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Help Pork Barrel 18v - Changed IC type

Started by memor82, October 30, 2017, 09:57:10 PM

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memor82

Hi everyone.
I connected a 18v plug into the Pork Barrell.
The pedal doesn't work for a minute or two.
After that i tried to connect the pedal to a 9v plug.
Now the pedal is working..but the sound is a little distorted.
Could I have damaged something?  :'(

Thanks

NFX

try a new bbd, if still distorted its time to investigate further
Newbury Effects

memor82

Quote from: NFX on October 30, 2017, 10:08:01 PM
try a new bbd, if still distorted its time to investigate further

So may I have damaged the MN3007?

Scruffie

Start with the 9V1 zener, that should have clamped the voltage down, protecting everything and they don't really like having to do that job. If replacing that doesn't fix it, then go on to any electrolytics rated under 18V.

The BBD and its clock likely escaped unscathed, the zener is there to clamp the voltage down in the event of over voltage and there's a series diode with the supply which will have dropped the voltage a few hundred mV and they have a terminal voltage of 18V+/-0.3V.
Works at Lectric-FX

memor82

Quote from: Scruffie on October 30, 2017, 10:26:28 PM
Start with the 9V1 zener, that should have clamped the voltage down, protecting everything and they don't really like having to do that job. If replacing that doesn't fix it, then go on to any electrolytics rated under 18V.

The BBD and its clock likely escaped unscathed, the zener is there to clamp the voltage down in the event of over voltage and there's a series diode with the supply which will have dropped the voltage a few hundred mV and they have a terminal voltage of 18V+/-0.3V.

The Zener is D4 (is the 2011 p.b. version).
I used MN3007, and don't have the zener.
From the manual:
"MN3007 version: Omit D4, and use a MN3101 for IC3"
http://www.madbeanpedals.com/projects/ARCHIVE/FilterMod/PorkBarrel.zip

I have MN3102 + MN3007

thanks

Scruffie

Ahh, it's the old version, that's less fortunate.

Right, well the MN3102 will have liked 18V a whole lot less than the 3007 (which still may well be okay) so you might need to replace that unless you have a scope to check its outputs but before that replace any electrolytics rated under 18V.
Works at Lectric-FX

memor82

Quote from: Scruffie on October 30, 2017, 10:38:49 PM
Ahh, it's the old version, that's less fortunate.

Right, well the MN3102 will have liked 18V a whole lot less than the 3007 (which still may well be okay) so you might need to replace that unless you have a scope to check its outputs but before that replace any electrolytics rated under 18V.

I think that the electrolytics are ok.
The smallest can handle 35v.
So could be the MN3102?
I do not have any of the two chips  >:( :(

Scruffie

Yup, replace the MN3102 and then if you still have a problem, it'll be the MN3007, everything else should be fine.
Works at Lectric-FX

memor82

Quote from: Scruffie on October 30, 2017, 10:51:07 PM
Yup, replace the MN3102 and then if you still have a problem, it'll be the MN3007, everything else should be fine.
Ok, thanks a lot man!
Time to order on musikding  ;D
byee

memor82

Quote from: Scruffie on October 30, 2017, 10:51:07 PM
Yup, replace the MN3102 and then if you still have a problem, it'll be the MN3007, everything else should be fine.

Hi Scruffie.
I've problem with my PB (first version).
I've changed both the Op.Amp. Now I've a MN3207 and a MN3102.I've allready changed the orientation of the jumpers.
I've also put the 8.2 zener diode for the MN3207.
Before I had MN3007 and a old MN3102. 8th pin of MN3102 lifted up and 4th and 5th pins of MN3007 linked together.
I've tried the same configuration with 3207, and doesn't works.
I've tried the "standard configuration" and nothing good..
the voltages:

4558:
1: 3.8
2: 3.8
3: 3.8
4: 0.0
5: 3.8
6: 3.8
7: 3.8
8: 9.2

MN3102:
1: 8.3
2: 3.9
3: 0
4: 3.8
5: 0.07 (varies)
6: 7.4 (varies)
7: 2.9 (varies)
8: 7.2

MN3207
1: 0
2: 3.8
3: 7.2
4: 7.2
5: 8.3
6: 3.8
7: 7.2
8: 7.2

TL062:
1: (varies)
2: 4.6
3: (varies)
4: 0
5: 4.6
6: 4.7
7: (varies)
8: 9.2

Thank you very much  :)

Scruffie

Your BBD bias voltage (pin 3) is very high, higher than the VB voltage it's effectively fed by, what voltage do you get with the 3207 out of circuit and where did you get it from?

Also the voltages on Q2 would be helpful.
Works at Lectric-FX

memor82

Quote from: Scruffie on December 10, 2017, 02:04:42 AM
Your BBD bias voltage (pin 3) is very high, higher than the VB voltage it's effectively fed by, what voltage do you get with the 3207 out of circuit and where did you get it from?

Also the voltages on Q2 would be helpful.
Ho Scruffie.
The voltage on pin3 without the op is 7.2 (same as with the op).
The voltages of the 2n5088 are:
C:9.2    B:3.8    E:4.9

I use a caline power (measured 9.2v out)

thanks!

Scruffie

I would check for a short between pins 3 & 4 of the BBD.
Works at Lectric-FX

memor82

#13
Quote from: Scruffie on December 10, 2017, 12:36:42 PM
I would check for a short between pins 3 & 4 of the BBD.

Yes! the multimeter said.. "beep"  :)
I tried to scratch between the two pins but nothing changed.
It could be the socket?!
Seems that there are shorts between pins 1 and 2 | 3 and 4|  5 and 6 | 7 and 8|  :o :o

Scruffie

Try the test again with power off and the BBD out of the socket.

Only pins 7 & 8 should be connected together.
Works at Lectric-FX