Search found 15 matches

by smanq
23 Jun 2022, 12:43
Forum: Boutique Stompboxes dissected...
Topic: DSM & Humboldt Simplifier
Replies: 20
Views: 4390

Re: DSM & Humboldt Simplifier

Any news?
Looking at the posted image, I've completed presence & resonance stage with component values. I've also slightly redrawn the left part of the tube switching: when the 2 switches are open, the EL34 is selected.

Image
by smanq
03 Jul 2015, 07:27
Forum: Boutique Stompboxes dissected...
Topic: BJFE - Emerald Green Distortion Machine [traced]
Replies: 90
Views: 50008

Re: BJFE - Emerald Green Distortion Machine [traced]

OK, the schematics reflect the board layout. But if the A50K pot controls trebles, I confirm what I said before. If we connect the 4n7 cap to source, when the wipe is full CW, both first and last stages have a boost on high frequencies (exactly a low cut on first stage); when the pot is full CCW las...
by smanq
02 Jul 2015, 15:41
Forum: Boutique Stompboxes dissected...
Topic: BJFE - Emerald Green Distortion Machine [traced]
Replies: 90
Views: 50008

Re: BJFE - Emerald Green Distortion Machine [traced]

deep_intruder wrote:In my opinion there are two mistakes, the two caps: 1u and the 4n7 of the last fet, both must be wired to the drain and not to the source!
I think the 4n7 cap is right connected to the source (like on other BJF circuits), but the 1uf cap (the circuit output) must be connected to the drain.
by smanq
10 Feb 2014, 11:03
Forum: Boutique Stompboxes dissected...
Topic: Secretefx - Secret-1 STD overdrive [traced]
Replies: 31
Views: 17202

Re: Secretefx - Secret-1 STD overdrive [traced]

It's possible to bias a buffer in this way, but it's definitely the worse one, simply because it's higlhy hfe and temperature related. A classic 2 resistors partition from supply and ground it's more stable and it permits to use a wide range of transistors (wide range of hfe), without any relevant d...
by smanq
27 Jul 2013, 10:18
Forum: Boutique Stompboxes dissected...
Topic: HAO - Sole Pressure [traced]
Replies: 41
Views: 22586

Re: HAO - Sole Pressure [traced]

Very strange the choice of 100K resistor before the LEDs, I've never seen a such high value in this position.

For the pots, I think the Drive is C500K (rev log) and the Volume is A100K (log).
You can delete the other components from the schematics: they are for the switch.
by smanq
03 May 2010, 22:56
Forum: Boutique Stompboxes dissected...
Topic: Menatone - Blue Collar (guts)
Replies: 19
Views: 6151

Re: Menatone - Blue Collar (guts)

Some days ago I've repaired a recent Blue Collar for a friend: it's a bit different (in the output stage) from the schematics posted here. I've hand drawn the schematics, so I'll post it. This is the schematics I've hand drawn. There was a small circuit with a mosfet around supply, but this is out ...
by smanq
03 May 2010, 22:32
Forum: Boutique Stompboxes dissected...
Topic: Menatone - Blue Collar (guts)
Replies: 19
Views: 6151

Re: Menatone - Blue Collar (guts)

i dont have any .22 polarized caps??? Any ideas........? Just use non polarized caps there if you don't have the tantalum caps. Many will argue it won't make a difference to sound. Better yet socket them and then use what you have now and order the tantalums to try later. I have metal film .22's in...
by smanq
03 May 2010, 21:26
Forum: Boutique Stompboxes dissected...
Topic: Menatone - Blue Collar (guts)
Replies: 19
Views: 6151

Re: Menatone - Blue Collar (guts)

Some days ago I've repaired a recent Blue Collar for a friend: it's a bit different (in the output stage) from the schematics posted here.
I've hand drawn the schematics, so I'll post it.
by smanq
29 May 2008, 07:26
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Maxon - OD-808 (RI) 6 Transistors?
Replies: 14
Views: 14028

Re: Maxon - OD-808 (RI) 6 Transistors?

Noob question here. :) I have true bypassed several TS9's and TS808's but never a Maxon pedal. What do I need to remove to true bypass this? Anything? Can I just connect the in/out in the traditional true bypass configuration? I've done it removing R17, Q1 (you need to link drain and source with a ...
by smanq
14 May 2008, 09:23
Forum: Stuff Seen for Sale
Topic: PEDALMAN 818 OVERDRIVE PRO
Replies: 8
Views: 4308

Re: PEDALMAN 818 OVERDRIVE PRO

Fantastic!!!
I'm thinking to ask him a little discount.... :hmmm:
.... around 95% !!! :mrgreen: :mrgreen: :mrgreen:
by smanq
07 May 2008, 08:20
Forum: Boutique Stompboxes dissected...
Topic: HAO - Sole Pressure [traced]
Replies: 41
Views: 22586

Re: HAO - Sole Pressure [traced]

From some posts and what we can see from the guts, the schematics could be like this sp draft.jpg The supply filter seems a 100uF cap. I suppose the VR is half supply from classic 2 resistors and a filter cap (values?). Where are placed the 22K and 100K resistors we can see in photos? Please try to ...
by smanq
07 May 2008, 00:08
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Maxon - OD-808 (RI) 6 Transistors?
Replies: 14
Views: 14028

Re: Maxon - OD-808 (RI) 6 Transistors?

This is the schematics of the OD808 RI (sorry, it's hand drawn). Maxon OD808.jpg The switching circuit is in separate file. Maxon OD808 switching circuit.jpg Some notes: 1. The supply filter cap is a 100uF/16V, so you can use 9 or 12V supply; for 18V you need to replace it with a 25V cap 2. The outp...
by smanq
06 May 2008, 10:34
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Maxon - OD-808 (RI) 6 Transistors?
Replies: 14
Views: 14028

Re: Maxon - OD-808 (RI) 6 Transistors?

The RI schematics is different: there is 1 op-amp (JRC4558D) and 3 transistors for buffering, 2 FETs and a transistor for the switching.
The transistors are all C1815.
by smanq
05 May 2008, 13:44
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Maxon - OD-808 (RI) 6 Transistors?
Replies: 14
Views: 14028

Re: Maxon - OD-808 (RI) 6 Transistors?

Yes, the differences are uniquely on the switching circuit: the SPDT switch changes the status of the 2 FETs without a F/F circuit.
The schematics can be useful for TB mod of this stompbox (I've just done it for a friend).
by smanq
04 May 2008, 22:08
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Maxon - OD-808 (RI) 6 Transistors?
Replies: 14
Views: 14028

Re: Maxon - OD-808 (RI) 6 Transistors?

I'm drawing the schematics for this version, I'll post it ASAP.