Here's a Redraw of the Factory Schematic of the EHX - Full Double Tracking Effect for those of you with poorer eyesight, I think the Redraw is True to its source, I can't recall where I got the original Factory one from and nor can I confirm its Authenticity so if someone knows the link to that or if it's correct, that'd be handy.
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/EHXFullDoubleTracking.gif?t=1286719834)
I might see about converting it to 9V & V3205s as it's quite a nice simple looking Delay Project.
The EH Mans Article on the Pedal and its Predecessors - http://electroharmonix.vintageusaguitars.com/index.php?option=com_content&view=article&id=31:ehs-other-delays-part-1-batteries-not-included&catid=13:electro-harmonix-articles&Itemid=45
Converting this to V3205... could I forego the Power Supply section and just give the whole thing 9V straight from a battery, swap the pin connections on the V3205 as usual and then just use a 5V Zener to give it its bias voltage? (As it's only rated up to 8V and runs best at around 5V).
Or is that a little bit too simple...?
Crap, Realised I missed a Ground Connection off the MN3005 -
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/EHXFullDoubleTracking-1.gif?t=1286893112)
(How do you go about replacing images on photobucket without having to change the link and repost them? Any way?)
Found where I got the original too - http://sites.google.com/site/electroconducive/EHXFullDoubleTrackingEffect.pdf (Cheers Nelson if you're still around)
Can someone explain why Vdd & Gnd are linked on the 3005... is that right?
I've been interested in building one of these pedals for a while now. Seems like it would be a pretty "first delay" project. Hope you work it out.
Quote from: dmc777 on October 12, 2010, 10:53:30 AM
I've been interested in building one of these pedals for a while now. Seems like it would be a pretty "first delay" project. Hope you work it out.
I think i've basically worked out the best way to do the conversion now (With a helping hand) It just needs Breadboarding to Verify it, i'll post the schematic here afterwards (might be a bit off though as no chance to get to the breadboard)
Right... this has now been verified with a 3205 chip and it works well, ableit needing a few refinements to bring the pedal into the modern age.
What I was thinking though, was if there'd be interest in a fabbed, double sided, silk screened PCB to fit a 1590B enclosure with battery using the 8 - Pin DIP Version of the 3208 Chip available at smallbear (assuming that works upon testing rather than the 3205, don't see why it wont as the full delay of the 3205 isn't utilised) laid out like the EHX Nano Stone/Clone (Pot to the right, switch to the left side) with onboard pot.
I think it'd make a good sorta, babies first BBD Delay project, from the clips i've heard (I couldn't breadboard this myself as I don't have access to my electronics so this was performed for me) it sounded very nice as a slap back delay and I think for a 1590B project, it'd be pretty nice to have and also give a very simple insight into how BBD based effects work for people interested in learning (Doesn't get simpler than the Clock, BBD & Single OpAmp set up) at speculation say the boards were... $7 each? What would everyone think of that? So I know if it's worth looking in to.
I'd buy a board. Woundn't hesitate. :-)
Okay... here's my first ever attempt at a PCB layout for a pedal so go easy on it... it's not the greatest and I haven't checked it but it's a proof of concept atleast to get this into a 1590B with a Board Mounted Pot (Pot Mounted on Back) and hopefully battery too.
Here's the verified schematic for the 3205 version I dropped the 0.1uF Cap and 1N4001 from the power supply section as there just wasn't room.
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/EHXFullDoubleTracking3205.gif?t=1290545479)
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/FDBSS.gif?t=1290546278)
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/FDBPCB.gif?t=1290545479)
Board measures 53.34 x 53.34
Do any of the PCB gurus have any tips from what i've done? If I used stand up resistors or upped the enclsoure to a 125B I could probably get it in but i'd much prefer not to, I know it's kinda ugly in places but I quickly lost room, hence the generally squished areas and one large jumper aswell as 6 smaller ones.
Any feedback however harsh will be appreciated :)
Corrected missing ground trace -
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/FullDoubleTrackerPCB-1.gif?t=1290804175)
No love for this effect? :'(
No love for BBDs scruff!
Quote from: Hides-His-Eyes on November 26, 2010, 06:00:56 PM
No love for BBDs scruff!
Damn you PT2399 *Shakes Fist at Sky*
heh heh maybe i'm tired or maybe it's what i just inhaled but that was funnay and i wanna say so
Quote from: Scruffie on November 26, 2010, 03:47:13 PM
No love for this effect? :'(
Did you build this thing? If so, and samples?
I like the double track sound and it looks like you can do the same thing with a regular delay, but my PT-80 just sounds like a reverb when I try.
Quote from: chi_boy on December 28, 2010, 07:05:39 PM
Quote from: Scruffie on November 26, 2010, 03:47:13 PM
No love for this effect? :'(
Did you build this thing? If so, and samples?
I like the double track sound and it looks like you can do the same thing with a regular delay, but my PT-80 just sounds like a reverb when I try.
I haven't yet as i'm still waiting on a PCB I ordered from someone a month or so ago however I have heard samples (I was asked not to post them) and it sounded pretty damn good to me.
Could they be PMed? I've never heard of this effect, but it seems interesting enough, if I could hear what it sounds like.
Quote from: azrael on December 28, 2010, 07:21:20 PM
Could they be PMed? I've never heard of this effect, but it seems interesting enough, if I could hear what it sounds like.
Urmm, i'll ask him.
It sounds like a short slap back delay or a reverby delay though depending where you set the switch, it was nice even on a camera phone recording.
Is he shy about his playing? No need to be, if it is. It's about the effect, not a talent show.
Quote from: chi_boy on December 28, 2010, 09:24:07 PM
Is he shy about his playing? No need to be, if it is. It's about the effect, not a talent show.
No idea, he just asked me not to post them when he gave them to me, probably due to the poor audio being a camera phone recording and all.
Quote from: Scruffie on November 23, 2010, 03:55:27 PM
Okay... here's my first ever attempt at a PCB layout for a pedal so go easy on it... it's not the greatest and I haven't checked it but it's a proof of concept atleast to get this into a 1590B with a Board Mounted Pot (Pot Mounted on Back) and hopefully battery too.
Here's the verified schematic for the 3205 version I dropped the 0.1uF Cap and 1N4001 from the power supply section as there just wasn't room.
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/EHXFullDoubleTracking3205.gif?t=1290545479)
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/FDBSS.gif?t=1290546278)
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/FDBPCB.gif?t=1290545479)
Board measures 53.34 x 53.34
Do any of the PCB gurus have any tips from what i've done? If I used stand up resistors or upped the enclsoure to a 125B I could probably get it in but i'd much prefer not to, I know it's kinda ugly in places but I quickly lost room, hence the generally squished areas and one large jumper as well as 6 smaller ones.
Any feedback however harsh will be appreciated :)
This is an old thread, but I figured I would give it a try... I've etched and built Scruffie's PCB layout and I've got it all finished except for R19. I can't see to find it on the schematic. Am I blind? It's driving me crazy! If anyone can help I would be grateful.
It is a bit confusing. Connects between 9V and pin 5 of the BBD. According to the schematic, pine 5 and R7 go to ground, but I'm not seeing this on the layout?
Sorry aishabag23, I did see your PM on the other site but I was on holiday at the time.
It's just a filter resistor, 22-100R should be fine.
No idea if this layout works, as I said at the time, it was my first ever PCB layout and it certainly shows.
Quote from: mth5044 on December 07, 2016, 10:19:22 PM
It is a bit confusing. Connects between 9V and pin 5 of the BBD. According to the schematic, pine 5 and R7 go to ground, but I'm not seeing this on the layout?
If you look at the symbol it's actually the 9V symbol, not ground :)
Yeah, that's where I got confused, too.
Quote from: Scruffie on December 08, 2016, 06:43:03 AM
Sorry aishabag23, I did see your PM on the other site but I was on holiday at the time.
It's just a filter resistor, 22-100R should be fine.
No idea if this layout works, as I said at the time, it was my first ever PCB layout and it certainly shows.
Quote from: mth5044 on December 07, 2016, 10:19:22 PM
It is a bit confusing. Connects between 9V and pin 5 of the BBD. According to the schematic, pine 5 and R7 go to ground, but I'm not seeing this on the layout?
If you look at the symbol it's actually the 9V symbol, not ground :)
Hey Scruffie, thanks for your reply. Your layout works perfectly, it sounds exactly like the vero version I built. I would love to make a clone of the original MN3005 version on an etched PCB. I think this thing would sound fantastic as an always-on thing for me if it could run cleaner, at 15v. You wouldn't happen to have done a PCB of the MN3005 version, have you? Thanks again for that resistor info!
I'm afraid I didn't do one for the MN3005 version no, sorry man!
Quote from: aishabag23 on January 23, 2017, 11:42:07 AM
Quote from: Scruffie on December 08, 2016, 06:43:03 AM
Sorry aishabag23, I did see your PM on the other site but I was on holiday at the time.
It's just a filter resistor, 22-100R should be fine.
No idea if this layout works, as I said at the time, it was my first ever PCB layout and it certainly shows.
Quote from: mth5044 on December 07, 2016, 10:19:22 PM
It is a bit confusing. Connects between 9V and pin 5 of the BBD. According to the schematic, pine 5 and R7 go to ground, but I'm not seeing this on the layout?
If you look at the symbol it's actually the 9V symbol, not ground :)
Hey Scruffie, thanks for your reply. Your layout works perfectly, it sounds exactly like the vero version I built. I would love to make a clone of the original MN3005 version on an etched PCB. I think this thing would sound fantastic as an always-on thing for me if it could run cleaner, at 15v. You wouldn't happen to have done a PCB of the MN3005 version, have you? Thanks again for that resistor info!
hahaha, yeah, the original one wants to see 18v. don't worry aisha, i haven't forgotten you, life's just been.... life.
i will get it boxed up hopefully this week. i wanted to pull it out and make sure it was working etc.
you know the drill... hound me!! ;)
i saw this thread and was like... wow, wonder if scruff needs an original to work from ;) nope ;)
Quote from: pinkjimiphoton on February 06, 2017, 11:44:22 AM
Quote from: aishabag23 on January 23, 2017, 11:42:07 AM
Quote from: Scruffie on December 08, 2016, 06:43:03 AM
Sorry aishabag23, I did see your PM on the other site but I was on holiday at the time.
It's just a filter resistor, 22-100R should be fine.
No idea if this layout works, as I said at the time, it was my first ever PCB layout and it certainly shows.
Quote from: mth5044 on December 07, 2016, 10:19:22 PM
It is a bit confusing. Connects between 9V and pin 5 of the BBD. According to the schematic, pine 5 and R7 go to ground, but I'm not seeing this on the layout?
If you look at the symbol it's actually the 9V symbol, not ground :)
Hey Scruffie, thanks for your reply. Your layout works perfectly, it sounds exactly like the vero version I built. I would love to make a clone of the original MN3005 version on an etched PCB. I think this thing would sound fantastic as an always-on thing for me if it could run cleaner, at 15v. You wouldn't happen to have done a PCB of the MN3005 version, have you? Thanks again for that resistor info!
hahaha, yeah, the original one wants to see 18v. don't worry aisha, i haven't forgotten you, life's just been.... life.
i will get it boxed up hopefully this week. i wanted to pull it out and make sure it was working etc.
you know the drill... hound me!! ;)
i saw this thread and was like... wow, wonder if scruff needs an original to work from ;) nope ;)
Jimi, you're the best!
Btw, I built your Os Mutantes Fuzz vero layout for a friend and it rocked so hard, I had to make one for myself!
I did up an MN3005 version but it's not a verified build so...
http://www.madbeanpedals.com/EP/index.html
Under the Delay section.
aisha, its yours once i can afford to ship it financially and time wise. i may still have a spare reticon chip for it too, if i can find it i'll stick it in with the FDTE
guys, this is a fairly crappy effect, why waste good chips on it?
seriously. tonally a 2399 sounds almost exactly the same, and would be a lot cheaper and easier to work with.
i know, i know, no mojo there...
but damn little in the original. ;) seriously. i got one. want a vid of it before i ship it off to aisha?
I know this is an old topic, but here goes anyways.
Are there any mods one can do to this circuit?
I know the Full Double Tracking Effect and the SlapBack Echo shares the name of a mode on the EchoFlanger/PolyChorus, and on those the Width, Tune and Feedback pots work in said modes, any chance you could add those pots to this effect?
The EchoFlanger schematic can be found here
https://experimentalistsanonymous.com/diy/index.php?dir=Schematics/Flangers
Since there wasn't much interest, I took it upon myself to look at other old ehx schematics to see if I could find some mods to do to this pedal.
First was easy, getting rid of the Blend pot, the way it well, blends between delayed effect and clean I didn't like, if you true bypass this it no longer reaches unity gain, and when you put a boost stage behind it, it just gets louder when turning the pot towards the clean signal. Remove the pot and the C2 22µF and the new effect out is the R13 & R14 section, add boost stage here if you want to true bypass it.
Second was the Delay switch, it doesn't do much with just 2 settings, so I got rid of the switch, R15/R16/R17 & C12 and then replaced D2 with a B100K pot wired in series with R18 between pin 2 and pin 3 of the 4047. This was taken from a Economy Memory Man found here: https://sites.google.com/a/davidmorrin.com/www/home/trouble/troubleeffects/electro-harmonix-memory-man/eh-1309a
Last was adding a feedback pot, what I found worked best was adding a B10K pot from the R13/R14 section and run it back to the Input (C1). This was taken from a different Economy Memory Man found here, but slightly wired differently as it didn't work like it was drawn. Adding a trimpot in series before the B10K pot will help controlling how much it will feedback.
https://sites.google.com/a/davidmorrin.com/www/home/trouble/troubleeffects/electro-harmonix-memory-man/eh-7810
Doing these mods did kinda what I was looking for, which was the Slab Back/Double Tracking mode on the EchoFlanger and PolyChorus pedals. Like I mentioned, on those pedals the Tune & Width pots still work and they kind of play off each other how the "delay" sounds, I wonder if I could add another pot that does the same thing to the FDTE.
Hi ,sorry to necro an oldish thread . Im a first time caller , a bit of a noob.
Just looking for a little clarification on the wiring of the delay switch from the original schematic re-draw at the start of this thread please.
I have an EHX Full Double doo dah to repair but the delay switch ( original ) is a SPDT , whereas on the schematic it shows a SPST . Is the solution simply to only connect 2 of the lugs of the original switch ? And . if so , would anyone be so kind as to tell me which 2? ( I presume , the centre lug and one of the outers ) . And to where?
From the schematic it looks like a single pole single throw with one side connected to the 47k and the other side connected to power . I'm thinking centre pole of SPDT to the 47k and one of the throws to power? Which , if correct , begs my next noob query. Is the power at the top of the switch 18v or the 12.5v reference or what ?
Thanks for your patience
hey man, welcome to the forum!
yeah, you can use an spdt. choose a side. center is common, only wire it up to one side of the two other poles, and you're good to go!
part two, ya already figured out.
keep us posted!
pink
Thanks for the welcome Jimi ,
Just to clarify .On my SPDT I should connect centre to the 47k and one of the outer lugs to 18v , leaving the remaining outer lug unused ?
Much appreciated man
I have quite a bit more to do to this pedal to get it back to life but for some reason this little thing with the switch/ schematic symbol discrepancy got me questioning my sanity more than usual .
P.S. sorry to bug ya about the power thing again , but that would be 18v on one end of the switch , rather than the 12.5v reference?
I look forward to reading this back in the future and being suitably embarrassed hehe
Cheers
i'd need to see the schematic, bro, been years
just looked. power to center pole, outer pole to 47k
Fantastic ! Many thanks again Jimi .
Maz
Never mind.