Farfisa Repeat/Volume

theehman · Post by **theehman** » 04 Feb 2013, 14:31

Here's a monster of a pedal for you: the Farfisa Repeat/Volume. It's a Repeat Percussion effect with treadle-varied Rate that switches to a Volume pedal. I've had this for quite a while but I think I'm going to Ebay it or something so I figured I'd post some pics for you guys first. I have no schematic just yet but I'll see if I can work one up later today.

jreeves47 · Post by **jreeves47** » 04 Feb 2013, 14:33

Very cool! I want

flatcrabs · Post by **flatcrabs** » 04 Feb 2013, 19:10

does this one use the 2n2646 like the Vox?

theehman · Post by **theehman** » 04 Feb 2013, 20:17

flatcrabs wrote:does this one use the 2n2646 like the Vox?

No, it's a 2N2160.

Schematic nearly done.

theehman · Post by **theehman** » 05 Feb 2013, 14:05

Just realized I forgot to include the 10uF cap on the Unijunction. Please replace your schematic with this one:

flatcrabs · Post by **flatcrabs** » 05 Feb 2013, 14:39

Ron-

Thanks for the scheme! Does the Farfisa sound any different from the Vox?

theehman · Post by **theehman** » 05 Feb 2013, 16:50

flatcrabs wrote:Ron-

Thanks for the scheme! Does the Farfisa sound any different from the Vox?

It's about the same, maybe just a bit softer on the percussion.

Vintagekey1975 · Post by **Vintagekey1975** » 11 Jan 2015, 20:24

Firstly apologies for dredging up a two year old thread but thankyou to the original poster this is really helpful to me.

I have a Mk1 Farfisa Compact Duo which lacks the repeat function that the later model had, so I am going to build this circuit to give me the extra function that Pink Floyd used on their later Farfisa.

My question was regarding the power supply to this circuit if anyone can help. Can I use a Boss type 9vdc adapter rather than a battery or will I need to add any current limiting components.

Best

Dave

tube-exorcist · Post by **tube-exorcist** » 11 Jan 2015, 21:05

Vintagekey1975 wrote:Firstly apologies for dredging up a two year old thread but thankyou to the original poster this is really helpful to me.

I have a Mk1 Farfisa Compact Duo which lacks the repeat function that the later model had, so I am going to build this circuit to give me the extra function that Pink Floyd used on their later Farfisa.

My question was regarding the power supply to this circuit if anyone can help. Can I use a Boss type 9vdc adapter rather than a battery or will I need to add any current limiting components.

Best

Dave

You can use a Boss adapter (or any 9V DC power supply) but I believe that you will be disappointed. The Farfisa Compact Duo "Repeat Percussion" function is completely different (made with a glow lamp and a LDR).

Vintagekey1975 · Post by **Vintagekey1975** » 12 Jan 2015, 21:26

That's a shame. I tried the North Effects repeat percussion but it was too noisy and different. The closest I have gotten is with a maxed out Boss TR-2. I will probably build this circuit any way just for sh!ts and giggles. A Compact Duo through a "gating effect" like the repeat and then through a vintage Small Stone Phaser sounds fantastic. I will have to go the whole hog and get a Mark II Compact Duo.

Vintagekey1975 · Post by **Vintagekey1975** » 17 Jan 2015, 19:16

I'm rounding up components to build this circuit and just have the non electrolytic caps left to source. I wanted to check the values of them as I cannot find a 4700uF film cap anywhere. Are these in pF whereas the e-caps are in uF? I can clearly see 4700/10 on the cap in question in the photo.
Thanks again
Dave

theehman · Post by **theehman** » 17 Jan 2015, 20:46

Vintagekey1975 wrote:I'm rounding up components to build this circuit and just have the non electrolytic caps left to source. I wanted to check the values of them as I cannot find a 4700uF film cap anywhere. Are these in pF whereas the e-caps are in uF? I can clearly see 4700/10 on the cap in question in the photo.
Thanks again
Dave

I'd assume that since I didn't put a polarity mark on it that it's 4700pF. I no longer have the unit to check.

Vintagekey1975 · Post by **Vintagekey1975** » 23 Jun 2015, 20:07

Once again apologies for dragging up an old thread. I am in the middle of building this circuit and have a little confusion over the 470K/100K rate pot symbol in the schematic. Could somebody explain to me whether I need a 470K or 100K pot with the other value being a fixed resistor?

Many thanks in advance
Dave.

Nocentelli · Post by **Nocentelli** » 24 Jun 2015, 06:03

It appears to be a 100k pot with the wiper tied to one end (i.e. variable resistor) and a 470k in parallel with this variable 100k: I'm going to guess that this gives a taper that is more like reverse log, whichbtends to be more useful in rate controls (finer control at higher speeds).

Farfisa Repeat/Volume [schematic]