Hi Guys
Happy new year to all.
So i received today my pt2399 and jump on the delay! yeaaaaa
First time no sound just static and some delay noise on the background... but no guitar signal
checked the pcb and find a bridge... :(
after solving that issue put it all together again and.... guitar signal but no delay!!
I´m using a 22k pot on the mix because i only have at the moment 2x50k pots! But i think that sould not be the problem!
voltages on the ics:
PT2399
1: 4,94
2: 2,36
3: 1,7mv
4:0,11
5: 2,86
6: 2, 38
7: 0,26
8: 0,79
9: 2,39
10: 2,38
11: 2,38
12: 2,38
13: 2,38
14: 2,38
15: 2,38
16: 2,38
on the Tl
1:3
2:3,02 (some hum when probing)
3:3
4:1mv
5:6v
6:3
7:3,02 ( some hum when probing)
8:3
As i told the first time i turn it on i had no guitar signal but mixing with the pots i can ear some delay changes on the static sound... but after i solved the bridge i mix the pots and nothing. just the guitar signal
I changed with a new pt and i have the same result
any ideas? a fault pt? bridge caused some damage on some components?
You definitely have issues. The TL072 should have 9V on pin 8, 0V on pin4, and about 4.5V on pins 1-3 and 5-7. Sorting out why you have 6V on your ground should be the first thing you do.
Jacob
Looks like you probed the pins wrong on the TL072. They go like this:
1 8
2 7
3 6
4 5
It looks like you have 6v on pin 8, which looks like a low battery. All your other pins are reading half that, which is good.
Try a fresh bettery or use a power supply and see if you get sound.
the regulator is an L7805cv
1: 4,96
2: 1,8mv
3:6,05
Quote from: midwayfair on January 02, 2013, 08:31:06 PM
Looks like you probed the pins wrong on the TL072. They go like this:
1 8
2 7
3 6
4 5
It looks like you have 6v on pin 8, which looks like a low battery. All your other pins are reading half that, which is good.
Try a fresh bettery or use a power supply and see if you get sound.
ok this is correct reading
1: 3 8:6
2: 3 7:3
3: 3 6:3
4: 1mv 5:3
the battery that i´m using on this moment as 8v
Verify that R7 is 33R, not 33K.
Double check that R20 and R21 are both 10K.
Verify the orientation of D1.
There are a limited number of things between your voltage source and pin8. Get that right first.
Pictures would help. Audio probing will as well. Figure out where you're losing signal.
i will check the things you point.
I have sound but a clean sound... no delay.
try jumping pins 3 and 4 together on the pt2399 and then power up the pedal
If I had a dollar for every sea urchin that fixed I'd be a few dollars richer ;)
i´m checking all components ::)
the c16 indicated by MB build list is a 47pf and the one that i have on the board as the inscription 472k
i checked on a conversion tab and this should be an 470k to get the 47pf.. and not the 472k
i´m thinking right?
i used this chart
http://www.turretboards.com/capacitor_conversion_chart.htm (http://www.turretboards.com/capacitor_conversion_chart.htm)
acording to this:
MB C16 value
uf: 0.000047 pf: 47 nf: 0.047 k: 470K
My C16
uf: 0.0047 pf: 4700 nf: 4.7 k: 472K
Quote from: gtr2 on January 02, 2013, 09:20:53 PM
try jumping pins 3 and 4 together on the pt2399 and then power up the pedal
If I had a dollar for every sea urchin that fixed I'd be a few dollars richer ;)
try this, but also unplug your power first. For me, it only worked when there wasn't power going to the IC to begin with
one doubt: jumper the 3 and 4 pin and leave it like that forever? Solder a jumper?
and what about the c16?
Quote from: gtangas on January 03, 2013, 02:05:07 AM
one doubt: jumper the 3 and 4 pin and leave it like that forever? Solder a jumper?
and what about the c16?
yes if that solves the problem
Quote from: gtangas on January 02, 2013, 10:58:52 PM
i´m checking all components ::)
the c16 indicated by MB build list is a 47pf and the one that i have on the board as the inscription 472k
i checked on a conversion tab and this should be an 470k to get the 47pf.. and not the 472k
i´m thinking right?
Re C16
472 = 4.7nF. You're correct that 47 (or 470) will be 47pF.
That's something that should be fixed, because it's going to significantly darken your tone, but it will not cause you to lose signal to the delay. If you check the schematic, you'll see that the delay is tapped from the output of the first half of the op amp; the clean signal moves on to the output buffer, and the delay does its thing and is mixed back in.
If you are truly getting amplified signal from your op amp, then your problem lies somewhere in the PT2399 section of the pedal. Jumper the grounds first (Josh has lots of experience with these and it's a good suggestion!); reflow your solder points, and get out the audio probe to figure out where the signal is being lost. The audio probe is your best friend at this point.
I had the exact same problem with my Sea Urchin. Delay worked intermittently. When it didn't, I noticed ~1.4V on pin 4. I jumpered pins 3 and 4 and the problem was solved.
solved! I have a nice delay! yesssssss
So far no need to jumper the 3 and 4 pin.
when i was taking care of the bridge a small piece of solder attached to the board causing another bridge that i didn't notice... so no delay! AGAIN! F****
But checking again i saw that bitch and.... voila! "Houston we have delay"
the sound comes out with a bit of interference noises but i´m supposing that is from the fact of everything is out of the box...
its a learn process i guess!
need some advice for a nice reverb... any advices?
Great!
I'd recommend anything using the new belton brick.
I sell the rub-a-dub but there are a few other projects rolling around.
Josh
Quote from: gtangas on January 04, 2013, 01:06:28 AM
need some advice for a nice reverb... any advices?
The Rub-A-Dub is an extremely good and simple "brick" delay. I've built two now (one for me and one for a friend) and I really like it. Absolutely no noise - it's quieter than my amp's verb. It does have some issues handling larger input signals, though, so if you use a lot of boosts or loud overdrives in-line, or don't have an effects loop, you may get some op-amp distortion.
GrindCustoms and CultureJam have the Tenebrion coming out soon. It's three knobs, but it can do near-infinite dwell and supposedly cannot be overdriven. It looks and sounds quite good and I'm excited to build it.
MerlinB (on DIYSB) has two reverb projects, the Solstice and the Equinox, that use two PT2399s. This would give you a little more optional control over some parameters, and the Solstice in particular sounds really good. They're not difficult to build but they're a
little more complicated overall than anything using the brick.
I went for the merlinb reverb.
From the samples I found on diystomp I have chosse the equinox....
Ad some trouble on the Pcb but it's done.... Noob issues lol
I sold my crate vintage club and bought the tubemeister 18 o doesn't have reverb.
I have to box it
It's a nice reverb.. It's a big Pcb compared with the Madbean stuff
Next project.... 1wt amp by chinchen. :-*
Hello to everyone on here!
I've been checking this forum out for quite some time now, but never actually posted anything. I figured I'd use this thread, since I have a similar problem as gtangas.
So I etched my own PCB (not all that clean as you can see in the photo), soldered everything and fired it up. All I got was clean signal, so I started debugging and saw that I must have a solder bridge somewhere, since my ground reads the same as battery. I found nothing, but I still have 8,4 V on ground with or without the ICs in the sockets. I tried jumping pins 3 and 4, and since then R7 is getting really hot, even without the jumper installed. I replaced R7, but it's still heating up badly. I wanted to post IC voltage readings, but can't for fear of burning something out.
So I turn to anyone that could help me, your help would be greatly appreciated, since I am no electronics wiz.
Also, I didn't have a 1n4001, so I used a 1n4007, R15 is a 4,7k, R11 and R17 are 22k and the jumper ic currently missing but the rest I think are as in the parts list.
So here are the links to the photos:
(http://shrani.si/t/2F/M1/4qHm2P1K/dsc02629.jpg) (http://shrani.si/?2F/M1/4qHm2P1K/dsc02629.jpg)
(http://shrani.si/t/3N/LV/4sGbuJ4v/dsc02638.jpg) (http://shrani.si/?3N/LV/4sGbuJ4v/dsc02638.jpg)
(http://shrani.si/t/1f/7v/jtGP6ut/dsc02633.jpg) (http://shrani.si/?1f/7v/jtGP6ut/dsc02633.jpg)
(http://shrani.si/t/1W/F8/Hx0k2zU/dsc02631.jpg) (http://shrani.si/?1W/F8/Hx0k2zU/dsc02631.jpg)
(http://shrani.si/t/25/TW/3xrFv9ZO/dsc02639.jpg) (http://shrani.si/?25/TW/3xrFv9ZO/dsc02639.jpg)
(http://shrani.si/t/3i/Ig/YSp7TXA/dsc02640.jpg) (http://shrani.si/?3i/Ig/YSp7TXA/dsc02640.jpg)
edit: could the reason for ground voltage be a malfunctioning capacitator?
Thanks again,
Miha
have you solved your problem?
my noob advice is to etch a new board! that one is very addicted to problems! :)
when i want to look for bridges i use a lamp behind the board that helps a lot.
what as the process of etching you use?
Hi everyone, I have a problem with this project.
When I switch on the power supply, the effect works properly, but when I switch off the power source and after few seconds switch on again, there is no delay effect but just the dry signal.
So i make a little short circuit in C2 and the effect starts to work.
I've tested the voltage of the L78L05. When the effect works properly, i read 9v input, 0v ground, 5v output. When the problem appears, i read 7v input, 0v ground, 5v output. Just a little short on c2 and the effect works properly with 9v input.
I've try to change the pt2399, the L78L05 and the power supply, I've also checked the tracks and the solders, but the problem still stays.
Any suggestion?
Thanks
Yes...
Put a jumper between pin 3 and 4 of the pt2399
Both are ground. My Last urchin did the same thing and it solved the issue
I read here in the forum that some guys install this jumper on every urchin build.
Report to us
thanks! i will try and than i let you know
I have just another question.
The part's list says to use a 7805; i've used a L78L05 (from taydaelec.). Is it the same thing?
Thanks
The 78L05 is the right part. The BOM is missing the L
Iap I use the same regulator... No issues
You can buy the big one with the heat dissipador or the small one with the same shape as an tran
Pick a left over of a component, resistor, cap, and make a jumper between pin 3 and 4..... You will see that it solves the problem
Josh told me that and it works like a charm
Next delay you have to build is a multiplex... Urchin is nice.... Multiplex is OMG...
The board is a beautiful piece of art
Sérgio
Thanks gtangas and gtr2 for your answers and tips, problem solved! Yahoooooo!!!
Josh is the one to give thanks.... He teach me lol
Sérgio
Hey, thanks for your help, but I solved the problem a few days after I posted this thing. There was a bad solder causing the failure, the etch was ok
now it's boxed up together with a lpb1 circuit in front of it and it works really nicely :)