Ring Modulator kit

[RaceDriver205]

For those who are interested I found a great ring modulator kit.
I couldnt find a MC1495(and who can), and trying to build a circuit for the MC1496 without PCB router software etc, is an absolute pain (esp when u dont know if your circuit will even work).
The kit is available from Jaycar electronics, which i assume is only an australian company, and is called the "sound like a dalek" project (not designed with guitars in mind).
The modification for converting it to a stompbox is to remove the electret microphone and its 10k resistor, and connect suitable sockets for the input and output.
U get the same telephone-tone noises etc as the Maestro, plus if you plug in a mike u make dalek/star wars robot noises, n if you plug in a bass u get an awesome sound that seems like some kind of synthy bass overdrive (i dunno how to explain it) on low notes.
Interesting thing is it doesnt use a special IC - it actually implements a full balanced modulator circuit.
(Price is AUS$20 + post). (catno KJ8228 + layout&intructions (separate) KJ8229)

lol, i should be a salesman.

[Paul Perry (Frostwave)]

Jaycar are very keen to sell to the USA (or indeed anywhere!).

[octafish]

What is carrier suppresion like on this device?
Also does it look like it would be capable of accepting an external carrier mod?

[brett]

Hi.
This kit is for a balanced modulator, which is slightly different to a ring modulator.
It also has some really terrible characteristics, not the least of which is the noise that the 555 throws onto the power lines.
A couple of years ago I designed a balanced modulator that also uses a dual op-amp for phase splitting, but uses a CMOS 555 (TLC555), and has some other advantages as a guitar effect.  That effect was the Modulatron.  It's viewable at my web-site.

I recently re-designed it, using a simpler phase splitter, and eliminating the output buffer.  But I haven't yet tested this new version.  Hopefully, it will work better than ever.  If so, it'll be a few weeks before I test and post it.

Concerning carrier bleed-through... the Modulatron has discernable, but not a high level of bleed through.  Less than the Thing Modulator, for example.

cheers

[RaceDriver205]

Really? I found the carrier noise indecernable (on this model), and i reckon a noise gate at very low threshold would be enough to remove it completely (seriously, i had to put my ear right next to the speaker). Keeping the signal input level high helps.
I do hope when i put it with other effects it wont make them whistle. Ill have to get the switch to cut the power connection as well as bypass the effect if this is so.
I personally dont think it would be capable of accepting an ext carrier mod. It makes the classic/standard wierded out dial tone noises, and more tastefull "robot distortion" noises if you play the right notes at the right carrier frequency. (Got that effect, whats next etc.) If you want the "real deal" with sine/triangle wave carrier input (which is unlikey to cover up its wierdness), i think youll need a different design. (smallbear should really buy some mc1495s and tda1097s).
I reckon when ive built (n made work) everything else, ill build the "light metal" "active" ring modulator.

[brett]

Hi.
You're right about not being able to modulate the signal with this circuit - it's NOT a ring modulator.  All it can do is shift the phase of the input signal at a certain frequency.  The CD4066 is a switch that is just turned on and off by square wave comming out of the 555.  While in theory you could use a different waveform (ie not the 555's square wave), but the switches are either on or off, and no smooth transitions are possible.

I agree that carrier noise is at least several dB less than other simple modulators.  However, it still annoys me.  (Though I live in a quiet area in the country, and at the moment I can hear my dog snoring outside.)

cheers