Echo Base - a new PT2399 delay

[mth5044]

That will work fine, the audio signal doesn't go anywhere near the switch. The bypass stomp controls a transistor switch which then switches the 4066 that turns the delay on and off. The switch is latching.

Ah ok thanks. So it's something similar to the 'wicked switch' on the Tone God's site? Maybe. Eh. Thanks for the info!

[slacker]

Yeah it's the same concept. I only need one inverter for my design so I used a transistor instead of a CMOS chip.

[hendrix2489]

I'd do it like this. Put the second pot in series with the original one, wired the same way. Then use a SPDT switch and connect the middle lug to where the pots join and the outer lugs to the outside of the pots, like this
           
Pin6----1---Pot-2--Pot--3--    Numbers are switch lugs

That way the will change between the 2 pot values without any break in the connection.

thanks, for the quick reply, cant wait to build it.

Alex S.

[sweetwilly]

re LFO switch discussed earlier in this thread. 

An SPDT (or half a DPDT) with Pin 1 of the LFO opamp in the centre, Pin 2 on one outside lug and nothing on the other would be the simplest way wouldn't it?  Is there any way an indicator LED could be added using a DPDT or 3PDT?  Could be more hassle than worth seeing as the modulation should be pretty obvious. 

I'm planning my build and am considering what extras to add.

Cheers.

[aloupos]

Took a bit of debugging with the condensed pcb layout, but this is a great sounding delay!  Sounds great by itself, but really shines when you dial in the more subtle tone shaping sounds that you would use in a real band context. 

Thanks Slacker!

[mth5044]

Son of a...

I got the wrong 7805 voltage regulator didnt I?

Here is a pretty awful picture



It looks like the middle leg is missing? And it doesnt have that loop on the top to attach the heat sink too.

On the top it says 7805BD2T RPU730 G

and this is the page I bought it from on Digi-key http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=MC7805BD2TR4GOSCT-ND

So.. is there a way to save this piece.. like just solder bridge up to that second missing leg or am I going to have to place a whole new order 

[slacker]

That's some sort of surface mount part, it will work though and the pinout is the same as for a normal one.
You could try soldering leads on to the tags or just do your solder bridge idea.

[slacker]

Actually if it's got a metal portion on the back you could solder a wire to that because that is connected to pin 2.

[hendrix2489]

just a quick question,  are the orientations of the diodes in this layout correct, because the band on the diodes are not in the square pads located on the pcb.
http://chawk.wordpress.com/files/2008/02/echo_base_pcb.pdf


thanks, Alex S

[slacker]

The way they a shown on the layout is correct. The band of the 1N4001 goes to 9 volts.
For the 1N4148s the band of one goes to ground and the band of the other goes to lug 2 of the feedback pot. It doesn't matter which one does what.

[boyersdad]

Hey!

Slacker, great job with this pedal! And a what a fantastic job with the support Great to see. I will be building one of these suckers over the weekend.

I just noticed though (good thing too 'cause I was just about to print my PnP) that the last layout you posted with the wiring diagram is different from the PDF file found here:  http://chawk.wordpress.com/files/2008/02/echo_base_pcb.pdf.

Is there a PDF (or at least a jpg or png) of the transfer for that layout? Looks a little tighter than the layout from the aforementioned PDF as well. Smaller the better!

Anyway, thanks again for this fantastic project. I'll be sure to post with my results!

Sean

[slacker]

Thanks for the comments.

Here's the newer layout by anonymousfacelesscoward http://blogs.yahoo.co.jp/anonymousfacelesscoward/23693577.html.

[Bucky Weaver]

I am new to this board, but have built 30-35 pedals and done my own layouts before so I am not a noob or an expert.
I built the Echo Base using anonymousfacelesscoward's layout^^^^^^.

My issue is having only wired stuff for true bypass, I don't think I have this thing wired right. The LED works but am ONLY getting a loud ground him whether in bypass or not bypass. No signal what so ever. Using a Godlyke 9v power supply.
My basic wiring is as follows:
The pots are correct because I check them multiple times after an early mistake. The LED is obviously right, it works.
The DC Jack Ground is going to Input shield. At the input shield I have the LED-, Ground from Board and Output Shield connected.
The DC Jack Positive is going to 9V+ on Board.
The Tips of the Jacks are wired to the indicated places on the board.

And assuming the DPDT footswitch lugs I am using are  labeled as:  1  4
                                                                                                  2  5
                                                                                                  3  6
The switch is wired as LUG 4 to the Bypass solder pad further from the CD4066 (to the BAse of the 2n5089, etc.) and LUG 5 to the solder pad closer to the CD4066 (Pins 5 & 7).
All component values are exact as the layouts/schematic except I used a 2n5087 for the BC560, which seemed to OK/workalike as previous indicate.

Is my wiring even the problem? I made sure there is no joined trace as it is a tight board.  All jumpers seem to be in place (no empty solder holes on board).

Any help would be greatly appreciated.

[Filament]

Bump for this guy....I'd like to know too. 

[slacker]

That sounds right for the wiring, theres a wiring diagram on page 14 of this thread if you want to double check. Your bypass switch wiring is correct and the fact that the LED works means that the 4066 part of the circuit is working.
First thing I'd do is check the orientation of the TL072s, they're upside down compared to the 4066 and PT2399, so pin 1 is bottom right. If you've put them in the wrong way round unfortunately you've probably killed them so they'll need replacing.

[Bucky Weaver]

Slacker, thanks. 
I had the TL072s orientated wrong. Replaced them and the 7805 which was defective and things are delaying now. Still have a little LFO/clock bleed and some settings are a little weird (whistle-type sounds?!), but I think these are problems people had and will check the thread for some help. You may see me posting again, when I get a chance to debug these minor issues some more.
I may wire it for true-bypass, because I don't mind the cutting off of the delay tails.
Sounds good though, outside of the issues.
Good job, slacker.

[Dimitree]

Would this pedal improve powering it with 12V or higher (without considering the 4066, I would remove it because I don't need tails) instead of 9V? If yes, what would improve?

[slacker]

In theory running it at a higher voltage would give the opamps more headroom. However, in practice I don't think it's very likely that you would overload the opamps at 9 volts, or if you did the signal would already be so dirty that any extra distortion from the opamps wouldn't make any difference.
More importantly the PT2399 only runs at 5 volts so it will distort long before the opamps do.

[Dimitree]

Thanks Slacker! I wanted to know if, besides the input and output opamps, there would be some improvements on the delayed signal..but the answer is no 
The PT2399 can only run at 5V? the datasheet I have doesn't tell that..
I'm asking that because I only need one strong (as the signal level) and clear repeat of about 220ms, as "digital" as possible.. just that..
I still haven't build this pedal so please tell me if it can do that..

[prnet]

Hello everybody!!

Finally I was admitted to the forum...
I read and studied all the 16 pages of the thread..
So 2 weeks ago I decided to build the echo bases because I like a lot the idea of tail circuit.

After lots of problems the fx now works well...
I post my build report, maybe some information
I would be happy if I could help someone that have problem to start echo on it's own fx.

19.11.2008 Italy
At the first the fx didn't work at all.
The only sound emitted was a bzzzzzzzzzzzzzzz like a "wonderful" short somewhere in the circuit. AARRRGGHH!
After triple check of components and a night past over the pcb I found no errors in connections.
I was sure that the pt2399 was working well as i used to hear behind the bzzzz the echo.
I also tried to change one operational (4558) with other 2 similar.

At the end I discovered that the problem was due to the lfo operational..
I discovered also that the 2 others 4558 that I tried to change  was shorted

I was so mad... I was getting literal crazy.
3 operational broken from the start... never happened before... (Hope nevermore)

After replacing the lfo op the sound It's ok.
It has a good sound..
The repeats become a little  "harsh" as you increase the speed pot (after 500ms).  but It's ok, it's like my others reb2.5.
I like a lot the tail switch tail... It is a wonderful idea (useful to me)
(feedback pot too big, I'll replace with another one like 25k)

The LFO modulation is a strange point. After a while I found a good setting.
I see that the depth pot affect the speed of the repeats of the pt2399.
Maybe as I use a bigger pot than the one in the scheme could it be the cause?! Infact at that position the depth is too deep... and become a strange funny fx that bends the notes played.

Now I'm happy of my new delay. So now I 've 4 delays in my fx chain: rebo1e 2.5 - rebo2e 2.5 - the danelectro reel echo.... and the echo base that I will call "The last Echo" (I like p.floyd sound so now I can become crazy with all those delays )
Another good fx after my other builts: Rat, Small clone chorus, 2 ts808, phase90 and tube amp P1-ex.

Bye and thanks at all, I'll be around this forum for long time.
Paolo R