Envelope Filter Tonepad - Reverse Sweep Problem

[Zipporello]

hi all

today i finish the tonepad envelope filter with all mods.
it works very well. except the revers sweep mod.

everytime i use this mod, it mute the signal.
i'm pretty sure the circuit and the solder is ok.

someone has the same problem?
how can i fix this problem?
(i actually use the standard CD4066 & CD4069 IC).

thanks 

[daverdave]

Sounds like a continuity problem. Check all the connections on either side of the switch, see where the signal stops, I'd audio probe the connections, might be a bad solder joint, duff switch etc.

[Joseeduardosn]

claro, primero intenta uniendo los cables físicamente para ver si funciona. Parece que el problema es el switch.

[Zipporello]

ok, i'll check soon.

someone has a schematic to how connect the switch for the reverse sweep?
maybe the problem is wrong connction on the switch.

thanks

[Zipporello]

no one want help me about the revers sweep switch?

[daverdave]

The schematic is on tonepad, the switch you should be using is a dpdt switch, make an audio probe using a mono jack and probe the input and output of the switch. Probe pin 9 of IC1 and then pin 8, see if the signal is getting through. Follow the signal through and see where it stops.

Use a multimeter set to continuity to check the switch works.

If there's no output, as I said before, it's likely and issue with the switch, either an open circuit on a solder joint, wired incorrectly or a duff switch.

[Zipporello]

thanks, like this? (the green wired is the reverse sweep)

[Skrogh]

You've got the points mixed up, I'm at school atm, but i can post the correct wiring when I get home.

[Zipporello]

Really thanks, i'll waiting for it. 

[Skrogh]

Here you go:


Edit:
woops the resonance pot will work in reverse as it is here... flip the wires to E and F and you'll get more resonance(peaky filter) as you turn the pot clockwise

[Mark Hammer]

Note that the reverse sweep (which we can thank Steve Giles for) is the simplest possible reverse one can do.  I have found that it sounds bad if you set the Attack time too fast.  You need to back off the attack time a bit.

Also note that when you see filter pedals with up+down sweep, the downward sweep is usually adjusted to start from somewhere below the top of the range, because starting from the very top doesn't sound very good.  The reverse sweep on the EF starts from the complete opposite end (very top of sweep).  We need to come up with some way of getting it to start the downward sweep a little lower.

[Zipporello]

Damn...i've totally mixed up it.
Really thanks to everybody.

Stefano