Dimension P - New PT2399 Chorus

[bluebunny]

All the schematics were re-posted just a few centimetres above your post, Benoit.

[Kevin Mitchell]

All the schematics were re-posted just a few centimetres above your post, Benoit.

Marc's home office


Only foolin'.
I didn't even know this project existed! Looks interesting!

[bluebunny]

If only my home office looked that neat...   

[Phend]

Looks like my next build, thanks much. Fuzzed out at the moment, (ha never).
But a few questions on the circuit v1.1 modded.
1) Will 1n914 work in place of 1n4148 ?
2) The 1/2 voices switch and dry on/off switch.  Are these two separate SPST switches ?
3) Beginner question about TL072 pinout numbers, I see the two halves.
    Are these number correct ?
    Starting at the right tit and going CCW.
    U1a : 1 , 8, 2, 5, 4 (gnd)
    U1b : 7, 6, 3 (5v)
Regards
Paul
   

[Kevin Mitchell]

Looks like my next build, thanks much. Fuzzed out at the moment, (ha never).
But a few questions on the circuit v1.1 modded.
1) Will 1n914 work in place of 1n4148 ?
2) The 1/2 voices switch and dry on/off switch.  Are these two separate SPST switches ?
3) Beginner question about TL072 pinout numbers, I see the two halves.
    Are these number correct ?
    Starting at the right tit and going CCW.
    U1a : 1 , 8, 2, 5, 4 (gnd)
    U1b : 7, 6, 3 (5v)
Regards
Paul
   

1) yes, every time you see 1n914 you can use a 1n4148 instead
2) I'd say yes they are two SPST switches. Otherwise you wouldn't be able to set it to the default unmodded format. But really it would be better to use a single DP3T switch to handle both - I'd guess that was the original thought.
3) Best to view a dual opamp schematic as 3 sections. Channel A, B and power. There's nothing special about channel A vs channel B, as long as they are wired properly against the schematic (pos in, neg in & output).

[Phend]

Thanks Kevin,
So use 1n914 instead of 1n4148
And using 1/2 and other 1/2 of TL072 becomes:

Correct ?, (sorry for being slow)

[Kevin Mitchell]

So use 1n914 instead of 1n4148

Oops I had it backwards. But yeah those diodes are interchangeable. This is a popular notion.
Opamp pinouts look good!

[Phend]

Great, thanks Kevin, plus I have an on on on dpdt switch from a previous build order. 
Always always buy a few extra of those low cost components, you will find a way or need to use them.

[bluebunny]

I've built this three times.  I used two SPSTs for the dry/wet and 1/2 voice options.  I've got one in the pipeline with a 2P4T rotary, just to confuse things a little.

[Phend]

Darn, no more changes

[bluebunny]

To assuage Paul's despair, the 2P4T is a solution to a problem (steel enclosure with three pot holes pre-punched - I ain't drillin' me no steel!).

[Phend]

Does the 4th position turn both sws to off ?

[Phend]

I'll pass , Amazon has these , no idea what the gift card deal is about

[bluebunny]

Does the 4th position turn both sws to off ?

Yes.  So you have:

voices |   dry on    |   dry off
   2   | rich chorus | weird vibrato
   1   | thin chorus |    vibrato

[Phend]

I won't pass, will get a 2P4T rotary.
Connect center A B pole pins to "out"
Connect 2 adjacent pins on one side to R23 (dry)
Connect 2 middle pins on the other side to R24 (voices)
Four other pins have nc
Simple enough if my "assumed" hand drawn diagram is correct.