Author Topic: 9V Electric Mistress project file done (Bernardduur??)  (Read 39317 times)

0 Members and 1 Guest are viewing this topic.

markusw

9V Electric Mistress project file done (Bernardduur??)
« on: April 24, 2006, 12:10:48 PM »
Since I wanted to give Flangers a try and there isn't yet a layout for the 9V Mistress I decided to do one.
Basically, I just traced the original layout from Berdarddur's pics as I wanted to be as sure as possible to get it working  (I read a lot about problems with clock noise...etc).



Although I believe that everything is fine I still have to check it.



Some Qs and comments:

* Is it a good idea to have the gnd connections as a "ground plane" ??

* from Bernard's pics it seems that the two 130k resistors at the input were replaced with a 5.6k and a 1M (maybe 2M) to vref. Actually there was another 5.6k added from the input jack to the input cap. I suppose this is the mod performed by EH on Bernard's unit to avoid (reduce) the volume drop of the unit.
Bernard: it would be great if you could check if the input cap is still 39n as in the schem.

* From the pics it also seems as if the 200 ohm resistor between gnd and ps gnd is not used. Instead ps gnd is connected directly gnd.

* Also it seems that there is an additional electrolytic added directly to the ps jack. The two other ps electrolytics seem to be quite large (and of the same size). Maybe they were changed to larger values. At least the 100 seems to have the same value as the 220 (Bernard?)


* The funny thing is that I can't find the output wire although I really studied the pics very carefully. The pad that is connected to the 510R, the 8k2 and the 13k  is not connected to any wire. Any ideas??

* Do you think it's OK to replace the 82n near the output with a 100n???

* In the schem by Francisco a 1M-C (this is reverse log??) is indicated for Rate, In the deluxe version at ggg a 1M log. Considering that the LFO section is more or less the same: which one gives the better response?? OK, I think I solved this one ;)

* Edit: one more: Would it make sense to add two resistors for gain control to the input buffer stage (to compensate for the volume drop when in true bypass??)

Thanks to Francisco, Stephen and Bernard for posting the schems and pics, btw!!

Comments on how to improve the layout are highly appreciated!

Once I've checked everything I'll post the complete stuff.

Thanks for your help in advance!

Markus

« Last Edit: May 07, 2006, 12:48:12 PM by markusw »

BDuguay

Re: 9V Electric Mistress layout
« Reply #1 on: April 24, 2006, 01:00:47 PM »
Cool!
Thanks for putting that together. I hopes everything checks out okay.
B.
My band
http://www.myspace.com/newtloomer
Country music is broken. We'll fix it.
Authorized builder for B.Y.O.C.
www.buildyourownclone.com

psst

Re: 9V Electric Mistress layout
« Reply #2 on: April 25, 2006, 04:02:33 AM »
Nice!
I'll keep an eye on this post...

markusw

Re: 9V Electric Mistress layout
« Reply #3 on: April 26, 2006, 01:44:02 AM »
Nice!
I'll keep an eye on this post...

Your comments on this unit were a reason too to give it a try :)

Berdardduur: could you do me a big favour and check on your unit were the output wire is connected to. I suppose this should be possible without removing the PCB.
Thanks a lot in advance!!!

Markus


Bernardduur

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #4 on: April 26, 2006, 04:52:01 AM »
I'll check in a while!
Am learning something new every day here

SquareLight | MySpace account

markusw

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #5 on: April 26, 2006, 05:35:38 AM »
I'll check in a while!

Cool! Thanks a lot!


markusw

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #6 on: April 27, 2006, 01:32:37 PM »
Quote
Would it make sense to add two resistors for gain control to the input buffer stage (to compensate for the volume drop when in true bypass??)

OK. I think I also solved this one. The headroom of BBDs is rather limited compared to e.g. opamps. Therefore, increasing the gain definitely doesn't make any sense. This limited headroom is also the reason for the 130k/130k voltage divider at the input. Isn't it??

 Maybe I can squeeze in a gain stage at the output...

Markus

Bernardduur

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #7 on: April 27, 2006, 01:51:37 PM »
Let me see.

- input cap = .039 f
- the PS filtering cap = 220 f; without it you hear a lot of clock noise
- the output is the glob of goo next to the middle trimpot (on the backside). I guess I desoldered it when I took the pic
Am learning something new every day here

SquareLight | MySpace account

markusw

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #8 on: April 27, 2006, 02:07:45 PM »
Let me see.

- input cap = .039 f
- the PS filtering cap = 220 f; without it you hear a lot of clock noise
- the output is the glob of goo next to the middle trimpot (on the backside). I guess I desoldered it when I took the pic

Thanks :)

Now everything is more or less clear!

BTW, how does it sound with bass??  Are there any issues with distortion (e.g. when used with an active bass)??

Markus

Bernardduur

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #9 on: April 27, 2006, 02:44:29 PM »
Hmmmm, good question; never used it with bass.

Give me 5 minutes ;)

OK, it sounds GREAT with bass. The unit sounds, to my ears, even better on bass then on guitar...... wow, this is a great discovery for me. No issues whatsoever with distortion or anything, altough I must say that I kinda lose distortion when the unit is on. I tried with both my P as J bass and with my Flipster preamp before it.

Nice! Now it is a shame I have it on my guitar board, have no place on my bass board and pretty much got used to my Small Clone (heavily modded) that I don't need it on bass.
« Last Edit: April 27, 2006, 02:58:15 PM by Bernardduur »
Am learning something new every day here

SquareLight | MySpace account

darryl

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #10 on: April 27, 2006, 02:59:02 PM »
Is this the same 9v Mistress as the one at Tonepad, I just finished building that one per the schematic and it is ticking like crazy. I have added some more filtering does'nt seem to do anything. It is Flanging just with a horrible tick, I have done the search on this and found a little advice. The strange thing is it so loud its like a pop at slow speeds that is. I hope this is OK to post this to your topic, if not I start a new one.

Thanks
Darryl

markusw

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #11 on: April 27, 2006, 04:05:18 PM »
Bernard, thanks for your review! Seems I'm gonna like it :)

darryl, since it might well be that I have to deal with the same issues as you it's very OK for me ;)

How close is your layout to the original one??

Markus

Bernardduur

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #12 on: April 27, 2006, 04:13:43 PM »
Is this the same 9v Mistress as the one at Tonepad, I just finished building that one per the schematic and it is ticking like crazy. I have added some more filtering does'nt seem to do anything. It is Flanging just with a horrible tick, I have done the search on this and found a little advice. The strange thing is it so loud its like a pop at slow speeds that is. I hope this is OK to post this to your topic, if not I start a new one.

Thanks
Darryl

Yes, it is..... mine is real (found it in a dumpster) ;) I have no pop or any noise at all as long as you keep the color pot low
Am learning something new every day here

SquareLight | MySpace account

darryl

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #13 on: April 27, 2006, 04:55:10 PM »
I just layed it out on my own, just follow the schematic, did use two boards though one for LFO, and one for audio. So no real layout just go for it sometimes, tried a number of fixes nothing yet. I will note that in the Filter matrix mode it seems to work alright, it shuts off at the end of the pot turn. Lfo seems to stop to at the slow end of the resistence. I will keep working let you know.

Darryl

markusw

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #14 on: May 05, 2006, 02:45:22 PM »
Good news!

It works ... and it sounds wonderful :) Just connected it the first time to my power supply and it immediately worked. Clock noise is not present. However, I replaced the two ps caps with ridiculously large ones (1000 and 470). I'm very exited :) Tomorrow, I will check clock speed and also whether there is a volume drop. Will be interesting to see because I included the mods from Bernardduur's pics.
Hopefully, I can complete the project file this weekend. Thanks to EH for a terrific pedal!

Regards,

Markus
« Last Edit: May 06, 2006, 09:19:17 AM by markusw »

nelson

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #15 on: May 05, 2006, 02:54:31 PM »
Excellent!

 ;D

Good going Markus!
My project site
Winner of Mar 2009 FX-X

markusw

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #16 on: May 06, 2006, 09:34:59 AM »
Just checked the clock frequencies.

With the clock trim at 50% (lugs 1 and 3 are wired like in Stephen's schem), the rate pot at 0% and the range pot at 100% the clock frequ range is from ~29kHz to ~212kHz, with the trim at 0 or 100% the range is from ~172kHz to ~880kHz (measured after the flip flop).

If my calcs are correct this would give a flanging freq range (lowest notch) of 56-416 Hz (clock trim at 50%) and 335 Hz to 3437 Hz. Please correct me if I'm wrong.

Just out of curiosity:  Bernardduur could you do me another huge favour and measure the clock frequency range on your unit at pin 1 or 2 of the 4013 (with rate pot at 0% and range pot at 100%) ???? Thanks a lot in advance.


I believe there is still some volume drop (although I added the mods like in Bernard's unit) compared to true bypass but I can't say for sure since I did not connect the circuit to a stompswitch.

Regards,

Markus
« Last Edit: May 27, 2006, 03:31:14 AM by markusw »

markusw

Re: 9V Electric Mistress layout (Bernardduur??)
« Reply #17 on: May 07, 2006, 12:41:48 PM »
Here is the promised profect file

http://www.diystompboxes.com/DIYFiles/up/9V_Mistress_project_file_v1.pdf

and here's a pic of the guts



The pots will have to be replaced with others but I'm still waiting for the rev 1M pot.

Please report bugs.


Have fun,

Markus
« Last Edit: May 07, 2006, 02:29:10 PM by markusw »

markm

Re: 9V Electric Mistress project file done (Bernardduur??)
« Reply #18 on: May 07, 2006, 01:21:17 PM »
NICE.
Thank you very much :icon_biggrin:

redeffect

  • Guest
Re: 9V Electric Mistress project file done (Bernardduur??)
« Reply #19 on: May 07, 2006, 01:35:53 PM »
A HUGE thanks for all the hard work, R&D, layout, debugging,(the list goes on...) you did on this effect! You have done a truly great thing sharing your efforts with all of us. Guess it's time to finally build one :icon_cool:
Thanx again, and all the best,
red