9V Electric Mistress retrofit with MN3007

[Thomeeque]

OK, I'm a goose  

Obviously my build really hates power supplies like the 1-Spot.  Although the EM was running off a battery, my LM386 test amp was using the 1-Spot for its power supply.  Today I switched back to my normal amp with the EM running off a battery and it's nearly silent except for the most extreme settings.

At least I've got a workaround now.  I'll see if one of my mates has a transformer based power supply and whether that's any quieter.  I might have to finally invest in a proper isolated power supply.

Hi John!

I'm glad you have found cause of the issue - I know how this kind of issues can get frustrating!

Extreme settings are noisier principially, so you are probably OK now.

About your PSU: is it this one



? Well, normally I would simply say get rid of it (I'd never choose switching PSU for pedals), but Visual Sound = R.G. and R.G. usually knows what he's doing - maybe you could try to consult with him? There still may be some simple solution how to make your pedal and your PSU good friends

Good luck, T.

Btw. thanks for the clock readings! - was it maximum where you could get without dropouts?

[Just1More]

Hi John!

I'm glad you have found cause of the issue - I know how this kind of issues can get frustrating!

Extreme settings are noisier principially, so you are probably OK now.

About your PSU: is it this one



? Well, normally I would simply say get rid of it (I'd never choose switching PSU for pedals), but Visual Sound = R.G. and R.G. usually knows what he's doing - maybe you could try to consult with him? There still may be some simple solution how to make your pedal and your PSU good friends

Good luck, T.

Btw. thanks for the clock readings! - was it maximum where you could get without dropouts?

Yeah, that's the one.  I have similar noise issues with another switching PSU (Diago Powerstation) with this pedal.  Despite some bad press about switching PSUs, with my setup I've never had an issue before.  I know some pedals are more susceptible than others - may the EM just doesn't get on well with them.

I could probably squeeze a little more out of the clock.  The minimum setting went up to about 84kHz or 86kHz before I started getting dropouts, but I'm not sure what the maximum was.  I'm happy to have another fiddle with it if you want me to take another reading - especially given the amount of assistance you've provided me with this build. Thanks again.

[Scruffie]

Dunno if anyone's interested but I re-drew the SAD1024 TZF Board to use the MN3007 and this seemed as good as any place to add it, Entirely Untested & Unchecked -

[Marcos Camara]

Friends,
in my arose the following problems:
The guitar signal does not go along with it;
Presented something like a whistle and a siren unbearable;
Stirring the pot I saw clearly that they work by changing noises and whistle;
I noticed the flanger effect manifests itself, but along with noise and whistle. But nothing of the sound of the guitar show.
Reviewed every little thing, every little thing and nothing.
Does anyone have an idea of what??

Note: I used BC557 and BC549 (reversed) as equivalent.

[StephenGiles]

What is the advantage of this 4049 inverter buffer circuit. Why not 3 and 3??

[Thomeeque]

What is the advantage of this 4049 inverter buffer circuit. Why not 3 and 3??

I believe I was inspired by your post here I was sure that if it's good for ADA it should be good for EM as well..

Btw. would you have these two documents stored by any chance please (www.film-tech.com seems to be down now), I'd like to see them if possible:

http://www.film-tech.com/warehouse/manuals/KINTEKKT24.pdf
http://www.film-tech.com/warehouse/manuals/SMARTSR330.pdf

Thanks, T.

Dunno if anyone's interested but I re-drew the SAD1024 TZF Board..

Hi! This board is an overkill (needlessly complicated clock mainly, LPF maybe too) - I'll try to draw something lighter, if I'll have a minute.

T.

[Thomeeque]

double-post, sorry

[Scruffie]

Dunno if anyone's interested but I re-drew the SAD1024 TZF Board..

Hi! This board is an overkill (needlessly complicated clock mainly, LPF maybe too) - I'll try to draw something lighter, if I'll have a minute.

T.

Ah, that would explain this quote from the original thread

I know there are some things that could be simplyfied, but hey... it works Wink

I had no idea what was needed or not and just copied it straight from the TZF Thread Schematic & Converted it, i'm glad it can be simplified though, if you do get a minute that'd be great to see what you come up with  

[oldschoolanalog]

Hi! This board is an overkill (needlessly complicated clock mainly...)

Can't this be done w/just a 4046, 4049, and "associated components"?

(...LPF maybe too)

The LPF seems simple & functional enough. If it ain't broke...

- I'll try to draw something lighter, if I'll have a minute.T.

As always, your efforts are appreciated! 

[StephenGiles]

What is the advantage of this 4049 inverter buffer circuit. Why not 3 and 3??

I believe I was inspired by your post here I was sure that if it's good for ADA it should be good for EM as well..

Btw. would you have these two documents stored by any chance please (www.film-tech.com seems to be down now), I'd like to see them if possible:

http://www.film-tech.com/warehouse/manuals/KINTEKKT24.pdf
http://www.film-tech.com/warehouse/manuals/SMARTSR330.pdf

Thanks, T.

Dunno if anyone's interested but I re-drew the SAD1024 TZF Board..

Hi! This board is an overkill (needlessly complicated clock mainly, LPF maybe too) - I'll try to draw something lighter, if I'll have a minute.

T.

Ah yes, thanks for the reminder!

I'll have a look for those documents.

[Just1More]

Well, I finally got mine finished - or so I thought.  Once it was all boxed up I found yet another problem.  There's an annoying ticking sound which is pretty obvious with both the effect engaged and when bypassed.  I hadn't seen this on my test rig - only since it was boxed up.

Speed varies as the Rate control is adjusted so I'm guessing it's LFO related.  So far I've done a quick bit of poking around with the daughter-board and the input, output and flange/matrix switch wiring with no change to the ticking.  Looks like yet more debugging ahead of me 

I'll keep working on it, but any advice would be welcome...

Here's some pics anyway:

[Thomeeque]

Well, I finally got mine finished - or so I thought.  Once it was all boxed up I found yet another problem.  There's an annoying ticking sound which is pretty obvious with both the effect engaged and when bypassed.  I hadn't seen this on my test rig - only since it was boxed up.

Nice build, congats!

I've had same issue, solution is relatively simple - LFO section (including speed pot wiring) works (thanks to present square wave signal of big amplitude) as a pretty strong transmitter of electro-magnetic pulses, signal path (including in/out jacks) is pretty sensitive receiver. Solution is to keep these parts electro-magnetically isolated. Either you try to keep them far enough from each other or to use electro-magnetical shield between them. In your case second way is probably more suitable. Have a piece of metal plate (e.g. from empty beer can) and wrap it around LFO section, don't forget to connect it conductively to the ground. That should help.

Good luck, T.

[Just1More]

Nice build, congats!

I've had same issue, solution is relatively simple - LFO section (including speed pot wiring) works (thanks to present square wave signal of big amplitude) as a pretty strong transmitter of electro-magnetic pulses, signal path (including in/out jacks) is pretty sensitive receiver. Solution is to keep these parts electro-magnetically isolated. Either you try to keep them far enough from each other or to use electro-magnetical shield between them. In your case second way is probably more suitable. Have a piece of metal plate (e.g. from empty beer can) and wrap it around LFO section, don't forget to connect it conductively to the ground. That should help.

Good luck, T.

Thanks Tomas.  My next move was to try some grounded aluminium foil shielding, so thanks for validating this idea 

[DiamondDog]

If anybody is interested in the changes done to make this work let me know.
If not, I won't waste my time posting info that is of no interest.

Please post- I'm very interested in this.

[oldschoolanalog]

Page 2, reply 26. This thread.

Reference material:
9V EM PCB, schematic & layout: http://www.aronnelson.com/DIYFiles/up/9V_Mistress_project_file_v11_update.pdf
3007 retrofit board thread: http://www.diystompboxes.com/smfforum/index.php?topic=78270.0
Good reading:
http://www.diystompboxes.com/smfforum/index.php?topic=63044.0
http://www.diystompboxes.com/smfforum/index.php?topic=34607.0
First, parts not used/installed:R23,R19,R11,R12,,D1,D2,C5,C9. Changes: new value & explanation in (parenthesis): R5(jumper), R17(47K, improved bias range), C19(10pf, This was done to raise the max clock f), R38(15K, As you raise the max clock f, the low f goes up w/it. This restored the low clock f), C14(Added 3n3 in parallel w/the existing 2n2 [5n5 total], the regen was way too "thin sounding". This "fattened" things up a bit), The clock trim pot was wired as in the DELUXE EM schem. This gave a wider clock range. I put 47R in series w/R29, at their junction a 22uF cap was connected to GND. Also, 100n PS bypass caps were installed at every IC (3007 board also). These 2 things are there to provide a measure of "insurance", so to speak. Also, I was running short on certain parts, so for the retrofit board I used 22uF caps for C1,2,4 and I used 47R for both R1&5. Hookup of the retrofit board is fairly obvious. See photos, a few posts back (If you want more details, just ask! ) Just remember to DOUBLE THE CLOCK f's WHEN SETTING THIS UP. Double the BBD stages; double the clock f. Please feel free to ask Q's. Also, as I mentioned earlier, if anybody sees a way that this can be improved upon or done better; or; if anything is obviously incorrect, please say something. I feel this works and sounds as good, if not better than the EM's I have heard/owned in the past. Now who will be the first to try this?
Have Fun!
Dave

[Just1More]

Nice build, congats!

I've had same issue, solution is relatively simple - LFO section (including speed pot wiring) works (thanks to present square wave signal of big amplitude) as a pretty strong transmitter of electro-magnetic pulses, signal path (including in/out jacks) is pretty sensitive receiver. Solution is to keep these parts electro-magnetically isolated. Either you try to keep them far enough from each other or to use electro-magnetical shield between them. In your case second way is probably more suitable. Have a piece of metal plate (e.g. from empty beer can) and wrap it around LFO section, don't forget to connect it conductively to the ground. That should help.

Good luck, T.

Thanks Tomas.  My next move was to try some grounded aluminium foil shielding, so thanks for validating this idea 

Tried this out with some grounded kitchen foil - works like a charm  .  I'll try and put a more permanent solution together on the weekend.

[SpufuZ]

Hello

I've made a new layout joining both Gaussmarkov's layout and daughter-board by Tomas (Tomeeque).
It's already tested and working. I Used the mods suggested by Dave W.(oldschoolanalog).
Schematics later (I'm lazy now  )

http://www.4shared.com/document/wPcCxA3H/Mistress_9v_MN3007.html

I hope you like it !

The link doesn´t work anymore!?
Have you completed the schematics?

//David

[Scruffie]

Hello

I've made a new layout joining both Gaussmarkov's layout and daughter-board by Tomas (Tomeeque).
It's already tested and working. I Used the mods suggested by Dave W.(oldschoolanalog).
Schematics later (I'm lazy now  )

http://www.4shared.com/document/wPcCxA3H/Mistress_9v_MN3007.html

I hope you like it !

The link doesn´t work anymore!?
Have you completed the schematics?

//David

Works fine for me.

Any news on the TZF Board Thomeeque? 

[SpufuZ]

Yes!
Now it worked.
The schematic would be nice now! 

Are the two layouts in the PDF on page 2 identical?

[jorge r]

Are the two layouts in the PDF on page 2 identical?

Yes they are!