DIYstompboxes.com

Anyone know what goes on in a 20 second looper? Is there anyway to mod a GGG PT-80 or similar to get storage like that? Maybe a schematic somewhere?

Its probably based on a voice recorder chip like those used in answering machines or stupied singing fish.

I don't think you can mod a PT-80 to do that.

Andrew

I believe the Lo-Fi Loop Junkie is built around a "chipcorder" device from ISD (which was bought by Winbond).

The technology uses what are normally digital EEPROM cells to store analog values. The chip fabrication process is more suited to digital info, thus the Lo-Fi aspect. :D

http://www.winbond-usa.com/

The best (read as most flexible) control of these chips is done via microcontroller, but I don't know if that's the route that Zachary took with his design.

A PT-80 cannot do such things because the PT-80 is based on a much smaller amount of RAM to save the audio.

Based on the specs for the Lo-Fi Loop Junky my guess is he's using the ISD1420 chip. The ISD1400 series of chips are actually very well-suited for easy pushbutton control compared to some of the more recent chips in the ISD family. You could build a pretty simple looping circuit using this chip, but it's the modulation features that give the ZVex pedal its little special something. I've got an ISD1420 lying around that I was hoping to experiment with when I find the time.

it's a winbond 1420 with proprietary control circuitry.

http://www.winbond-usa.com/products/isd_products/chipcorder/datasheets/1400/ISD1400.pdf

That's the datasheet.  It has an example circuit (simple!) for connecting a mic and speaker.

Quote from: zachary vexit's a winbond 1420 with proprietary control circuitry.

... and thats what I respect about ZV - answers a question and seeds another to help us along. Cheers guy  :lol:

TY ZVex! I appreciate your response (and all the others too).

BTW ZV - I spent quite a while watching videos on your site last night. You have built some great things!

I play with that family of ICs before. I built a more sophicsticated recorder that has four recording banks that can be called up on demand. It has loop as well. Minimal logic used. Very simple.

Andrew

P.S. I wasn't kidding about the singing fish either.

Yeah you're not kidding, those things are stupid

I've played with a 2532 and got mixed results.  I think that the 1400's are more user friendly for us DIYers.  I talked to someone who fooled around with the XCLK pin and the results sounded very interesting.  Once I dig myself out of this hole I will try to get around to trying them again.

-Colin

Yeah there are other familes of those ICs which are much better for DIY stuff. I might even do an article on it.

Quote from: SamuelYeah you're not kidding, those things are stupid

I hacked one of those. They use one of these ICs to store the audio with a power amp driving the speaker. It has motors to articulate the movements like the head, mouth, and tail. Everything is controled and sequenced by a PIC. By reprogramming the PIC and recorder IC you can make it do different "things". hehehe.

Andrew

Please do tell. Both on the IC's and the fish ;)

Quote from: Mike BurgundyPlease do tell. Both on the IC's and the fish ;)

While Mr. Vex just use the 20sec version there are other ICs that can hold a lot more time. On some of the familes you can directly access what part of the memory to start at. This is how things like answering machines store multiple messages. Its also how the fish works. They load up all the clips into the IC at the factory and have the PIC call up each clip's starting address. The only tough part is getting the PIC to control the motors in sequence with the audio.

For my recorder I used a 2min version which I broke up into four 30sec banks. I use the same trick of calling the starting address but I use very basic logic stuff. No mircoprocessors although using one could add a processor for some more features.

If theres enough interest I might write an article of how I did things.

Andrew

andrew, thats sounds really really interesting, im sure all of us would love to hit goodwill and buy a cheapfish for like 2 bucks... LOL

i can see the news now "SUDDEN CRAZE STRIKES GOODWILL:: SINGING FISH GOING LIKE HOTCAKES!!"

lol

Sometimes I get silly gifts so I get my revenage by hack them. Some of them have even been turned into guitar effects.

Oh it uses a Atmel processor not a PIC. I did this a long time ago with some help so I forget the details. Here are some sites for kicks:

http://entertainment.howstuffworks.com/singing-fish.htm

http://www.mit.edu/~vona/bass/bass-details-billy.html

http://www.mit.edu/~vona/bass/bass.html

Andrew

Question about the 1400 - on the "sample schematic" they show the chip driving a 16 ohm speaker. Does this chip really put out that kind of power? with 5V? ?? Or does this mean it can go from there to a standard audio amplifier? like a cd player or tape deck...

The same schematic shows a microphone in - what would be done differently to use a guitar as the input? "Not much" would be the answer I'd guess at. Both would deliver a similar (unamplified) power level.

per this page: http://www.winbond-usa.com/products/isd_products/chipcorder/datasheets/1400/ISD1400.pdf

I built a pedal with the ISD2560. Here is my web page:

http://humano.ya.com/guruzeta/Guitarra/dirtysam/

It is in spanish (sorry about that), but schematics are in english:
Digital design:
http://humano.ya.com/guruzeta/Guitarra/dirtysam/digital.html
Analog Design:
http://humano.ya.com/guruzeta/Guitarra/dirtysam/analog.html
Power Supply:
http://humano.ya.com/guruzeta/Guitarra/dirtysam/power.html

The schem. is missing a pull down resistor in the inFX.

I planned to translate it, but I am very busy lately

These look cool but... what about the finite life span of the EEPROM storage in these chips?  100,000 write cycles sounds like a lot but that works out to about 23 days of continuous 20-second loops.  Plenty for an answering machine but well under the expected life span of a pedal.  Maybe the write cycle specification is very conservative?  How do they behave as they die, is it a sudden event or does the sound quality degrade gradually as storage cells go bad?

Awesome! Thanks for posting your schematic gurutzeta. Any sample clips?

Can you translate the "Descripcion del efecto: " section? I get that it has an effects loop... the four jacks:

in
out
efx in
efx out

the fourth? what is "in MBP"?

Once you have recorded and start the 'play' cycle  - does it loop once or continuously? Looking at the datasheet for the chip it seems like it only plays once for each switch click.

Quote from: BennyThese look cool but... what about the finite life span of the EEPROM storage in these chips?  100,000 write cycles sounds like a lot but that works out to about 23 days of continuous 20-second loops.  Plenty for an answering machine but well under the expected life span of a pedal.  Maybe the write cycle specification is very conservative?  How do they behave as they die, is it a sudden event or does the sound quality degrade gradually as storage cells go bad?

Whoa there - don't think of it in terms of continuous loops, since the thing can't do sound on sound recording.  You start recording, it stops after 20 seconds or when you tell it to, whichever comes first, then it plays back.  100,000 write cycles is a LOT.  If you record 100 loops per day, every day, it will last you a bit under 3 years.

The other thing is, you'll probably have to replace the switches you use 3-10 times (or more!) before you replace the chip!  Which is a bigger PITA, replacing a switch or popping in a new chip - I vote the former.

Quote from: ethrbunnyAwesome! Thanks for posting your schematic gurutzeta. Any sample clips?

Not yet, I have been very lazy with this whole project.

Quote from: ethrbunny
Can you translate the "Descripcion del efecto: " section? I get that it has an effects loop... the four jacks:

in
out
efx in
efx out

-Two stompswitches, one for fx-bypass the other to change between play/record.

- Three potentiometers: Recording volume, play volume and tone control.

- Fx loop (in case you want to add and effect to the recorded sound)

- A switch to avoid overwriting the stored audio.

- It can record up to 120 seconds with bad quality or up to 60 with not so bad quality (depends on the chip used)... Still, it is Lo-Fi, it has noise, hum and hiss.

- Purely analog storage, no ADC or DACs.

- Chip available in amidata (the equivalent of the british RS components)

- The name dirtySam comes from the film Casablanca: "Play it again Sam... BUT WITH NOISE!!!"

Quote from: ethrbunny
the fourth? what is "in MBP"?

Millennium bypass... see GEOs web for more details

Quote from: ethrbunny
Once you have recorded and start the 'play' cycle  - does it loop once or continuously? Looking at the datasheet for the chip it seems like it only plays once for each switch click.

Loops continuously, the chip has different modes of operation, maybe you are looking at the wrong mode in the datasheet.

Does the bypass jack give you a 'clean' signal regardless of whether the loop is playing or not?

Ill go back to the datasheet and try to understand the modes. Thanks for the translation!

Quote from: ethrbunnyDoes the bypass jack give you a 'clean' signal regardless of whether the loop is playing or not?

The signal is completely clean when the pedal is bypassed (by pressing the bypass switch) and it goes trough an opamp based mixer with a gain of 1 when it is not in bypass mode (when recording or playing). Is that clear? what do you mean with "bypass jack"?

Quote from: ethrbunny
Ill go back to the datasheet and try to understand the modes. Thanks for the translation!

I do not remember the mode I am using, I will need to get back to my notes (which are in some box somewhere). I moved of house and country right after I designed the pedal, reason why I kind of left this project aside slightly (and all other guitar DIY), but I am starting to get settled, so I might do some improvements on this web page soon (translating it to english is on the list)

I guess Im still hazy on what the 'MBP' jack is for on the schematic.  Im still confused about what the fifth jack is for.

After going through the data sheet for the chip I *think* that I have some understanding of the mode(s) and how you are running it. Now Im working my way through your digital logic....

Quote from: ethrbunnyI guess Im still hazy on what the 'MBP' jack is for on the schematic.  Im still confused about what the fifth jack is for.

OK, I get it now. MBP is not actually a jack, it is just a connection point that goes from one page to another of the schem (from the analog circuit to the digital one). The fifth jack you can see in my box is actually a power connector, it is not a jack. The box I used came from a 4 input microphone mixer and, when I took the picture, I had not bother to put any labels to the connectors or potentiometer or to remove the existing ones (INPUT, OUTPUT and so on...). I did reuse the hole of the output jack of the mixer to put my power connector.

Hope that is clear now

Much clearer. Thank you v much.

lo fi loop junkye's best sounding effect since... univibe!
Hearing the samples it turns any stringpluck into shimmering pop tunes!

Z-vex this your masterpiece!

(And what about the unconstent tremolo that pulses in its heart?)

hmm i know i shared this with sic.  but to do fun things in that same vein.

there is a cheap kit available from circuitspecialists.com  in their kit section and all you need is to wire up a couple of foot switches and something to freak out the clock.

i ocudlnt' find the online link but its in the catalog and in stock i am not at home or i woudl go look it up.. however its quite nice and sound really good. by lifting the ground you disable the internal clock function.   and you can get 40seconds continuous play with the kit which is around 28usd

Gurutzeta - I can't get the link to the PC board to open. Its a .doc file but MS Word won't open it.

I'd like your permission to create and populate one of these boards. It wouldn't be for sale - just for me. Let me know if this is a problem.

Quote from: ethrbunnyGurutzeta - I can't get the link to the PC board to open. Its a .doc file but MS Word won't open it.

Don't know what could be happening. I suggest you download the image from:

http://humano.ya.com/guruzeta/Guitarra/dirtysam/images/pcbdirtysam.JPG

and then resize it to 32% (I think)

Quote from: ethrbunnyI'd like your permission to create and populate one of these boards. It wouldn't be for sale - just for me. Let me know if this is a problem.

Sure, no problem, I will be honoured. Could you tell us how did it work out when you are done?

One thing that might be interesting would be to play a bit with the oscillator circuitry... I am sure we could create some sort of vibrato effect as the lofi junky has.

How would you go about adding the vibrato to the circuit? Just having the effects loop is v nice. Maybe just a 'blend' control to set how much the effects loop touches the sound.

Some questions about the schematic:

1) SW12 and SW20 appear to be connected by a trace - accurate?
2) FXin and FXout - only one connection point for each - is the other a ground?
3) Same for LED2 - only one connection?
4) You have 4 pots - but Im only seeing 1 pad for P2 and 2 for P3 - where are the rest?
5) what are FXlo and FXli for?

Thanks - the answers are probably right under my nose.

Quote from: ethrbunnyHow would you go about adding the vibrato to the circuit? Just having the effects loop is v nice. Maybe just a 'blend' control to set how much the effects loop touches the sound.

I would need to check the datasheets again, but I guess it is a matter of disconnecting pin 26 of the ISD chip (XCLK) from ground and putting there some weird oscillator that changes frequency... sort of a pwm of a sinusoidal LFO, maybe... I am not sure if I left that very clear.... basically you need to have a clock with an oscillating frequency... Something like the oscillator used for flangers, a VCO which is fed an LFO, I guess.... Anyway... lets go to what I can actually answer more precisely:

Quote from: ethrbunny
Some questions about the schematic:

1) SW12 and SW20 appear to be connected by a trace - accurate?
2) FXin and FXout - only one connection point for each - is the other a ground?
3) Same for LED2 - only one connection?
4) You have 4 pots - but Im only seeing 1 pad for P2 and 2 for P3 - where are the rest?
5) what are FXlo and FXli for?

Thanks - the answers are probably right under my nose.

1) That is correct
2) Correct again
3) Wrong!!! That one goes to 9V (you can see it in the schem)
4) There are only 3 pots:
* P1 (the play volume control) is after R7 and R6 and before LM386. It is used as a variable resistor, so you only neer to connect the middle pad and one of the other two. Depending on how you connect it it will work clockwise or anticlockwise.
* P2 (Record volume control)  is connected between R8 and C6 (and 2 pins of the TL074). It is again working as a variable resistor.
* P3 (tone control) works as a variable resistor also, so again you only need to of its pads (which you have found)
5) FXlo is FX loop out. That is the send of the FX loop
   FXli is FX loop in. That is the return of the FX loop

FXin comes from the jack and InFX comes from the switch? Its making more sense now. Pardon my ignorance.

On the digital design page - what is the symbol immediately to the right of the inMBP jack? a JFET?

Quote from: ethrbunnyFXin comes from the jack and InFX comes from the switch? Its making more sense now. Pardon my ignorance.

inFX comes from the switch. Where did I use FXin, I do not seem to find it.

Quote from: ethrbunnyOn the digital design page - what is the symbol immediately to the right of the inMBP jack? a JFET?

It is a JFET. I use BS170. Please check geofex for more info about the millenium bypass circuit: http://www.geofex.com/Article_Folders/Millenium/millen.htm

Looky here!
http://www.twinhunter.com/catalog_detail.php?id=243

RDV

RE: caps in the layout -

I got the PC board in the mail today and most of the parts from Mouser. Still haven't tracked down a good place to get the ISD2560 from.

In the spec - you don't give an indication of the polarity of the caps. Is there a cue for this that Im missing?

Quote from: ethrbunnyIn the spec - you don't give an indication of the polarity of the caps. Is there a cue for this that Im missing?

I assumed those capacitors  bellow 1uF are non polariced (i.e. ceramic, polyester...). For those above or equal to 1uF, you will need to check the schem. The curved side is the negative and the straight is the positive (I hope nobody gets offended by this :wink: ).


Positive +            Negative -

          o---|(---o



If you have any doubts about any specific capacitor, let me know.

32% scaling of the jpg was too small. Is there anyway to figure out what the proper scaling would be before I order a new board?

Quote from: ethrbunny32% scaling of the jpg was too small. Is there anyway to figure out what the proper scaling would be before I order a new board?

Print it and check that the distance between holes of pins of the opamps is correct, for example. That is how I did it at least.

crp

Quote from: Torchy

Quote from: gurutzetaIt is a JFET. I use BS170.

Thats a mosfet ...

Thanks for the correction, I was testing to see if you all were paying attentiont  :wink: .

Im trying to decide whether or not to 'frankenstein' the board with jumpers to a board with just the ICs. .. hmm.. what is my time worth.. hmmm...

ok. got a new board. sockets fit now. am slogging ahead!

this is gonna be righteous

Quote from: Michael Allenthis is gonna be righteous

.. lets hope ..

Im still questing about for enclosures for this and for a 'fender blender'.  Suggestions?

Hmm... I wonder if my daughter would miss her elmo doll..

"daddy - why are you stepping on elmo? and why are his eyes blinking?"

Gurutzeta - 2 questions

1) what is d4? another 1N4148?
2) R8 - 3.2M ? Really?

Hopefully I can post a pic of the built board soon.

how bout a picture of the board itself?

Quote from: gurutzeta

Quote from: ethrbunnyHow would you go about adding the vibrato to the circuit? Just having the effects loop is v nice. Maybe just a 'blend' control to set how much the effects loop touches the sound.

I would need to check the datasheets again, but I guess it is a matter of disconnecting pin 26 of the ISD chip (XCLK) from ground and putting there some weird oscillator that changes frequency... sort of a pwm of a sinusoidal LFO, maybe... I am not sure if I left that very clear.... basically you need to have a clock with an oscillating frequency... Something like the oscillator used for flangers, a VCO which is fed an LFO, I guess....

it's easier to just vary the supply voltage to the chip.  8^)  but don't go too high!  it'll make the chip freeze up.  the trick is to set up an oscillator that varies the chip's power supply in equal amounts up and down from the record voltage (and turn off the vibrato during record, of course) so that the average pitch is about equal to the original guitar pitch and the overall time for playback is identical to the time it takes with the vibrato off... if your oscillation biases the average dc voltage lower than the non-vibrato voltage, the loop will play longer with the vibrato on, the sample will play back generally flat, and it will screw up the timing during performance.

Quote from: RDVLooky here!
http://www.twinhunter.com/catalog_detail.php?id=243

RDV

hmmmmmm......ready made looper.....

Quote from: ethrbunnyGurutzeta - 2 questions

1) what is d4? another 1N4148?
2) R8 - 3.2M ? Really?

Hopefully I can post a pic of the built board soon.

1) Yes, all diodes are 1N4148.
2) Yes, I used 3.2 M. It is making an inverter amplifier together with OA2 and P2. The relationship is ANAin = - ( P2/R8 ) * InFx
You might replace it with a different value if you also change P2 (as long as you keep the same value for P2/R8 )

Quote from: zachary vex
it's easier to just vary the supply voltage to the chip.  8^)  but don't go too high!  it'll make the chip freeze up.  the trick is to set up an oscillator that varies the chip's power supply in equal amounts up and down from the record voltage (and turn off the vibrato during record, of course) so that the average pitch is about equal to the original guitar pitch and the overall time for playback is identical to the time it takes with the vibrato off... if your oscillation biases the average dc voltage lower than the non-vibrato voltage, the loop will play longer with the vibrato on, the sample will play back generally flat, and it will screw up the timing during performance.

Shit!!! did not think about that!!! Thanks ZVEX...

hi! guys
so thanks gurutzeta!

it's HUGE

I want to mad this effetc but can I put ISD25120P  with 120s into that circuit???. so i can I have 120s , maybe it's not useful to have a lot seconde loop??

Where I can thes IC??
http://www.jameco.com??? is good??thanks

Quote from: mathflanI want to mad this effetc but can I put ISD25120P  with 120s into that circuit???. so i can I have 120s , maybe it's not useful to have a lot seconde loop??

You could do it, but it would reduce the quality of the looped sound dramatically. Up to you.

Quote from: mathflanWhere I can thes IC??
http://www.jameco.com??? is good??thanks

I got them from http://rswww.com

Why would the longer-storing winbond chips have a lower quality of playback?

you can look at the frequency response of each type of winbond chip at their website.  they vary from somewhere in the 2k range to above 3k... i have listened to the 3k versions and i've found that not only do they sound somewhat more noisy because of the filter response, but they have a very annoying tone to them with that hard knee near 3k.  it's actually a smoother sound to have them rolled off in the mid 2k region because it's easier on the ear.  people over 30 especially have a sensitivity to sounds in the 3k "spike" area of the spectrum.  sometimes, more is NOT better.  8^)

i don't think that the longer winbond chips have a response that's much lower than the short ones.  the biggest problem with winbond is that they changed their control circuitry so many times that it makes your head spin when you try to come up with circuits to make them into effective loopers.  the one i use, the 1420, can be replaced with another in the 1400 series that is slightly shorter but has higher frequency response, and i've never liked a thing about it.

Eeeek.  :shock: Well, I ordered a 2560 for my Gurutzeta box.. I hope it will work ok.

Quote from: ethrbunnyEeeek.  :shock: Well, I ordered a 2560 for my Gurutzeta box.. I hope it will work ok.

60 should be OK is from there onwards that starts getting bad. Basically the 120 is the same chip as the 60 but with a sample frequency of half of the one in the 60.

Bellow 60 the chips are the same as the 60 (sample frequency wise) but with less capacity, less "analog memory"

Quote from: zachary vexthe biggest problem with winbond is that they changed their control circuitry so many times that it makes your head spin when you try to come up with circuits to make them into effective loopers.  the one i use, the 1420, can be replaced with another in the 1400 series that is slightly shorter but has higher frequency response, and i've never liked a thing about it.

I seem to remember reading in the datasheet that the new chips (ISD25...) control circuitry is somehow compatible with the old chips (ISD14...).

Quote from: gurutzeta

Quote from: ethrbunnyEeeek.  :shock: Well, I ordered a 2560 for my Gurutzeta box.. I hope it will work ok.

60 should be OK is from there onwards that starts getting bad. Basically the 120 is the same chip as the 60 but with a sample frequency of half of the one in the 60.

Bellow 60 the chips are the same as the 60 (sample frequency wise) but with less capacity, less "analog memory"

man, that sucks!  i never researched those really big chips, because it was impossible for me to make everything fit in a small form factor.

On reply to some questions sent to me on private messages:

Sw10 in the pcb (over c16) should go to the pole of one of the circuits of the DPDT switch used for the safe switch

SW12 is connected to SW20 and should go to one of the throws of SW10


Safe DPDT Switch

open---o o---5 Volts
sw10---o o----(470 ohm resistor)---( LED )---Ground
sw12---o o---Ground




sw20 is connected to the pole of the Play/Rec Stompswitch



PLAY/REC Stompswitch

N.C.---o o---5 Volts
N.C.---o o---SW20
N.C.---o o---Ground



sw22b and sw20b  should be connected together in the PCB. I used to have them connected to the Play/record stompswitch but it made a horrible pop at the end of a loop, so just connect them together.

About the two color LED, it should be one with only two connections coming out of it, not the one with three connections. There are 2 types of bicolour LEDs, with 2 or with 3 leads. You need the one with 2 leads: 228-5641 in RS components in the UK.

Remember to put a 1Meg resistor between inFX and Ground, I forgot to put it in the PCB.

Last... T1 is a mosfet so there are no E, B or C pins on it, instead it has S, G, D. D is connected to LED2, G in the middle and the other one is S

Grand. Back to the garage.

This build has me psyched out somehow. I can't seem to get a handle on finishing it. Silly.  :roll:

oooookay.. so I finished this build today. (freezing rain is falling outside - my kids are going nuts.. so naturally i retreated to the garage. It may be only 20 degrees in there but its *quiet*)

The circuit *works* with a few minor issues:

1) led2 won't light up. Im using a BS170 for the FET.
2) turning the pot for playback volume gives me a radio station on one end and doesn't really bring the playback volume to anything near a usable level
3) Theres a background hum that overpowers the playback (in addition to #2 above)

On the 'analog' page you have the FX loop with a 'jack switch'. Can you tell me what this is? I put a DPDT switch on mine but I notice from your pictures that you only have 2 stomp switches and 1 toggle.

Ill start poking at electrolytics and looking for solder bridges.

So i tried throwing together the Dean Hazelwanter Version (there wasn't a full schematic, just the op-amp layout) and so far i have recording, and looping... but it is REALLY splatty... it sounds like the guitar is  WAAAAAAAY overdriven almost to a point where you can not understand what is going on. Also i seem to have a large volume drop playing straight through it... when in bypass its loud, then when i play through the op-amps and the chips... i get WAAAY less volume.

I'm using the ids1420 and 2 TL072's.

also i didn't include the record volume, just left it with a .01uf cap straight into the ana in


the op-amp schematic im using is Loopy (http://generalguitargadgets.com/pdf/ggg_loopyAnalog.pdf)

comparing what i have to the PCB layout, i don't have the 4001 ic...


i have a good start i think, but a long ways to go... hehe... i wish the GGG version had a little more documentation along with it, but beggars can't be choosers.

Thanks ahead of time

man, i've been staring at this all day, and i don't have a clue what needs to happen to get this working like i want it to

Both schematcs (digital and analog sections) are here: http://generalguitargadgets.com/index.php?option=content&task=view&id=203&Itemid=228, as well as the board layouts. For some reason (likely time constraints) JD didn't include the (brief) build notes I sent, so here they are:

Release Notes:

General
- Inspired by VZex's LoFi Loop Junkie and
- Based on 20 second voice recorder chip, Winbond ISD1000A - Why, because I had one. Although they are obsolete, some RadioShack stores still have them (276-1325) in their discount bins.
- Three pots: Record Level (to optimize the signal level going into the ISD1000A), as well as Playback Level and Dry Level.
- Two footswitches : Record/Play (lights red 'Record' LED in record position), and On/Off (lights green 'On' LED in on position). 'Record/Safe' switch (toggle or slide) helps to prevent over-writing saved loop

PCB
- There is a long vertical jumper near the middle of the board, which carries the signal into the ISD1000A. Notice that there is an extra, grounded, pad to the right of the bottom of this jumper. When I laid out the PCB, I put this ground pad in case the long jumper picked up noise, so the jumper could be shielded. It doesn’t seem to be a problem, so the jumper doesn’t need to be shielded.
- All of the off-board wiring is laid out to use 3 pin 0.1" center connecters that I've been using for a while. One connector for the 2 switches, one for the 2 LEDs, one for each of the 3 pots, one for each of input and output jacks, and one for 9v DC.
- The corners of the PCB can be notched out to mount it in a 1590B, or just drill the corner pads for using standoffs.
- I mounted the disc cap across the looper chip power supply pins directly to the back of the PCB. One end of a 0.1uF cap goes to pin 12&13, the other end goes to pin 28.
- For the 5 volt voltage regulator, you can use either the 7805 (TO-220 case) or the 78L05 (TO-92 case). The PCB is laid out with the 7805 outline, with the front (the side with the writing) pointing to the right of the PCB. If the 78L05 is used, face the front of it (the side with the writing) to the left of the PCB.

Hope this helps!

soon come: EOL for some of Winbond`s most popular chips...
:icon_eek:


:icon_wink: :icon_wink:

Quote from: puretube on September 14, 2006, 04:47:39 PM
soon come: EOL for some of Winbond`s most popular chips...
:icon_eek:

Which is one of the reasons I created Payback. ;)

Andrew

Quote from: puretube on September 14, 2006, 04:47:39 PM
soon come: EOL for some of Winbond`s most popular chips...
:icon_eek:

that`s why I re-bumped this very thread,
so that all subscribed contributers get to read it...

:icon_wink: :icon_wink: :icon_wink:

Quote from: puretube on September 14, 2006, 05:43:36 PM
that`s why I re-bumped this very thread,
so that all subscribed contributers get to read it...

Link/source ? I don't see anything on their site.

Andrew

large websites are slower than internal emails from large industry-suppliers...
(received today...)

Quote from: puretube on September 14, 2006, 05:49:36 PM
large websites are slower than internal emails from large industry-suppliers...
(received today...)

Do you know what lines are going ? (i.e. ISD14xx, ISD25xx, etc.)

Andrew