Joyo - JF-05 Classic Chorus  [schematic]

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greeny23
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Post by greeny23 »

Borrowed this thing from a friend of mine to look at. Having seen the guts of the joyo OD and ultimatedrive i was lead to believe they have pretty good workmanship.

Seems the classic chorus is the exception.

Image

Offboard components?

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Burnt soldering?

Image

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Maybe i just got a bad one, anyone got a comparison?
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Post by Lawnchair »

holy shit assembled by a 4 year old. Child labor laws damnit!

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Barcode
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Post by Barcode »

The leads on the ICs are oxidized. It looks to me less like workmanship issues and more like someone did some damage.

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Post by Ice-9 »

If you look on the other side of the board, right under where that reisitor is soldered you will see a place for a resistor which is missing. That looks like a repair and whoever did it was probs not able to replace the resistor on the component side so just soldered it to the back of the board. The brown markings around this solder joint is flux from the solder, just needs a clean.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

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Post by Hides-His-Eyes »

I'm suspect too. The others we've seen were clearly wave soldered. You can't really cock that up.
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Post by Hides-His-Eyes »

That said, we're taking bets on whether that underside electro is to stop LFO tick or clock noise ;)
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Post by atreidesheir »

It looks like it has been exposed to salt water to me.
Perhaps in Pacific transport? Look at those pots. Looks relic'ed to me.
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Post by Steven_M »

Yeah, I think this is an anomaly. All the joyo's I have seen have only had three common problems:

1) Parts not flat against the board. (Cosmetic)
2) Switch wiring a little light on solder. (Easy Fix)
3) General dirt/detritus on the boards. (Not a deal breaker)

I've never seen flux residue/Oxidation on any of their other pedals, and I've seen inside a lot of Freekish Blues pedals!

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Post by Dirk_Hendrik »

Steven_M wrote:Yeah, I think this is an anomaly. All the joyo's I have seen have only had three common problems:

1) Parts not flat against the board. (Cosmetic)
2) Switch wiring a little light on solder. (Easy Fix)
3) General dirt/detritus on the boards. (Not a deal breaker)

I've never seen flux residue/Oxidation on any of their other pedals, and I've seen inside a lot of Freekish Blues pedals!
+1.
Other than that that "salt water" is flux residue too. Boards not washed after wave soldering.
That resistor + flux junk may be a Joyo mod just as well. What are you're going to do when you find an error after a production run of a couple of thousands of pedals? You find a fix and hire a low paid soldering chick. Cleaning up flux is not really required (IPC J-std class 1 case) and takes much more time than soldering that one resistor.

Bottom line,
It might not be that good.... but it's bloody much better than the soldering in an average (wannabee) boohteek pedal (what is flux anyway?)
Sorry. Plain out of planes.

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Post by Steven_M »

Dirk_Hendrik wrote:
Bottom line,
It might not be that good.... but it's bloody much better than the soldering in an average (wannabee) boohteek pedal (what is flux anyway?)
Indeed! Compare the soldering on the backside of this board with ANY of the soldering mods on the Freekish Blues stuff. I know who I would rather have tinkering with my pedals: J. Wong!

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Post by Dirk_Hendrik »

Steven_M wrote:
Dirk_Hendrik wrote:
Bottom line,
It might not be that good.... but it's bloody much better than the soldering in an average (wannabee) boohteek pedal (what is flux anyway?)
Indeed! Compare the soldering on the backside of this board with ANY of the soldering mods on the Freekish Blues stuff. I know who I would rather have tinkering with my pedals: J. Wong!
Uuuh,
You're implying FB being boohteek!? :scratch:


;)
Sorry. Plain out of planes.

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Post by Steven_M »

Dirk_Hendrik wrote:
Steven_M wrote:
Dirk_Hendrik wrote:
Bottom line,
It might not be that good.... but it's bloody much better than the soldering in an average (wannabee) boohteek pedal (what is flux anyway?)
Indeed! Compare the soldering on the backside of this board with ANY of the soldering mods on the Freekish Blues stuff. I know who I would rather have tinkering with my pedals: J. Wong!
Uuuh,
You're implying FB being boohteek!? :scratch:


;)
I'm implying that FB is Wannabe Boutique for sure, not Boutique, Boutique.

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Post by rocklander »

I want to post in this thread so that Dirk will thank me too.
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Post by greeny23 »

a little update-
both underside components are running in parallel to resistors.. not replacements. the resistor missing is just plain missing.. the pedal is brand new from the factory.

man these guys confuse me!
the toyroom effects guy.

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Post by ZombusWoof »

I modded an ultimate overdrive that had a capacitor (I think it was C5) that had a lifted/broken trace. The factory had done the same thing and stuck it through the reverse side and soldered it that way. I'm on my phone now but will post a pic when I get to my computer. I was shocked when I saw it because the other ones I saw online were clean.

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Post by rocklander »

I've never felt so loved.. aww shucks..thanks all y'all... as you were..
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Post by quaternotetriplet »

is this a CE2 clone?

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Post by Scruffie »

quaternotetriplet wrote:is this a CE2 clone?
One too many ICs and trimmers to be a one to one. The Biyang is though.

No clue what the BBDs is here either, can't tell from the photo if it's 3007 or 3207.

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Post by Seiche »

rocklander wrote:I want to post in this thread so that Dirk will thank me too.
omg you get thank yous for every little shit you say around here. i try too hard. :scratch: :blackeye :thumbsup

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Post by HerrDoktor »

Hi,
in the past days I received this pedal.
It seems more bright and it's my first chorus pedal, so I don't know, if is an issue or normal.
Today I've opened the pedal and this is a pic:

Image

I thought it was a clone of BOSS CE-2 like wrote in this forum, but it seems different.
Some of you have the schematic?

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