Skyripper wiring questions

[bside2234]

Does the diode by the expression loop have to go a certain way? It seems to be backwards on the pads in the diagram.

I am just waiting for the enclosure to come in the mail and I will wire this thing up and see what I get. I was going to try to stuff it in a smaller enclosure I already have but I decided that might be a bad idea.

I was bored today and was looking at the SR PCB and thought I might be able to make it smaller. If I got it right, I shrunk it down by 1/2" horizontally and vertically. I may try to use it on my second build of this pedal to see if I can fit it into the smaller enclosure I already have.

[John Lyons]

Yes, the diode has to go a certain way. And it is right on the layout.
It might look reversed because of how I made the layout and the wire pads.

The layout could be a little smaller but not a whole lot. The pots take up more space than the board anyway.

John

[bside2234]

OK. So I am all wired up and am putting the Trannies in there sockets. I got the FF kit from Smallbear and have no idea what legs are what on the 3AX31C's. I can't seem to find a datasheet on the either. The legs seem to be in a triangular configuration but there are no markings on them (I may be blind but I don't see any).
Also, the two trimpots that are right next to each other, am I adjusting both of those for the one transistor? What does the top one affect?

I also put the 3AX31C with the higher gain in Q4.

[joegagan]

the two trimpots on the collector of q4 are to set two different bias presets on q4 collector.

one is the standard -4.5v of a regular fuzzface, the other is a very starved -1v, which gives some of the coolest rippytones.

it is a bit of a balancing act , but you must switch back and forth on s4 till you get almost exactly those readings. the -1v is particularly important, the -4,5v less critical.

i think every pnp germ tranny i have had has the same pinout. just follow any ge trans pinout sheet ,should be fine.
yes,the higher gain trans should be at q4

[bside2234]

Thanks Joe. I had the GE transistors in the right way. They just didn't have any markings on them so I wanted to make sure.

Well, just looking over everything to make sure everything looks good. and I am pretty sure I wired the Buffer dual gang pot backwards. Also, I may have the battery clip wired backwards. I hooked up the red of the clip to lug 1&2 of the Bias pot and the black of the clip to -9v on the board. I say this because the led's only light up when I reverse them.  I have the led's in the right way. Cathode on the switches and anodes to the pcb.

[joegagan]

the buffer diagram seems to be correct on john's layout, just doublecheck and correct if necessary.
check your pm on the batt hookup.
be sure you jumper the exp loop pads if you aren't using jacks in the loop!

[John Lyons]

I made a mistake on the layout concerning the LEDs. They should be wired anode to the switch (not cathode as it says) I always confuse that and just wire then the way it makes the light come on!
With the Transistors you just put them in the way the pattern is on the layout, forms a triangle as the pads are. Are you using sockets?

Make sure to read the instructions on the schematic as far as biasing. They are detailed and tell you just how to do it. It's a little confusing because you need to flip the switch and check the bias voltage back and fourth but you'll get there.

Question Joe: With the silicon transistors in Q1 and 3 does the bias shift with heat or is it stable since those transistors are silicon instead of germanium?

John

[joegagan]

hard to recall, my experiments with all that are a long time ago now.
all the data regarding hybrid fuzzfaces applies, tho.
a vaguely recall all of my fuzzes got a lot more temp stable when Q1 of the two FF trannies were si (Q3 and Q4 in skyrip)

thanks again for the great layout and diagrams

[bside2234]

Ok,
The LED's are working now.
I have the bias pot turned up all the way. I am measuring a max of -1.03 on the collector of Q2 (it won't go any higher) and at Q4 I am measuring -1v with switch 4 open and 4.20v with switch 4 closed. 4.20v is as high as I can get it.

[Austin73]

I've been watching this thread for a little while now, as I'm really interested in making one of these eventually. Nice that Joe has jumped in to help too.

Just a quick question to John, I looked on your site as Bill is using your layout but I don't see one. Is it not for public consumption, or do you make boards for them?

Any help in the matter greatly appreciated .

Cheers as always

Aus

[joegagan]

hey bill, your voltages sound pretty good actually. this is close enough to find out if it is basically working. if you can substitute a 20k or 25k trimpot for the 10k trimpot closest to the collector, this should get your -4.5v setting closer to spec. just make sure to rebalance both to get the proper -1v in s4's other setting.

anyway, to see if you are basically in the ballpark,  turn all the rip settings off, rangemaster off, set the tone on the fuzz full up, on the 4.5 v voltage setting, play your guitar. it should sound like a good fuzzface with no splatting etc. this is the first step to making sure it will do all the other stuff it's supposed to do.

aus, nice to see you jump in.

[bside2234]

I thought the voltage at Q2 is supposed to be 6.8 to 7.1v?

Did the settings you recommended Joe and I get a very weak (low signal) fuzz face sound.

So here is where I am at.
1. The bias control lowers the voltage but also makes the LED's fade out. It that supposed to happen? Seeing as they are hooked up to the same 9v source I suppose it is.

2. What exactly does the boost/cut switch do. Right now I get nothing in one position and my weak signal in the other. This switch also seems to affect the biasing of Q4.

3. The buffer switch basically does what the boost/cut switch does right now. It basically lets the weak signal through one way and not the other. It is possible I wired it up sideways. I need to look into that more.

4. I do need to run wires from ground to sleeve on the this right?

[joegagan]

I thought the voltage at Q2 is supposed to be 6.8 to 7.1v?

that is correct

Did the settings you recommended Joe and I get a very weak (low signal) fuzz face sound.

think of it as two pedals. disconnect the rangemaster portion in listen to it by itself and check voltages. ditto on the fuzz section. do both of these tests completely bypasssing your buffer pot wiring to verify that each section sounds and biases correctly.

So here is where I am at.
1. The bias control lowers the voltage but also makes the LED's fade out. It that supposed to happen? Seeing as they are hooked up to the same 9v source I suppose it is.

correct, in most normal settings you should still be able to see them. if this is a problem you will have to pull your 9v power for the led pre bias pot. ( incl. whatever resistor you use to bring the led voltage into spec)

2. What exactly does the boost/cut switch do. Right now I get nothing in one position and my weak signal in the other. This switch also seems to affect the biasing of Q4.

, i should have made that clear in the biasing instructions on the orig schem. i assumed that people biaisng it would be familiar with the fuzzface -4.5v and recognize that the normal fuzzface mode is with no feedback diode in circuit (as it would be with s5 connected). so this is correct, your bias will change when s5 is engaged ( connected)

3. The buffer switch basically does what the boost/cut switch does right now. It basically lets the weak signal through one way and not the other. It is possible I wired it up sideways. I need to look into that more.

until you are sure the buffer pot is wired correctly we don't know what's up with that.


4. I do need to run wires from ground to sleeve on the this right?
yes, jacks are grounded at sleeve if that is what you are asking

[bside2234]

Thanks. I will keep playing with it and see what I can do.

I guess the first thing is to figure out why I can't get more than -1.03v at Q2. I am supposed to be measuring it from collector to ground right?

I like the LED dimming thing. It kinda tells me where I am at on the bias pot.