anderton bi-filter

[thomas2]

hi.. now it's time for a really stupid question...
i'm trying to build the anderton bi-filter from generalguitargadgets site..
i was wondering.. can i substitute the two opamps (TLO72) with something else like 4558 or TLO82?`and do the diodes have to be 1N4001.. could i use 4148 instead? it's kinda difficult to get the right parts around here.. and expensive..

[Alpha579]

yeh, you could swap the opamp, but id try and keep the diode a recifier diode. I always replace 1n4001 with 1n4007...

[jsleep]

I need to update that layout!  There's a mistake on there.  I don't remember off the top of my head where it is, but it's in the upper left section of the layout.  I'll look into it and post again the error can be easily overcome with a jumper.  Be back to you on this.

JD Sleep

[Paul Perry (Frostwave)]

Mark hammer had a mod to this, which you can see at JC Maillet's site http://www.lynx.bc.ca/~jc/pedalsBiFilter.html
Personally, looking at the ckt there, I think you could leave out the diodes at the battery side (they are protection against reverse polarity), and the remaining diode could be anything at all, so far as I can see.

[jsleep]

Here's the fix you need to do to the layout (if you are using it).  Schematics are correct!!!!


On the layout R17 is attatched to the wrong end of C1.  You need to break the trace between R17 and C1, then run a jumper from that end of R17 to the junction of C1, R10 R18, IC2-pin2.

I'll fix this when I get a chance, but I really need to redraw a whole new layout to include Mark's excellent mods, so it may take some time.

JD Sleep

[thomas2]

thank you mr. sleep..
i will do that tomorrow.. let's hope it will work.. i had to substitute many components because i didn't have the right ones.. (opamps, diodes and a few capacitors).. i tried to debug it with audio probe already but the signal only went to the first opamp and didn't come out at the output..