Lovepedal - Vibe/Magicboy  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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Manfred
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Post by Manfred »

Here the traced schematic, the revised PCB layout will follow later.
LovePedalVibeSchematicV1.jpg
Last edited by Manfred on 01 Nov 2021, 08:47, edited 1 time in total.

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Post by Manfred »

The type 1N5230 for the diode D1 is only an assumption of me it could be also a 1N5231 with Uz = 5.1V.
Can you measure the voltage at the diode?
LovePedalVibeSchematicV2.jpg
LovePedalVibeLayout.JPG
Ready to print PDF files:
LovePedalVibePCBComponentsSide.pdf
(23.03 KiB) Downloaded 97 times
LovePedalVibePCBSolderSide.pdf
(4.94 KiB) Downloaded 86 times
SprintLayout6 file:
LovePedalVibe.zip
(25.93 KiB) Downloaded 84 times
Last edited by Manfred on 31 Oct 2021, 23:54, edited 2 times in total.

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DjPsychic
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Post by DjPsychic »

I will measure as soon as I get the chance.

Thank you for all the great work!

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Intripped
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Post by Intripped »

you're missing a 10k resistor that in the layout is just above C7,
and R13 should be 1M and not 140R

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Post by Manfred »

Intripped wrote: 31 Oct 2021, 22:54 you're missing a 10k resistor that in the layout is just above C7,
and R13 should be 1M and not 140R
Thanks for the closer look and the hints. :thumbsup
I overlooked the 10k resistor because there are no solder pads for it.
Four eyes see more than two.
I also changed the resistor R13 to 1 Megohm.
I have replaced all the documents in the post above with the revised ones.

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Post by DjPsychic »

Manfred wrote: 01 Nov 2021, 00:00
Intripped wrote: 31 Oct 2021, 22:54 you're missing a 10k resistor that in the layout is just above C7,
and R13 should be 1M and not 140R
Thanks for the closer look and the hints. :thumbsup
I overlooked the 10k resistor because there are no solder pads for it.
Four eyes see more than two.
I also changed the resistor R13 to 1 Megohm.
I have replaced all the documents in the post above with the revised ones.
Oops that would be my fault! First time trace

I measure 4v @ the diode

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Intripped
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Post by Intripped »

So, these are the main differences from the MXR Phase 45:

MXR / LOVEPEDAL

R4 10K / 22K
C2 50n / 10n
C3 50n / 100n
C5 50n / 100n
C7 50n / 150n
BIAS trim 250K / 50K
SPEED C(B) 500K / B 100K
out resistor* 150k / (missing)

*out resistor to ground

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Post by Intripped »

actually the BIAS trim should be 250K, not 50K. i think there's a little error in your schematic, Manfred.

and still seems strange to me that there isn't any resitor to ground on the output; could be an off-board component, maybe?

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Post by Intripped »

i've found some pics of unit #10 from reverb.com, and on this unit the output resistor is present.
You can see it in the first pic, at the bottom-left of the PCB, very close to the red output capacitor (C7 - 150n, referring to Manfred's schematic)
Attachments
jbh40tl94jdcs9wssdjm.webp
miyqjwh7hhibcuce6ns6.webp
p5j8uqslhztkcdpafopl.webp

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DjPsychic
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Post by DjPsychic »

Intripped wrote: 01 Nov 2021, 15:05 So, these are the main differences from the MXR Phase 45:

MXR / LOVEPEDAL

R4 10K / 22K
C2 50n / 10n
C3 50n / 100n
C5 50n / 100n
C7 50n / 150n
BIAS trim 250K / 50K
SPEED C(B) 500K / B 100K
out resistor* 150k / (missing)

*out resistor to ground
Looking at the MXR Phase 45 schematic I’m seeing 47n not 50n for those cap values. Are you rounding up?

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Intripped
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Post by Intripped »

I looked at one schematic I downloaded from... I don't remember, and it had these values.
Anyway, it doesn't make any difference, considering capacitors tolerances.

PS: It was a schematic from ampage.org, that I downloaded from elektrotanya

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Manfred
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Post by Manfred »

Intripped wrote: 08 Nov 2021, 18:04 actually the BIAS trim should be 250K, not 50K. i think there's a little error in your schematic, Manfred.

and still seems strange to me that there isn't any resitor to ground on the output; could be an off-board component, maybe?
Thanks, you are right!
I have cut the reworked image of the component side for my template to the size of the board and cut off the "2" at the value.
Here are the revised documents.
LovePedalVibeLayout.JPG
LovePedalVibeSchematicV2.jpg
Ready to print PDF-files:
LovePedalVibePCBComponentsSide.pdf
(22.86 KiB) Downloaded 90 times
LovePedalVibePCBSolderSide.pdf
(4.84 KiB) Downloaded 92 times
SprintLayout 6.0 file:
LovePedalVibe3.zip
(25.18 KiB) Downloaded 88 times

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DjPsychic
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Post by DjPsychic »

Intripped wrote: 01 Nov 2021, 15:05 So, these are the main differences from the MXR Phase 45:

MXR / LOVEPEDAL

R4 10K / 22K
C2 50n / 10n
C3 50n / 100n
C5 50n / 100n
C7 50n / 150n
BIAS trim 250K / 50K
SPEED C(B) 500K / B 100K
out resistor* 150k / (missing)

*out resistor to ground
Finally got another chance to look at the project. Just a note, the numbers on the MXR schematic don’t match the the Lovepedal numbers you’ve listed here. I’m looking at the schematic GGG btw

http://www.generalguitargadgets.com/pdf/ggg_p45_sc.pdf

Trying to figure out which parts I need to swap on the phase 45 I already built. Trying to avoid building again :blackeye

http://tagboardeffects.blogspot.com/201 ... se-45.html

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Post by DjPsychic »

Intripped wrote: 01 Nov 2021, 15:05 So, these are the main differences from the MXR Phase 45:

MXR / LOVEPEDAL

R4 10K / 22K
C2 50n / 10n
C3 50n / 100n
C5 50n / 100n
C7 50n / 150n
BIAS trim 250K / 50K
SPEED C(B) 500K / B 100K
out resistor* 150k / (missing)

*out resistor to ground
Finally got another chance to look at the project. Just a note, the numbers on the MXR schematic don’t match the the Lovepedal numbers you’ve listed here. I’m looking at the schematic GGG btw


http://www.generalguitargadgets.com/pdf/ggg_p45_sc.pdf

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Post by Intripped »

Components numbering is referred to Manfred's schematic/layout (the only one that you can actually see in this page)

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Post by Intripped »

Referring to GGG schematic:
R4 22k
C2 10n
C3 100n
C8 100n
C4 150n
SPEED B100k
R11 - this is the out res to ground - your choice

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