Mxr phase 100 passes signal no effect

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Mxr phase 100 passes signal no effect

strassercaster
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hello i finished the Saviss layout for the phase 100 . I really took my time with this one but its not working. it passes signal on and off but doesnt phase. it does actually sound out of phase but no pulse or throb . i took pictures and i used a red sharpy to show cuts on both sides. The hardest parts to see in the pictures are the Vactrols i have checked them a half dozen times. Something bothers me about the D2 power suplly for the bottom right and middle vactrol there is a jumper between them but a cut on the layout is this right? The top vactrol is getting 9v right from leg 8 of the top middle tl072. dont all of them need 9volts?there is a cut under the diaginal 100k resistor abover the trimmer how are these getting power and is it supposed to be 9volts?
top left Tl072
1 4.79v
2 4.79
3 4.33
4 0
5 4.76
6 4.78
7 4.77
8 9.58

top middle
1 4.79
2 4.78
3 4.76
4 0
5 4.72
6 4.78
7 4.86
8 9.58

top right
1 4.65
2 4.78
3 4.72
4  0
5 4.72
6 4.84
7 4.74
8 9.57

bottom left
1 4.60
2 4.77
3 4.75
4 0
5 varies 4.51-5.07
6 varies 4.69-5.07
7 varies 3.90-5.96
8 9.57

bottom middle
1 4.64
2 4.77
3 4.75
4 0
5 4.72
6 4.69
7 4.48
8 9.57

bottom right
1 4.51
2 4.74
3 4.71
4 0
5 4.72
6 4.86
7 4.49
8 9.57

transistors
top left
e varies 4.1-4.57
b 4.60-5.11
c 9.57

top middle
e .58
b .96
c .40

top right
e 0
b .40
c .40

bottom right

e 0
b .59
c .77

vactrol top  green
d2
top leg 9.56
d2 bottom leg 0
vactrol top 4.76
vactrol middlie 4.76
vactrol bottom 4.76


vactrol middle purple
d2
top leg 0
d2 bottom 0. definitely one of my problems
vactrol purple
top leg 4.72
middle 4.76
bottom 4.71

vactrol bot right blue
d2 top right 0.42
d2 bot left 0
vactrol blue
top right 4.71
middle leg 4.76
bottom left leg 0

so i have some problems with transtors and vactrols.i have checked for bridges several times and ran a knife several times.different readings on the led/d2 section on all three vactrols . I assume 9 volts needs to be on one of the diode legs correct? or should it be the 4.7 volts ? i think i have a few issues here.transistors seem low d2 d3 not getting power.
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Re: Mxr phase 100 passes signal no effect

strassercaster
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Re: Mxr phase 100 passes signal no effect

strassercaster
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Re: Mxr phase 100 passes signal no effect

ξεναγος νεκροπολης
In reply to this post by strassercaster
hi mate!
here is the schem from where i've drew the layout.


http://www.generalguitargadgets.com/pdf/ggg_p100_sc.pdf

this shows those "D2s" in series just like i've put them.i just saw your comment in the other original threat. hope that new vactrol will solve your problem!


good luck!!!!
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Re: Mxr phase 100 passes signal no effect

strassercaster
yep its working .i was getting a sever squeal with switch 1 on .i changed the 15k. to 30 k on the top row r1.it stopped so i went down to a 22k still good. did yours squeal? ill try going down as far as i can till i get the squeal back . its pretty cool . mine seems mild. its working best with the trimmer dimmed. do you think a bigger trimmer would produce a more phase ? its not as prominant as i would like. plus switch 2 doesnt seem to have much of a change at slower settings. is this normal? thanks Sav
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Re: Mxr phase 100 passes signal no effect

ξεναγος νεκροπολης
hi mate!
i'm glad you''ve somehow made this work.
first of all i didn't build this.i just drew the layout, so you're the first that will verify this layout!
a bigger trimmer may help giving more phase. try a 50k.
you also have a badly damaged-burned-melted 10nf cap at the right of the second tl072.that might explain the squeal.  

ic's socket looks a bit melted too and i don't know if that happened while you had the ic in the socket.if you did have the ic in, then try to replace that too with a new one. (but i doubt that ic is bad cause your voltages look good.)  

about the switches now. the original has a 2p4p rotary just like alex has on his layout.if you have one use that. i did it with 2 spdt cause i 've never worked on a rotary before and i didn't have one to examine how it's working.

hope i helped and that you'll end up with a perfect build
good luck again!
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Re: Mxr phase 100 passes signal no effect

strassercaster
dooooh verified. had the first vactrol backwords . squealled with switch one on changed 15k on top row too 22k fixed that . very nice effect. i dont notice much of a change its subtle( maybe you could look at my build pics and see if i did a mistake )with switch 2 switch one definitely makes a major change. ill check some more. taking a break after tomorrow. august was a good month. i built a tonepad small stone.2 phase 90s with script and univibe mods a phase 100  a phase 45 a rub a dub deluxe , tweaked my pinnacle  and boss ce-2 and made a son of hyde(marshall shred master with 8 value changes)got to take a break . i miss playing chops are down and cut into family time. i have a prescription electronics clean octave blend  COB to box tomorrow and a rub a dub to builD and im takking the rest of the month off for work rest and family.Sav you rock bro. thanks for everything. glad i could verify this monster build. i already have a dirt baby and harbinor one. next month i am doing both on stripboard.i might do a coiple of more gain pedals as well. i still havent built a fuzz face im stocked with almost 10 kinds of germanium transistors in the 50-120 hfe range. .still wish one of you wizards would stripboard a small stone . i should probably do a bad stone i love phase pedals

 .. I am posting a request for a peavey classic vt phase circuit. peavey also used the ca3094 ota chips. ca3080 should work.  My second amp on the early 80'S before i could find or afford my marshalls was the 1979 peavy classic Vt it had a built in phaser that was very prominet thick but had teo knobs color and rate . the amp had a great clean channel the gain channel was horrible imho ha ha.your a phase guy too arent you?it sure would be cool to box it. im going to find the preamp schematic i found it a few weeks ago but forgot to save the link. it looks alot like the small stone maybe we could mod a small stone and change the values idk . if i didnt have 3 kids id just buy one for 300 off craigslist but i would love to build one.what do you think?