Ehx echoflanger repair

[aka180]

Hi all,
This is my first post so i apologize if it's too lengthy.
I picked up an old echoflanger that and I'm struggling to get it going. It was pretty hacked up when i got it with all of the wires missing, one of the opamps was removed, transformer was removed and an attempt to power it with an external power supply, some of the original trimpots were replaced and just a bunch of bad solders. I've finally managed to get it to power up and now can get a dry signal out of it. So far I've gone through this thread https://www.freestompboxes.org/viewtopic ... er&start=0 and followed the old hand written schematic linked on that thread.

This is what I've done so far:
Traced out the schematic and reconnected all the wiring to what i figured is correct.
Replaced the voltage regulator and wired it for 18vdc.
Put in a new 4558 beside the feedback pot. I'm pretty sure the other one is not the original either.
Found a broken pin on one of the 4053 IC's so just replaced them both.
The trimpot between the 1024 and the 4049 was not an original and was a 100k. I installed a 1k as indicated in the schematic. I understand though that some versions of the schematic do indicate it as 100k so I'm worried about that.
The power switch was missing so for now, i just jumpered it (red wires marked 11 and 12)
The actuator for the mode switch falls off so I'm waiting for a new one but the contacts seem to be ok.

Now then...here's what is happening:
Basically the effect itself is not working.
I'm getting my 15vdc supply. I get dry signal from both outputs when i activate the footswitch both ways. When i close the blend switch, there is no output unless i activate the footswitch to bypass.

Not sure what the next step is. I'm going to replace the other opamp. Judging by the bad job of soldering on the new parts, I'm thinking the previous owner fried it. I'm really starting to worry that none of the IC's are functional meaning it's pretty much scrap.

Any guidance would be greatly appreciated!

[Scruffie]

First of all, i'd suggest leaving in that opamp rather than going off a hunch.

You need to take voltages of all the ICs and post them.

Whatever you do, don't scrap it, if you decide to give in on it i'd be interested in purchasing it.

Oh and that trimmer should be 1k so you're okay there.

[aka180]

Thanks for your response!
Here are the voltages from each IC. I'm writing this on my cell so, i hope it's legible.

I was suspicious about the different readings on the SAD1024's but looking at the schematic it kind of make sense...
And i hope it doesn't come to it, but no worries, i won't just trash it

4558a
1) 7.69
2) 7.69
3) 7.69
4) 0
5) 7.1
6) 7.11
7) 7.1
8 ) 15.3

4558b
1) 7.61
2) 7.61
3) 7.61
4) 0
5) 7.7
6) 7.7
7) 7.7
8 ) 15.37

LM324
1) 7.58
2) 7.69
3) 7.62
4) 15.37
5) 7.69
6) 7.69
7) 7.69
8 ) 7.8 (fluctuates)
9) 7.69
10) 7.69
11) 0
12) 8 (fluctuates)
13) 7.69
14) 14

NE570
1) 0.9
2) 1.79
3) 1.79
4) 0
5) 1.79
6) 1.79
7) 7.12
8 ) 1.79
9) 1.79
10) 6.82
11) 6.89
12) 1.79
13) 15.37
14) 1.79
15) 1.79
16) 0

4053a
1) 7.68
2) 7.63
3) 7.7
4) 7.7
5) 7.7
6) 0
7) 0
8 ) 0
9) 2.6
10) 13.98
11) 2.6
12) 3.9
13) 3.9
14) 3.9
15) 7.68
16) 15.37

4053b
1) 7.8
2) 7.6
3) 7.6
4) 7.7
5) 1.8
6) 0
7) 0
8 0
9) 2.6
10) 13.5
11) 0
12) 7.69
13) 7.69
14) 7.68
15) 7.5
16) 15.37

1024a
1) 0
2) 6.75
3) 0
4) 0
5) 0
6) 0
7) 15.37
8 ) 0
9) 0
10) 6.75
11) 0
12) 0
13) 0
14) 0
15) 0
16) 15.37

1024
1) 0
2) 6.5
3) 0.
4) 0
5) 0
6) 15.36
7) 15.37
8 0
9) 0
10) 6.5
11) 0
12) 0
13) 15.36
14) 0
15) 0
16) 15.37

4049
1) 15.37
2) 0
3) 14.45
4) 0
5) 14.540
6) 0
7) 14.5
8 ) 0
9) 14.5
10) 0
11) 14.5
12) 0
13) 0
14) 14.5
15) 0
16) 15.36

CD4013
1) 14.2
2) 14.3
3) 15.3
4) 13.2
5) 14.4
6) 13.2
7) 13.2
8 ) 15.3
9) 13.2
10) 15.3
11) 13.2
12) 13.2
13) 13.2
14) 13.2

LM311
1) 0
2) 7.5
3) 6.2
4) 0
5) 15.3
6) 15.3
7) 15.3
8 ) 15.3

[Scruffie]

Right, there's a few things wrong there but it may be one part is causing the others to have issues.

But first of all, your 4013, it doesn't show any ground connection and nor is it getting proper voltage so i'd start with that and also testing the 1uf Tantalum from its supply pin (pin 14).

[aka180]

Code: Select all

So i just some got new IC's. I put in a new 4013 took the voltages again. I'm thinking this is progress but still not there I also check the capacitor but it was fine. The voltages also changed on the 4049 but that is is getting really hot now. I also checked the capacitor from pin 8 of the 4013...also fine

4049

1) 15.37
2) 3.5
3) 10.4
4) 3.5
5) 10.4
6) 3.6
7) 10.4
8 ) 0
9) 10.3
10) 3.6
11) 10.4
12) 3.6
13) 0
14) 10.4
15) 3.5
16) 15.36

CD4013

1) 10.3
2) 10.4
3) 6.6
4) 5.9
5) 10.3
6) 5.9
7) 5.9
5.9
9) 5.9
10) 5.9
11) 5.9
12) 5.9
13) 15.3
14) 15.3


LM311

1) 0
2) 7.5
3) 4.7
4) 0
5) 15.3
6) 15.3
7) 6.6
8 15.3

1024a

1) 0
2) 6.5
3) 3.5
4) 5
5) 5
6) 15.3
7) 3.4
8 15.3
9) 3.4
10) 5.6
11) 5.6
12) 5
13) 1
14) 3.4
15) 5.7
16) 0

1024b
1) 0
2) 5.7
3) 3.5
4) 1
5) 1
6) 15.3
7) 15.3
8 3.3
9) 15.3
10) 3
11) 1
12) 15.3
13) 1
14) 3.2
15) 5.7
16) 0

[Scruffie]

Well if the 4049 is getting hot replace that too, probably has an internal short.

You should check the 4013 has proper continuity to ground on pin 7 as well.

[aka180]

So I've been occupied with all kinds of other things this summer but i finally got around to working on this again. I'm very happy to say that it is working now! I found the ground issue you mentioned, there was a break in the lead in that cardboard strip thingy. I followed the signal path with a scope and found i lost signal at the second 1024a. I swapped positions of the 2 chips, fiddled with the trimpots and couldn't get anything out of the first one so i figured it was dead. I got a replacement for a shockingly high price on eBay, popped it in, tweaked it's trimpot and it's working.

I just need to replace the rotary switch. I ordered one but it wasn't the right one so I'm expecting the proper one next week.

Anyway, i just wanted to say thanks for all your help!
Cheers

[Dirk_Hendrik]

I'd almost say that actuator being held in place when the PCB is mounted in the case, and therefore coming off when out of the case, is normal. Mine does that too. And the others I fixed.... did that too.

[Scruffie]

I'd almost say that actuator being held in place when the PCB is mounted in the case, and therefore coming off when out of the case, is normal. Mine does that too. And the others I fixed.... did that too.

Yup, mine does that too and if it works, it works.

Glad you got it going again