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Here are some pictures of the Wyllie Moonrock. I started trying to reverse this. There are some pictures over at TheGearPage, here: http://www.thegearpage.net/board/showth ... st18405704

Here are some images I made in photoshop.

This picture tries to show the top, which hopefully aligns with the next image:


Here's the bottom:


Then I drew in all of the PCB connections, red circles, and tried to fill in values for parts.

Looks like the builder burned most the pads of the PCB in the process of building it.

You should look up Wyllie. He's the original DIY stompbox guy. He had been making these things for years. He makes the enclosures himself. I get impression he lived in a shack in the woods with a dog and solder iron.

Supposedly all of the circuits are original. Sadly he passed away recently so you can't get these any more. Look up some sound samples of the moonrock it's got a unique sound.

Here's what I have so far.

I'll presume it's some sort of Octavia type effect.

Not sure, could be, it's got the transformer. But, it looks like only one side of the transformer is in use as an inductor. It's got a lot of diode pairs.

Here's my latest layout. A lot of the values are still missing and there's bound to be some errors still. I'm trying to put together a rough schematic from what's here. I'm hoping that will reveal something.

soggybag wrote:Not sure, could be, it's got the transformer. But, it looks like only one side of the transformer is in use as an inductor. It's got a lot of diode pairs.

Here's my latest layout. A lot of the values are still missing and there's bound to be some errors still. I'm trying to put together a rough schematic from what's here. I'm hoping that will reveal something.

[ Image ]

Oh whacky; I didn't notice it left one side unused.

Here's what I get out of the one i have using soggy's very helpful trace diagram as a guideline (I had some errors when I jotted it down originally but that made it a lot easier to sort out).



I dunno, I'm no comprehensive circuit historian myself, but it doesn't look familiar to me.

It's not an octavia or ampeg scrambler as it had been thought to be for a long time.

Pretty odd circuit.

V_____ wrote:Here's what I get out of the one i have using soggy's very helpful trace diagram as a guideline (I had some errors when I jotted it down originally but that made it a lot easier to sort out).

[ Image ]

I dunno, I'm no comprehensive circuit historian myself, but it doesn't look familiar to me.

It's not an octavia or ampeg scrambler as it had been thought to be for a long time.

Pretty odd circuit.

Look at C6/R11 again. I'd suspect the connection is more like C7/R13, and C6 doesn't connect directly to ground (at least, I don't see it at a quick glance). It would make more sense that way, since you'd get (sort of) balanced outputs from Q2 and an octave effect from D5/6 acting as a rectifier. Then for some reason there's D7 and D8, which essentially drops out the parts of the signal below the threshold voltage, which is usually used to get rid of noise, but in this case is just weird. Adjustment should adjust the timbre/gain/octave stuff simultaneously as drawn. I dunno. The whole thing is weird. I'm pretty confident in the first half (the only thing is the input cap in the original is reversed), as I traced that part. The rest is too obscured in the pictures for me to bother.

Yeah, you're right I think. I think I made a mistake on the the 21k resistor. It goes to ground and then the other end is the one connected to the cap and the diode

I think c3 goes to ground.

soggybag wrote:I think c3 goes to ground.

No, I traced that part, it doesn't go to ground. It should, but it also really shouldn't matter all that much since it blocks DC. Any steady reference should behave the same. I suspect it may have been easier to route it there on the board than to ground.

EDIT: V, I meant R10 should go directly to ground, and the only the positive end of the cap should connect to R10. Haven't actually traced that part yet, but if that's how it is in the actual pedal, it really doesn't make any sense.

mmolteratx wrote:

soggybag wrote:I think c3 goes to ground.

No, I traced that part, it doesn't go to ground. It should, but it also really shouldn't matter all that much since it blocks DC. Any steady reference should behave the same. I suspect it may have been easier to route it there on the board than to ground.

EDIT: V, I meant R10 should go directly to ground, and the only the positive end of the cap should connect to R10. Haven't actually traced that part yet, but if that's how it is in the actual pedal, it really doesn't make any sense.

You're right. I realized I made a boner a minute ago. That section seems to go like this.

V_____ wrote:

mmolteratx wrote:

soggybag wrote:I think c3 goes to ground.

No, I traced that part, it doesn't go to ground. It should, but it also really shouldn't matter all that much since it blocks DC. Any steady reference should behave the same. I suspect it may have been easier to route it there on the board than to ground.

EDIT: V, I meant R10 should go directly to ground, and the only the positive end of the cap should connect to R10. Haven't actually traced that part yet, but if that's how it is in the actual pedal, it really doesn't make any sense.

You're right. I realized I made a boner a minute ago. That section seems to go like this.

[ Image ]

Yea, that's what I got. Here's the sections I've done.

Slightly different. I'll have to double check to see if the 1M attaches before or after the coupling cap from Q2 output. The diodes that go to Q3 are both in the same direction on mine, for sure, though. Not sure if that's true of both pedal examples. Maybe mine has a mistake.

V_____ wrote:Slightly different. I'll have to double check to see if the 1M attaches before or after the coupling cap from Q2 output. The diodes that go to Q3 are both in the same direction on mine, for sure, though. Not sure if that's true of both pedal examples. Maybe mine has a mistake.

I dunno. That's the part I couldn't see, so I put it like that, since two in parallel wouldn't really do anything. Whichever had the lower forward voltage drop would conduct, and the other one would do nothing.

mmolteratx wrote:

V_____ wrote:Slightly different. I'll have to double check to see if the 1M attaches before or after the coupling cap from Q2 output. The diodes that go to Q3 are both in the same direction on mine, for sure, though. Not sure if that's true of both pedal examples. Maybe mine has a mistake.

I dunno. That's the part I couldn't see, so I put it like that, since two in parallel wouldn't really do anything. Whichever had the lower forward voltage drop would conduct, and the other one would do nothing.

Yeah. It seems wrong to me, but that's what's in mine. Maybe Glenn was daydreaming that day.

Looks like the 1M resistor on the bottom does connect to C on Q2 rather than after the coupling cap.

Here the link to the transformer datasheet:

http://www.mouser.com/ds/2/449/XC-600127-202003.pdf

The transformer is applied as coil with about 1.59 Henrys.

Transformer is TL018 - and not TL012:

Grubgoat wrote: Transformer is green in the middle, one side has a big "P" on it, other side nothing. On the metal sides, one has "TL018-R", and....and after great potential peril to the pedal, (seriously he's got this thing wound tight), 1019S I think.

http://www.thegearpage.net/board/showpo ... stcount=31

tube-exorcist wrote:Transformer is TL018 - and not TL012:

Grubgoat wrote: Transformer is green in the middle, one side has a big "P" on it, other side nothing. On the metal sides, one has "TL018-R", and....and after great potential peril to the pedal, (seriously he's got this thing wound tight), 1019S I think.

http://www.thegearpage.net/board/showpo ... stcount=31

For this reason the inductance is 1.11 Henrys.