Fix a Biyang Tri Reverb- waste of time?

[seedlings]

Is it a total waste of time to try to fix this Biyang RV-10 Tri Reverb?  Symptoms: LED doesn't light and effect doesn't activate, only the clean signal passes as the footswitch is clicked and clicked.  It has done this a couple of times over the last month or so, and usually removing and reinserting power fixed it.  Same result on battery.  The footswitch itself is working properly.  Voltage is present at various places in the circuit, but without a schematic... with SMD resistors and caps... It's a little overwhelming.  I'm anxiously awaiting a reply from Biyang  .







CHAD

[seedlings]

Well, Lindy replied,

"Nice to see you in this email address and now please let me know the quantity of your defective pedals and please believe me I could do my utmost to help you, Generally, any schematic of our product are not allowed to give other customers, all this are the regulations in our company, So very sorry I couldn't give it for you, and you can tell me anything and later I can pass your word to my technician, Thank you!"

I gave her my word.

CHAD

[gritz]

It looks like Lindy's the same person who writes those emails telling me that someone has bequeathed me a bunch of money and I just have to send a little cash to get the paperwork done. :lol:

[PRR]

Bad jack, bad solder joint, or just too much stuff in too little space at too low a price.

You may be able to find/fix the first two problems with a bright light and a close-up eye.

[Mark Hammer]

Given the name of the pedal, the price, and the function, should we assume that this uses a trio of PT2399 chips  to produce reverb?

If so, most of the troubleshooting tips for the various PT2399-based circuits here will likely apply.  And there are plenty of them.

[seedlings]

Given the name of the pedal, the price, and the function, should we assume that this uses a trio of PT2399 chips  to produce reverb?

If so, most of the troubleshooting tips for the various PT2399-based circuits here will likely apply.  And there are plenty of them.

I need to get a magnifying glass and a better camera.  I couldn't read them.  Or, perhaps get one of the kids to look at it!

Biyang asked for a video of the trouble.  What- is there a language barrier or something?

CHAD

[Mark Hammer]

Biyang asked for a video of the trouble.  What- is there a language barrier or something?

CHAD

Yes.

[Quackzed]

-i'd check the traces under the dc jack, and in/out jacks, those pc mount jacks seem to break their traces alot... might be easy as reflowing the solder over a break...

[seedlings]

-i'd check the traces under the dc jack, and in/out jacks, those pc mount jacks seem to break their traces alot... might be easy as reflowing the solder over a break...

I thought that too, but the meter shows good voltage on various places throughout the circuit - in fact there is 5V across what (best I can tell) seems like where the LED is soldered in, but won't light.  I checked grounds from the input/output jacks back to the DC jack.  Checked continuity from input/output to the footswitch.  At lunch I'll try to read the ICs, then do some searching here.

CHAD

[seedlings]

I haven't messed with reverb or delay yet, but these ICs don't ring any bells.  Anyone?  All I know is U2 is known for delays 



CHAD

[Paul Marossy]

I agree, it's going to be pretty hard to fix it without a schematic.

[Mark Hammer]

I haven't messed with reverb or delay yet, but these ICs don't ring any bells.  Anyone?  All I know is U2 is known for delays 



CHAD

Grab a magnifying glass and tell us what the chips are.  Given Biyang's tyical pricepoint, I would be very surprised if these were NOT Princeton chips.

[seedlings]

IC9 is http://www.bdnc.com/datasheet/bd3201-14A_spec_V1.6.pdf

I can't find IC6 or IC7, but one of them has to be a clock.

CHAD

[Mark Hammer]

A-HA!!

It's the Wavefront chipset that Alesis used to use, and which forms the basis of the Femto-Verb project you can find out more about in the Digital sub-forum here.  The 3201 will provide 16 different effects, and Biyang has elected to use only 3 of them.

You want an incentive?  If you can repair it, there may be additional effects available to you for the cost of a couple of toggles.

[~arph]

Erm.. I can read them


IC9 has 3201 on it.. that is looks like a BBD number

IC6 and IC7 unknown.

IC2, IC1 and IC5 are all 4558 quad opamps.

So no, princeton..

EDIT: Sounds like a bypass problem by the way.. perhaps one of the other chips is a flipflop.. it could be just the switching that is bad.

[seedlings]

Erm.. I can read them


IC9 has 3201 on it.. that is looks like a BBD number

IC6 and IC7 unknown.

IC2, IC1 and IC5 are all 4558 quad opamps.

So no, princeton..

EDIT: Sounds like a bypass problem by the way.. perhaps one of the other chips is a flipflop.. it could be just the switching that is bad.

What kind of bypass problem?  The clean signal passes with the footswitch clicked or clicked (there is a faint loss of highs every other click).  The LED quit working.  These all happened simultaneously, and have happened before, but cycling power to the pedal cleared the trouble.  I checked each set of contacts for the footswitch, and the top 3 are shorted while the bottom three are open, and vice-versa with a click.

A-HA!!

It's the Wavefront chipset that Alesis used to use, and which forms the basis of the Femto-Verb project you can find out more about in the Digital sub-forum here.  The 3201 will provide 16 different effects, and Biyang has elected to use only 3 of them.

You want an incentive?  If you can repair it, there may be additional effects available to you for the cost of a couple of toggles.

I would LOVE to have rotary speaker option!!!!!

Also, it seems like the pins that connect the top daughter-board to the main board should 'pop apart' like they're seated in sockets (see the DC jack view picture)... but I've applied as aggressive of pressure as I care to, yet they don't budge.

CHAD

[Govmnt_Lacky]

IC7 

http://www.cirrus.com/en/pubs/proDatasheet/CS5340_F2.pdf

A/D Converter

[Paul Marossy]

Sounds like a bypass problem by the way.. perhaps one of the other chips is a flipflop.. it could be just the switching that is bad.

I thought that at first, but if it had the DOD bypassing scheme that uses an IC chip, why would a 3PDT switch be required? It would only need to be a SPST momentary switch in that case IIRC.

[seedlings]

IC7 

http://www.cirrus.com/en/pubs/proDatasheet/CS5340_F2.pdf

A/D Converter

Good eyes!  Thank you! <thumbs up>  Does this mean IC6 is the clock?

CHAD

[seedlings]

Sounds like a bypass problem by the way.. perhaps one of the other chips is a flipflop.. it could be just the switching that is bad.

I thought that at first, but if it had the DOD bypassing scheme that uses an IC chip, why would a 3PDT switch be required? It would only need to be a SPST momentary switch in that case IIRC.

It is supposed to be true bypass.

CHAD