Fulltone - Supa-Trem

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gtrplaya101
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Post by gtrplaya101 »

oh wow yep that a vactrol for sure. I was being dumb and looking for a LDR.
+1 on the wiring photo.
And a view of the whole top without the top part of the board cut off.

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Post by Barcode »

gtrplaya101 wrote:oh wow yep that a vactrol for sure. I was being dumb and looking for a LDR.
+1 on the wiring photo.
And a view of the whole top without the top part of the board cut off.
the only thing at the edge of the board (besides wires, which i will get a diagram worked up for later tonight) is one resistor, which you can make out at the top of my labelled pic. also, if you look at ag's gut shots he posted, that edge is clearly visible.

ag, were you able to read the bands on the metal film resistors?

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Post by analogguru »

They are all 100k. The resistor labelled 68k appears to be 6k8. The same with the 15k which appears to be 1k5 and the resistor left beside the LF442 is a 8k2.

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Post by Barcode »

analogguru wrote:They are all 100k. The resistor labelled 68k appears to be 6k8. The same with the 15k which appears to be 1k5 and the resistor left beside the LF442 is a 8k2.

analogguru
yeah, if you save the pic and blow it up, i was using a MUCH smaller font than i thought, those values should reflect what is on my labels if you look REAL close :)

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Post by Barcode »

This should be all we need now:
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also, i could use help on what substitute opamps could be used. i think a standard tl072 would work in place of LF351, but i don't know about the rest.

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Post by Barcode »

bump...

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Post by Barcode »

hmm, no replies? I have researched in the trembulator thread and found that the tlo72 will work in place of the lf442, and tl071 in place of the other two. I'm very close to a functional clone, i just need:

the value of that small bead capacitor

i need to know how to put the 10k trim in place. according to the board, i can't find how the holes match up with the trim pot, and there are only two that i see?!?!

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Post by analogguru »

Sorry.... but sometimes I have to earn some money too.
So the ceramic cap is somthing Mystical, there must be printed something on it (e.g. 472, 223 or 104) which can´t be seen in the pictures, but the value is not really critical.
The trimmer is in the feedback looop and therefore connected with one outer leg to the output and the slider to the inverting input (or viceversa) of the AD 711.

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Post by Barcode »

analogguru wrote:Sorry.... but sometimes I have to earn some money too.
So the ceramic cap is somthing Mystical, there must be printed something on it (e.g. 472, 223 or 104) which can´t be seen in the pictures, but the value is not really critical.
The trimmer is in the feedback looop and therefore connected with one outer leg to the output and the slider to the inverting input (or viceversa) of the AD 711.

analogguru
hmm, makes sense. I guess he just breaks off one leg or bends it underneath to put the trim in. i think i might adjust my board to accomodate the trim a little better. i'll try a 220 pF in that cap spot and give it a go.

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Post by Barcode »

Okay, worked up a new layout slightly based on fuller's. The values are what i used when i made my clone, and the pads are there for all the different switches, but i didn't put them in my build. The rate pot totally covers all usable speeds for me, so no double/half switch needed, and I used an external pot for the hard/soft trim pot instead of installing the switch. I haven't test this specific layout yet, but i've node checked and it isn't far off the original, so it should be good. funny thing is i haven't had time to work up a schem, so i'm hoping ag or someone can finish out the project with a schem.
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Post by Danch »

Hi
Just to notice you, there is no connection on pin7 IC3 on your pcb/layout. The schematic is the same as Demeter Tremulator, some different resistor values.

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Post by Barcode »

Danch wrote:Hi
Just to notice you, there is no connection on pin7 IC3 on your pcb/layout. The schematic is the same as Demeter Tremulator, some different resistor values.
good eye, it should connect to the nearby trace of the positive side of C4. I'll fix later tonight.

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Post by Barcode »

layout has been corrected. i also noticed that i had the status LED at the wrong pad. If you used the old layout, you will need to solder a jumper from pin 7 of IC3 to the positive leg of C4. otherwise, if you use this one, the only unlabeled is the pad for the rate LED, which is the pas just below the IC on the left at the bottom of the board.

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Post by Barcode »

anybody else want to throw a second set of eyes on my layout? It should work from wht i can tell, but my clone is not functioning. strange... can't seem to find the issue either.

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Post by ShortScaleMike »

It would be easier to check your layout if you knocked up a schematic.

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Post by Barcode »

ShortScaleMike wrote:It would be easier to check your layout if you knocked up a schematic.
good point. the schem (with the exception of actual values) should be basically the same as baja trembulator:
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Post by ShortScaleMike »

Seeing as you have the actual values, can you not just knock up a Supa Trem schematic for the community?

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Post by Barcode »

ShortScaleMike wrote:Seeing as you have the actual values, can you not just knock up a Supa Trem schematic for the community?
yes, just hadn't had a chance to. I wanted to get a complete working project together. But perhaps you are right, I think I am putting the cart before the horse. I will see if i can whip something up.

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gtrplaya101
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Post by gtrplaya101 »

Im excited about seeing a working version of this pedal, any chance of a correct schematic?

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Post by Barcode »

workng on it.

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