Magnus Modulus Issue

[DaSt]

Hi,

I just built that one: http://tagboardeffects.blogspot.fr/2013/04/magnus-modulus.html

At first i had modulation working but no tremolo not delay. After checking for bridge and scoring between tracks I now have delay perfectly working but no tremolo nor modulation.

The rate LED works as expected and its glow is modulated by space/Rate/Smooth/depth as expected.

Here are the voltages I have on the chips :

NE5532
1 - 4
2 - 9.11
3 - 3.78
4 - 4
5 - 3.73
6 - 4
7 - 0
8 - 3.97

TL062
1 - between 4.45 and 6.6
2 - 9.11
3 - between 4.45 and 6.6
4 - between 3 and 7
5 - between 4.45 and 6.6
6 - 6.81
7 - 0
8 - between 3 and 7

When engaged the tremolo or modulation switch do not change the sound at all. Anyway the time pulse is heard faintly, and can be loud when feedback is at max.

Already checked for bridges many times and also checked the wiring.

Any idea where I could begin to troubleshoot that ?

Thanks !

[Travis]

Are you testing this in the dark or in the light? I think you're gonna want to be checking around the LDR. Sounds like the LFO is working fine but something is wrong with the LDR

[DaSt]

By LDR i'm assuming you speak about the J201 ? In that case I don't see the relation with ambient light ?

I'll try another J201 as I have a few left, but what bothers me is that at the beginning modulation was working and not delay, now the opposite (trem never worked)

[Travis]

No an LDR is a light dependent resistor. If you didn't install that then the modulation won't do anything

[IvIark]

Just to avoid confusion I think you have your IC numbering in the wrong order.  The conventional numbering which people will always assume is:

1 --- 8
2 --- 7
3 --- 6
4 --- 5

The PT2399 voltages will also tell us a lot more, or at least it will as far as the delay is concerned.  So the voltages of those pins will really help.

Have you tried a second PT2399?

[DaSt]

Hi,

My bad, here is the voltage again with the right pinout and the 2399. I didn't swap it as i don't have any spare :

NE5532
1 - 4
2 - 3.78
3 - 3.73
4 - 0
5 - 3.97
6 - 4
7 - 4
8 - 9.11

TL062
1 - between 4.45 and 6.6
2 - between 4.45 and 6.6
3 - between 4.45 and 6.6
4 - 0
5 - between 3 and 7
6 - 6.81
7 - between 3 and 7
8 - 9.11

PT2399
1 - 4.96
2 - 2.48
3 - 0
4 - 0
5 - 2.73
6 - 2.48
7 - 0.6
8 - 0.77
9 - 2.48
10 - 2.50
11 - 2.45
12 - 2.48
13 - 2.50
14 - 2.48
15 - 0
16 - 2.50

Thanks!

[DaSt]

@ Travis yes I know what a LDR is, i just don't see any on the layout. In the description there is a not saying we could use one but here a J201 was used instead. Or am i dead wrong ?

[DaSt]

Hi,

I try 4 different J201 without any success.

Anyway now the modulation section works perfectly, without me doing anything about it.. Just deboxing and reboxing it from the wood box i use for tests.

When engaged a faint high pitch tone can be heard no matter the effect engaged afterwards. When Tremolo is engaged a faint hum can also be heard.

Any idea where I could begin troubleshooting the tremolo ?

Thanks !

[DaSt]

Hey,

I'm still stuck and really can't get anything from that tremolo part. Not a switch issue (i use DPDT stomp and tried bypassing it first thing).

Any help at all ? Are my voltages about right ?

Thanks