Farfisa strangeness.

[crow]

I recently acquired a Farfisa Mini-Compact organ, and love it. However, it has three issues. I'm about to open it up, but thought I'd post here in case anyone has experienced these before.

1) every note (seemingly) plays quietly and constantly. I'm guessing this is a cap issue. a friend says that all farfisas do this, but having heard a few that don't, i suppose it's just a common thing in these old things.

2) after a few minutes of being on, the "C" keys begin playing Bb's. all the other keys seem to play their correct note.

3) also after it's been on for a while, playing more than one C at a time results in a sputtering, distorted tone.

I'm hoping that it's just a bunch of aged caps, but hopefully i'll know more in a few hours.

[crow]

well, I opened her up and whew! that's a lot of capacitors. does anyone know what all of the trimpots along the back of the unit are? they are accessible by screwdriver through holes in the wooden exterior of the organ; i would suspect that they are for tuning, though i'm reticent to mess with them. oh well, what do i have to lose? here goes.

[Scodiddly]

The typical Farfisa organ isn't especially complicated on the component level, it's just that it needs a lot of stuff to generate each and every note. You should have 12 oscillator cards plus a few more for other stuff like power supply and filtering. Each note across the octaves (such as all the C's, all the Bb's, etc) come from a card which has a master oscillator for the top octave and divider circuits to produce the rest of the octaves for that note. So it's not surprising that your C's all become Bb's, you just have a problem with the C master oscillator.

Oddly enough I've never had to recap one - usually problems were caused by a bad transistor, easy enough to find because the top note might still be good but all the ones at and below the bad divider stage would be affected.

If you can't find service info anywhere I've got a small number of schematics.

[numberthirty]

You might want to check www.combo-organ.com. The spares and repairs section has some information on tuning and cleaning key contacts. I think there may even be an individual section on tuning specifics for various brands of organ.

[hiddendriveways]

You might want to check www.combo-organ.com. The spares and repairs section has some information on tuning and cleaning key contacts. I think there may even be an individual section on tuning specifics for various brands of organ.

nice site!

[crow]

Thanks everybody! On a side note that may interest you, #30, I'm trying to get this thing to behave because I'm going to sit in on keyboards etc. with Li'l Cap'n Travis at their CD release party on Saturday. It should be fun.

That being said, I also started cleaning out this old Moog/Cordovox "White Elephant" that I picked up a few months back and man, it's sounding pretty darn cool.

[crow]

You're right, Scodiddly. once I figured out how to get the dang chassis out of the case, it suddenly looked a lot more sensible. There is a leaky cap on the C card, and strangely, none of the other oscillator cards seem to have that cap. i'm about to replace it. hopefully, that'll be it.

[roygbiv]

This won't solve your detuning problem, and you may already know this, but some people don't, so here goes:

There is an expression bar that folds out under the organ.

You need to engage that (fold it out, and move to the right with your knee/other body part) to increase volume/treble.

If it is not engaged. the background whine from all the keys will relatively seem much louder.

Great organ - have fun!

[numberthirty]

Thanks everybody! On a side note that may interest you, #30, I'm trying to get this thing to behave because I'm going to sit in on keyboards etc. with Li'l Cap'n Travis at their CD release party on Saturday. It should be fun.

That being said, I also started cleaning out this old Moog/Cordovox "White Elephant" that I picked up a few months back and man, it's sounding pretty darn cool.

That is surely of interest. Is there any chance someone is going to sic some sort of recording mechanism on this show?

[crow]

recording? not that i know of. rest assured, it will sound exactly like the record. i've given up on the farfisa for now, and will be using the white elephant instead. it sounds great: it's a farfisa-style organ on the lower tier and a moog satellite on the upper. i can't get a few features to work (the filter on the satellite doesn't do anything and the "percussion" section of the organ also doesn't do anything), and it's enormous, but it's so much more fun to hear than my hammond xb-2.

back to the farfisa wierdness, i replaced several electrolytics, and no dice. after 5 minutes or so of being on, the c note begins freaking out. i messed with the tuning trimpot (inductor?)and strangely, if it's tuned to a different note (d or Bb, for example), the note behaves a lot better than if it's closer to C. when it's around C it really sounds crazy, like it's fighting with itself. when i have time, i'll just start replacing parts.

[Scodiddly]

Oh yeah, I forgot how annoying it is to get the guts out.

Anyway, the C card has an extra divider section, because there's one more octave of C than any other note.

[crow]

thanks, scodiddly. that makes sense.

i've started looking into replacing some transistors, and i see that almost all of them are labeled "SFT 352", with one on the C card reading "SYLVANIA ECG102A". Mouser's search engine didn't offer anything up in response to the latter, but it suggested the NTE 158 as a replacement for the former. does this sound right? i'm in a little over my head here; until now i've pretty much been a mindless re-capper. now i'm getting promoted to mindless re-transistorer, i guess.

[Scodiddly]

It's been a while, but the NTE replacement sounds right. I think that's what I always used, anyway. If you had a bunch to replace it might make sense to figure out a non-NTE replacement because it would be cheaper per transistor.

[crow]

i'll give it a shot; what do i have to lose?

There is an expression bar that folds out under the organ.

You need to engage that (fold it out, and move to the right with your knee/other body part) to increase volume/treble.

If it is not engaged. the background whine from all the keys will relatively seem much louder.

i had read that this only added the harsh "tone booster" sound to the mix, but how glad i am to be wrong, roygbiv! i think i'm going to try to modify this thing physically so that I can use it without the legs. this organ is a great size to go on top of a rhodes or wurly, so it'd be nice to not need the bar sticking out.

thanks for the advice, y'all. i've got to say that having access to the internet, and the folks on this forum in particular, sure takes a lot of the headache out of collecting and fixing old gear.

[Fac06]

You need to be REALLY carefull when tweaking the trimpots used for tuning a Farfisa/Vox etc as there is a good possibility they will break when you tweak them. Best to remove any wax or sealant that is around the place to put the screwdriver head and squirt the TINIEST amount of cramolin or tunercleaner in it first. Normally I do not reccomend squirting stuff in anything but for these you almost always have to as they usually have been stored in a basement, garage etc and the coils that make up the pots do not like moisture. Also use a PLASTIC/NYLON/NON METAL SCREWDRIVER or you will go insane trying to tune the divider cards!!!

I also have some Farfisa schemos for trade etc if you need them. I also have many transistor cross reference books that I will use to help those that are working on these types of organs- just email me but be reasonable in the amount of cross referencees as they can be lengthy!
I LOVE the Farfisas of the 60's and early 70's but you ALWAYS gotta use a noise gate on them especially for recording. I love working on them too but
I usually find that I have to use Lysol wipes on them as I am slightly allergic to mold....

MMmm..... Farfisa/Vox smell.....