you...

Even with a cheap multimeter, you can measure gain in a booster or opamp circuit, simply by measuring the AC voltage input (from the sig gen) and the AC output from the circuit. For example, if you have 100mV in, and 1.2V out, then its x 12 gain. If you keep increasing the input signal, but the output remains the same, or doesn't increase much, then the circuit is probably clipping i.e. square waving/distortion/maxed out. Most cheap meters measure up to 1kHz, or at least 400Hz, so make sure the test frequency is less than 1kHz. Some cheap meters will also read the frequency of the signal. Lots of fun.

Yep. I used Merlin's layout. I managed to get some etching done while everyone else was eating Christmas dinner. Pffft, Crohn's disease isn't all bad....While others are doing something totally pointless like eating, I can be changing the world with my projects

[haveyouseenhim]

[kingswayguitar]

dr who?!