Stereo Memory Man w/ Hazarai mod?

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.

Re: Stereo Memory Man w/ Hazarai mod?

Postby 88mark » 06 Jan 2012, 15:04

DWBH wrote:You don't solder the transistors to that pad where it says R41/R42, you solder them directly on the encoder.

Actually, I don't know what's the value of those resistors, but if they're not big you probably could solder. I don't know, just checking. Solder directly on the encoder, just in case.



Hey DWBH, Thnx again for the answers!

Made another scematic. It would be really great if you could take a last critical look (especially at the wireing of those switches), and confirm that its the right way to solder. If it's not, feel free to edit the picture if you'd like to.
mod.png


Thnx!
You do not have the required permissions to view the files attached to this post.
88mark
 
Posts: 11
Joined: 18 Dec 2011, 21:47
Has thanked: 3 times
Have thanks: 0 time

Re: Stereo Memory Man w/ Hazarai mod?

Postby dodgypete » 06 Jan 2012, 23:18

I'm a bit late on this one :lol:

Your pull up resistors on the 2 inputs are wrong. You are correct in putting the resistors from the inputs to +5v, but your switches should be connected directly to the inputs.
If you wire it up like the drawing, the switches will pull the +5v supply to ground :shock:

The jack I used gets its GND from the enclosure, hence only 2 wires.

The GND for the arduino board goes directly to the centre of the 9v power jack.

I used the arduino pro because I had it lying around. I'm now using attiny chips for projects. I haven't got around to writing new code this project yet though.

For this message the author dodgypete has received thanks:
88mark (07 Jan 2012, 14:44)
dodgypete
 
Posts: 11
Joined: 07 Jun 2009, 01:39
Location: Christchurch, New Zealand
Has thanked: 0 time
Have thanks: 7 times

Re: Stereo Memory Man w/ Hazarai mod?

Postby 88mark » 07 Jan 2012, 14:59

Thnx Dodgypete! :thumbsup
I think i have the final scematic right now :)
mod.jpg

would be great if someone could confirm that it's correct this way :lol:


dodgypete wrote:I'm a bit late on this one :lol:

Your pull up resistors on the 2 inputs are wrong. You are correct in putting the resistors from the inputs to +5v, but your switches should be connected directly to the inputs.
If you wire it up like the drawing, the switches will pull the +5v supply to ground :shock:

Ok, so then it's like as on the scematic, right?

But, just for my curiousity, i don't understand what happens. there is 5v (or a little lower cause of the resistor) on the inputs, then i press the footswitch. and the voltage is still on the inputs, as well as it goes to ground through the switches. so I can't understand what changes to the inputs, when pressing the switch.. I'm a little confused here :scratch: :)
You do not have the required permissions to view the files attached to this post.
88mark
 
Posts: 11
Joined: 18 Dec 2011, 21:47
Has thanked: 3 times
Have thanks: 0 time

Re: Stereo Memory Man w/ Hazarai mod?

Postby DWBH » 07 Jan 2012, 16:44

Open this link:
http://www.falstad.com/circuit/#%24+1+5 ... +1+true%0A

When the footswitch isn't pressed, the input is always HIGH. When it's pressed, the input pin on the arduino goes LOW.

For this message the author DWBH has received thanks:
88mark (07 Jan 2012, 20:51)
DWBH
Cap Cooler
 
Posts: 505
Joined: 24 Aug 2007, 17:26
Location: portugal
Has thanked: 14 times
Have thanks: 4 times

Re: Stereo Memory Man w/ Hazarai mod?

Postby 88mark » 07 Jan 2012, 20:49

DWBH wrote:Open this link:
http://www.falstad.com/circuit/#%24+1+5 ... +1+true%0A

When the footswitch isn't pressed, the input is always HIGH. When it's pressed, the input pin on the arduino goes LOW.


huh? but that's not how dodgypete connected his board, is it?
this one is from the scematic I posted yesterday.

So, which scematic is right in your opinion, the last one i posted (like dodgypete said) or the one before that?
88mark
 
Posts: 11
Joined: 18 Dec 2011, 21:47
Has thanked: 3 times
Have thanks: 0 time

Re: Stereo Memory Man w/ Hazarai mod?

Postby 88mark » 07 Jan 2012, 20:51

BTW, I ordered some of the parts today. So I will be starting soldering soon. That would not be possible without your help, so thnx a lot!!!
88mark
 
Posts: 11
Joined: 18 Dec 2011, 21:47
Has thanked: 3 times
Have thanks: 0 time

Re: Stereo Memory Man w/ Hazarai mod?

Postby dodgypete » 07 Jan 2012, 21:45

88mark wrote:
DWBH wrote:When the footswitch isn't pressed, the input is always HIGH. When it's pressed, the input pin on the arduino goes LOW.


huh? but that's not how dodgypete connected his board, is it?
this one is from the scematic I posted yesterday.

So, which scematic is right in your opinion, the last one i posted (like dodgypete said) or the one before that?


That is exactly how I connected it.
dodgypete
 
Posts: 11
Joined: 07 Jun 2009, 01:39
Location: Christchurch, New Zealand
Has thanked: 0 time
Have thanks: 7 times

Re: Stereo Memory Man w/ Hazarai mod?

Postby 88mark » 08 Jan 2012, 00:51

dodgypete wrote:
88mark wrote:
DWBH wrote:When the footswitch isn't pressed, the input is always HIGH. When it's pressed, the input pin on the arduino goes LOW.


huh? but that's not how dodgypete connected his board, is it?
this one is from the scematic I posted yesterday.

So, which scematic is right in your opinion, the last one i posted (like dodgypete said) or the one before that?


That is exactly how I connected it.



aaaah, I got it (or at least, I think so.. ;) ).. The arduino is at the right of the scematic in the simulator, not at the top, true?

Thnx for the drawing DWBH.
88mark
 
Posts: 11
Joined: 18 Dec 2011, 21:47
Has thanked: 3 times
Have thanks: 0 time

EHX Stereo Memory Man Hazarai - Volume Drop Mod w/Pics

Postby cookieshoes » 11 Nov 2014, 00:42

Hi all,

I found these pics online of a mod for the volume drop on an EHX Stereo Memory Man with Hazarai.

Pics are from this site: http://www.vertexeffects.com/blog/tom-buk-pedalboard

I had reached out to the builder regarding the mod some time ago but was told that the mod isn't currently offered.
(BTW, I'm familiar with the recent discussions regarding this builder. For the thread here I'm just looking for any help with this mod, thanks.)

Anyone have any idea how this mod is being done? I see boards for the AMZ Op Amp and V Dub in there.

Can anyone steer me towards how to do the same, or a similar mod? Getting ahold of the AMZ boards is easy enough, just not sure how they are being used here (dual Op Amp makes sense, but not sure about the V Dub board). Anything else that could fit in there that would do the trick?

Image

Image
cookieshoes
 
Posts: 3
Joined: 14 Oct 2012, 18:13
Has thanked: 1 time
Have thanks: 0 time

Re: EHX Stereo Memory Man Hazarai - Volume Drop Mod w/Pics

Postby cookieshoes » 25 Nov 2014, 00:50

Bump.

Anybody know what function the V-DUB board is serving in the above pics?
cookieshoes
 
Posts: 3
Joined: 14 Oct 2012, 18:13
Has thanked: 1 time
Have thanks: 0 time

Re: Stereo Memory Man w/ Hazarai mod?

Postby dodgypete » 07 Mar 2018, 10:09

As requested here are the missing photos:

Image

Image

Image
You do not have the required permissions to view the files attached to this post.

For this message the author dodgypete has received thanks:
imemine (11 Mar 2018, 22:16)
dodgypete
 
Posts: 11
Joined: 07 Jun 2009, 01:39
Location: Christchurch, New Zealand
Has thanked: 0 time
Have thanks: 7 times

Re: Stereo Memory Man w/ Hazarai mod?

Postby imemine » 11 Mar 2018, 22:23

Hi. Thanks @dodgypete for the pictures above and thanks to everyone for the useful info on this thread. I tried this mod and it works! However, I have a problem: whenever I use the encoder (not everytime, but often) the mod stops working and I need to move the encoder again and again until it suddenly works again. Does it happen also to you?
imemine
 
Posts: 1
Joined: 06 Mar 2018, 08:02
Has thanked: 1 time
Have thanks: 0 time

Re: Stereo Memory Man w/ Hazarai mod?

Postby dodgypete » 08 Apr 2018, 10:06

Occasionally I have had trouble if the encoder is between steps (probably bumped when I've been setting up/putting away my pedal board).

If the encoder is sitting in one of the notches the mod always works for me.

When the encoder is between positions it will be pulling to ground, effectively shunting the transistors.
dodgypete
 
Posts: 11
Joined: 07 Jun 2009, 01:39
Location: Christchurch, New Zealand
Has thanked: 0 time
Have thanks: 7 times

Previous

Return to Modern Stompbox Effects (1975 - ...)

Who is online

Users browsing this forum: kingmafw, ramonmaruko, tp000841 and 14 guests