Bixonic - Expandora

devastator · Post by **devastator** » 05 Aug 2008, 22:00

hi, my first post in this great forum!

I'm looking for some circuit pics of Bixonic's expandora, I found nothing so maybe you've that ?

Also, you think this schemo is correct ?

http://www.geofex.com/FX_images/expandor.gif

thanks!

-Devastator-

soulsonic · Post by **soulsonic** » 05 Aug 2008, 23:57

I have an original Bixonic Expandora. I haven't had a chance to open it up yet to verify Gus' schematic. Gus knows what he's doing, so I'm sure his schematic is correct, but still, it's nice to have photos to prove it. If I get a chance, I will try opening it up to verify and take pictures. I recall last time I looked in it, I was confused about how to remove the board because of how it's held in with the I/O jacks... anyone else here know what I'm talking about?

analogguru · Post by **analogguru** » 06 Aug 2008, 01:23

When you opened it, I believe it will have looked like the picture below.

analogguru

soulsonic · Post by **soulsonic** » 06 Aug 2008, 02:31

Yes, it looks exactly like that. I can't figure out how to remove the board. There's no room to slide the jacks out of the case mounting holes. It was very strange to me. I need to look at it again and see if there's something I missed.

lynessmy · Post by **lynessmy** » 06 Aug 2008, 03:02

I guess you need to desolder the jack before can take out the PCB....

soulsonic · Post by **soulsonic** » 06 Aug 2008, 03:54

lynessmy wrote:I guess you need to desolder the jack before can take out the PCB....

I suppose so. I don't understand why they would build it that way; but looking at it, I can see how the jacks may have been installed first, and then the board soldered to them.

Dirk_Hendrik · Post by **Dirk_Hendrik** » 06 Aug 2008, 08:19

soulsonic wrote: I suppose so. I don't understand why they would build it that way

Easy and cheaper construction. Saves the time to strip and solder wires and holds the board in place at the same time. Provided there's a proper mechanical strain relief on the jacks, so no tension on the solder joints when inserting a plug, there's nothing wrong with that construction. Tech21, as an example, does the same.

guiltyspark · Post by **guiltyspark** » 06 Aug 2008, 10:51

soulsonic wrote:Yes, it looks exactly like that. I can't figure out how to remove the board. There's no room to slide the jacks out of the case mounting holes. It was very strange to me. I need to look at it again and see if there's something I missed.

I had the same problem. A while back I was thinking of modding one for more low end but couldn't get the board out. Figured out the jacks have to come off and it looked like a hassle so I moved on. I kind of like the basic tone but they always seemed a little thin sounding to me.

Guiltyspark

soulsonic · Post by **soulsonic** » 06 Aug 2008, 14:25

The thing that always bothered me was how mushy it is at high-gain settings. At low drive settings, I think it sounds great, but at high gain, everything just splats out. It would be nice to see if that could be tamed a little bit.

gus · Post by **gus** » 06 Aug 2008, 23:53

A friend had one that they needed that same day. I only had a few hours to fix it and trace it so the schematic might have an error(s). (dirty contact(s)IIRC). I unsoldered. the jacks to remove the board. IIRC the board is a quality one so if your unsoldering skills are good you should have no problem with the pads

Post by **modman** » 07 Aug 2008, 00:31

: thanks for letting us know, Gus!

soulsonic wrote:I have an original Bixonic Expandora. I haven't had a chance to open it up yet to verify Gus' schematic. Gus knows what he's doing

But the internet doesn't, and eats the reservations that accompanied the drawing initially. It would be very nice if we could set the record straight on this one... when you get around to it, Soulsonic

Whoismarykelly · Post by **Whoismarykelly** » 07 Aug 2008, 05:16

Seriously guys? The unrelenting clone train that is FSB.org is being ground to a halt by some jacks that are soldered to the board? Screw goop. Why isn't everyone else just using board mounted jacks?

Dirk_Hendrik · Post by **Dirk_Hendrik** » 07 Aug 2008, 06:43

Whoismarykelly wrote:Seriously guys? The unrelenting clone train that is FSB.org is being ground to a halt by some jacks that are soldered to the board?

If that seems to be the case to you. So be it. No problem. Byebye.

eleanor296 · Post by **eleanor296** » 07 Aug 2008, 15:17

Dirk_Hendrik wrote:
Whoismarykelly wrote:Seriously guys? The unrelenting clone train that is FSB.org is being ground to a halt by some jacks that are soldered to the board?
If that seems to be the case to you. So be it. No problem. Byebye.

... I think he was joking....

Whoismarykelly · Post by **Whoismarykelly** » 08 Aug 2008, 04:12

eleanor296 wrote:
Dirk_Hendrik wrote:
Whoismarykelly wrote:Seriously guys? The unrelenting clone train that is FSB.org is being ground to a halt by some jacks that are soldered to the board?
If that seems to be the case to you. So be it. No problem. Byebye.
... I think he was joking....

I was indeed. I mean, it is funny though that the same guys that can chip away at goop for hours on end wont desolder some jacks to get into a pedal.

soulsonic · Post by **soulsonic** » 10 Sep 2008, 00:57

Well, I finally took the time to tear it apart.

: Bixonic Expandora

Initial inspection looks like Gus' original schematic is right on. So far the only thing I've seen different is a diode marked as a "?" in the scheme is a Zener.

sevinisthenumber · Post by **sevinisthenumber** » 23 Jan 2009, 18:32

Anyone know any mods for this unit?

Post by **sidehatch** » 25 Jan 2009, 07:18

Of all the 100's of distortion pedals i have bought and sold this is the one I regret.The distortion and forbidden settings are awesome.

I sold it becaucse of a loud pop I got when engaging the pedal. It drove me nuts. This was before True bypass loopers were popluar. I spoke with many owners an I was the only guy that had that problem.

They werent all like that one. I need to find another or get a clone thats not in a can and is handwired...

MKB · Post by **MKB** » 25 Jan 2009, 13:06

soulsonic wrote:
lynessmy wrote:I guess you need to desolder the jack before can take out the PCB....
I suppose so. I don't understand why they would build it that way; but looking at it, I can see how the jacks may have been installed first, and then the board soldered to them.

Actually that's a very good and reliable way (maybe the only way) to allow PCB mount jacks that also fasten to opposite sides of a case. If you bolt down the jacks then solder them to the PCB, you can eliminate strain on the solder joints that can cause joint failure in the future. If you solder the jacks on the PCB then bolt them into the case, the solder joints on the jack will be under a lot of strain.

I breadboarded one of these from the internet schematic a few years ago, it is a very clever design. The main tweak is an expander circuit that allows higher amounts of drive when you hit the strings hard, and lower amounts with light picking. It exaggerates your picking style. Very cool.

soulsonic · Post by **soulsonic** » 25 Jan 2009, 21:43

Anyone ever find one of those Sharp optos? It's an optocoupler that uses a JFET. I found the datasheet, but so far I haven't found any substitutes with the same resistance range.

I wonder what the new Expandoras use?

Bixonic - Expandora [traced]