fixing a broken Pearl delay pedal - where to start?
- Pacafeliz
- PAT. # 2.972.923
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fixing a broken Pearl delay pedal - where to start?
well i bought this litte hottie "blind" - in "as is" shape (i should have known better...)
anyway, when i put the battery in and plug it in, the "battery check" light comes on, but then nothing more happens... no sound, no reaction from the on/off switch, etc.
nothing on the inside/board looks broken, tampered or burned...
is it only a paper weight now or how and where would i try to fix it?
thnx,
Pat.
i love delay SO much ...that i procrastinate all the time.
- rumfoord
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Re: fixing a broken Pearl delay pedal - where to start?
Worst case: such a beautiful beautiful paper weight
Business idea: 3d printed miniature pedalboards for use as paper weights
- Pacafeliz
- PAT. # 2.972.923
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Re: fixing a broken Pearl delay pedal - where to start?
yes i wanted one for -like- always. one of the coolest looking effects EVER!!!
i love delay SO much ...that i procrastinate all the time.
- ludobag1
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Re: fixing a broken Pearl delay pedal - where to start?
seriously it is not the easier thing to repair ,send it or bring it to a guy who know , lot of things in and i think some rarity chips du to age
if i have it on my Bench i can look at for wiring and more , but at first you need to search the shematics of this nice paper weight
if i have it on my Bench i can look at for wiring and more , but at first you need to search the shematics of this nice paper weight
- Pacafeliz
- PAT. # 2.972.923
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- Joined: Sun Jul 29, 2007 6:34 pm
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Re: fixing a broken Pearl delay pedal - where to start?
thanks! i have the schematic here now, but i don't understand any of these things...ludobag1 wrote: ↑Sun Aug 05, 2018 3:11 amseriously it is not the easier thing to repair ,send it or bring it to a guy who know , lot of things in and i think some rarity chips du to age
if i have it on my Bench i can look at for wiring and more , but at first you need to search the shematics of this nice paper weight
would you take a look at it?
i love delay SO much ...that i procrastinate all the time.
- fuzzjunkie
- Expat
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Re: fixing a broken Pearl delay pedal - where to start?
Some of those old analog delay chips are getting rare these days. Like Germanium transistors. It could be an expensive fix if one or more went bad, which is probably what happened.
- oid
- PAT. # 2.972.923
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Re: fixing a broken Pearl delay pedal - where to start?
Some of those chips have been reissued, since this is a better powered model, there is a fair chance you are in luck on the chip, the most common chips for battery units are available.
Since you get no sound at all that means the problem is with something common to both the delayed and undelayed signals, so the input or output circuitry, bypass switching or the power, the battery check light suggests power. Chances are either something has shorted to ground or the switching circuitry has failed, the i/o buffers tend to be robust. You could still have a dead delay chip as well.
If you got yourself a meter, post a link to the schematic and I will report back later tonight with some measurements to take.
Since you get no sound at all that means the problem is with something common to both the delayed and undelayed signals, so the input or output circuitry, bypass switching or the power, the battery check light suggests power. Chances are either something has shorted to ground or the switching circuitry has failed, the i/o buffers tend to be robust. You could still have a dead delay chip as well.
If you got yourself a meter, post a link to the schematic and I will report back later tonight with some measurements to take.
Logic gates based on billiard-ball computer designs have also been made to operate using live soldier crabs of the species Mictyris guinotae in place of the billiard balls.
- Pacafeliz
- PAT. # 2.972.923
- Posts: 18572
- Joined: Sun Jul 29, 2007 6:34 pm
- Location: Cococologne, Germany
Re: fixing a broken Pearl delay pedal - where to start?
thanks! i sent you a PMoid wrote: ↑Sun Aug 05, 2018 9:52 amSome of those chips have been reissued, since this is a better powered model, there is a fair chance you are in luck on the chip, the most common chips for battery units are available.
Since you get no sound at all that means the problem is with something common to both the delayed and undelayed signals, so the input or output circuitry, bypass switching or the power, the battery check light suggests power. Chances are either something has shorted to ground or the switching circuitry has failed, the i/o buffers tend to be robust. You could still have a dead delay chip as well.
If you got yourself a meter, post a link to the schematic and I will report back later tonight with some measurements to take.
i love delay SO much ...that i procrastinate all the time.
- ludobag1
- PAT. # 2.972.923
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Re: fixing a broken Pearl delay pedal - where to start?
no sound at all ,it is normally easyer to fix ,wire cut ect ……
the chips are foundable , but with the spaghetty in, need a schematics to look at closely and without the thing on the Bench it could be long to find the error
the chips are foundable , but with the spaghetty in, need a schematics to look at closely and without the thing on the Bench it could be long to find the error
- Unicorn Warrior
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Re: fixing a broken Pearl delay pedal - where to start?
Have you considered getting it checked out by analogman?
- oid
- PAT. # 2.972.923
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Re: fixing a broken Pearl delay pedal - where to start?
Shipping to and from Germany plus the repair bill seems like it would be a quite pricey solution? I would expect there is someone in an area the size of Cologne who does this stuff, if not there certainly somewhere in Germany.
After going over the schematic it does not look like it will be to hard to sort out anyways, likely this is just a power problem and something is sucking enough current to confuse the battery check light and starving the rest of the circuit from the power it needs to function, a cap failing to short is generally the culprit in such cases, so simple fix.
After going over the schematic it does not look like it will be to hard to sort out anyways, likely this is just a power problem and something is sucking enough current to confuse the battery check light and starving the rest of the circuit from the power it needs to function, a cap failing to short is generally the culprit in such cases, so simple fix.
Logic gates based on billiard-ball computer designs have also been made to operate using live soldier crabs of the species Mictyris guinotae in place of the billiard balls.
- Pacafeliz
- PAT. # 2.972.923
- Posts: 18572
- Joined: Sun Jul 29, 2007 6:34 pm
- Location: Cococologne, Germany
Re: fixing a broken Pearl delay pedal - where to start?
Thanks yeah, I'll be PMing back to you this afternoon. It's been crazy hot and busy here...oid wrote: ↑Tue Aug 07, 2018 7:35 pmShipping to and from Germany plus the repair bill seems like it would be a quite pricey solution? I would expect there is someone in an area the size of Cologne who does this stuff, if not there certainly somewhere in Germany.
After going over the schematic it does not look like it will be to hard to sort out anyways, likely this is just a power problem and something is sucking enough current to confuse the battery check light and starving the rest of the circuit from the power it needs to function, a cap failing to short is generally the culprit in such cases, so simple fix.
WE CAN DO THIS!!! (I hope...)
i love delay SO much ...that i procrastinate all the time.
- oid
- PAT. # 2.972.923
- Posts: 834
- Joined: Sat Feb 10, 2018 8:19 pm
Re: fixing a broken Pearl delay pedal - where to start?
We can, it may take some time due to the slowness of doing such things via the internet and our difference in time zone, but we can get there.
I have not gotten around to marking up the schematic yet, was a bit out of it due to illness the past couple days and actual thought was not happening. Need to see if I can find the right schematic as well, this one lacks the battery check circuit and could be different in other ways as well, it will likely work for our needs though, changes tend to be small between versions, may just be the battery check circuit is the only difference. If you can get a decent photo of both sides of the PCB that will help since I will be able to see what you see.
Logic gates based on billiard-ball computer designs have also been made to operate using live soldier crabs of the species Mictyris guinotae in place of the billiard balls.
- Pacafeliz
- PAT. # 2.972.923
- Posts: 18572
- Joined: Sun Jul 29, 2007 6:34 pm
- Location: Cococologne, Germany
Re: fixing a broken Pearl delay pedal - where to start?
Alright, coming up later today! THNX!
i love delay SO much ...that i procrastinate all the time.
- s_mcsleazy
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Re: fixing a broken Pearl delay pedal - where to start?
any gut shots of the thing? might be the easiest way to figure it out. the big hope with bbd pedals from this era is hoping the chips still work and the regulators aint died
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