Is this a capacitor?

[Spork Schivago]

Hello everyone. I have a Ibanez Distoration pedal that I'm working on for someone. When the battery's plugged in, it works. When it's running off a transformer, it doesn't. I've checked the jack and it works and everything. Things that should read ground read hot with the transformer but not with the battery. Almost everything reads hot with the transformer hooked up. I'm testing components and wanted to know if this was a capacitor. I've never seen anything like it before. If so, can I test it with my ESR meter and is it polarized or non-polarized? The black dot is from a marker so I have an idea of how it goes back in... Thanks.

[rievax_60]

Re: Is this a capacitor?

yes, its some type of plastic film capacitor. 0.022uf or 22nf.
The J indicates its value tolerance, 5% I think.

[budm]

Re: Is this a capacitor?

Pedal effect boxes use outside of the barrel plug as positive, the inner is negative.

[Spork Schivago]

Re: Is this a capacitor?

Pedal effect boxes use outside of the barrel plug as positive, the inner is negative.

Thank you BudM. Do you or anyone else have any idea where I should start looking? I know that it uses a negative-pin transformer. I used a 9v battery and cut a broken transformer cord off and hooked it up to test because I do believe the original transformer is bad for this. I'm scratching my head on this one. There's a three pin connector going to another board. Pin 3 on the schematic shows it shoulkd be VCC, pin 2 GND and pin 1 should be D15. All three read hot with a transformer hooked in, including my 9v battery with a DC jack hookup.

[Spork Schivago]

Re: Is this a capacitor?

yes, its some type of plastic film capacitor. 0.022uf or 22nf.
The J indicates its value tolerance, 5% I think.

Thank you rievax_60. My ESR meter won't test them. I have to use my DMM. Are they polarized? Not 100% sure which way the first one came out.

[budm]

Re: Is this a capacitor?

You have the SCH? By the way, that polyester cap will not read right with ESR meter. I doubt that it is bad and causing the problem.

[Spork Schivago]

Re: Is this a capacitor?

You have the SCH? By the way, that polyester cap will not read right with ESR meter. I doubt that it is bad and causing the problem.

Yup, uploading it now. Thank you.

[Spork Schivago]

Re: Is this a capacitor?

Hey, R69 on the FUNCTION SW PCB 1/2 shows it should be 1Mohm. I haven't removed it to test it because it's surface mount and I have trouble with those but in circuit, it tests extremely low with my DMM. If I remember correctly, 200ohm. It's by the button that turns it on. Could that be the problem?

[budm]

Re: Is this a capacitor?

Does the wall wart read 9VDC when you plug it into the jack? I ran into some effect that just refuse to work when the DC input is less than 8.5V. What you can do is the use 9V battery to simulate the wallwart and feed it into the DC jack.

[budm]

Re: Is this a capacitor?

That section is just the Flip-Flop for toggling in and out effect.

[Spork Schivago]

Re: Is this a capacitor?

Does the wall wart read 9VDC when you plug it into the jack? I ran into some effect that just refuse to work when the DC input is less than 8.5V. What you can do is the use 9V battery to simulate the wallwart and feed it into the DC jack.

Never heard of the word wall wart. I'm assuming you mean the wall transformer? It does read 9VDC but the amperage jumps all over the place. Hench the reason I'm using the 9V battery to simulate the transformer.

[budm]

Re: Is this a capacitor?

So when you have 9V external connected to the DC input jack, it works, right? That wall wart (or external DC power supply) should be able to handle the current draw if you get the one with the correct capacity, it should not be jumping around if it can handle the power requirement by the effect box. What is the rating of this DC power supply you are using? If the wall wart is 9V when you measure without the load it should read about 14VDC.

http://en.wikipedia.org/wiki/AC_adapter

[Spork Schivago]

Re: Is this a capacitor?

I also pulled the diode on the main board and tested that. It tested good. There's some transistors that I tested but I don't know how to tell if they're bad. They say C1815 (but the schematics say 2SC1815). I tested five of them and all the readings from my DCA meter where the same except for something called Current Gain Hfe which read 315 on TR9, 284 on TR8, 284 on TR5, 295 on TR1, and 293 on TR2. Does that seem right?

[budm]

Re: Is this a capacitor?

If it works correctly with battery, then it is not the circuit problem, when you insert the plug into the DC jack, all it does is to switch the power from internal battery to the external power source, that is, nothing else change in the circuit. The Diode D7 connected to the DC jack is for wrong polarity protection.

[Spork Schivago]

Re: Is this a capacitor?

So when you have 9V external connected to the DC input jack, it works, right? That wall wart (or external DC power supply) should be able to handle the current draw if you get the one with the correct capacity, it should not be jumping around if it can handle the power requirement by the effect box. What is the rating of this DC power supply you are using?

No, it only works with a 9V battery hooked up to the battery connection. When I have it hooked up threw the DC jack, the unit does not work.

The DC power supply that I was using was 9VDC 0.5A (500mA), which, according to the internet, should work with this unit. It says to use one of three of their transformers and never use any others. This is a generic one the guy found. It can use a 200mA, 300mA or a 500mA 9VDC power supply.

I think they just put the only use theirs because of the negative-pin power supply.

[budm]

Re: Is this a capacitor?

So when you use the external power supply, what DC voltage do you get across the two pin of D7, Red probe on Cathode, Black on Anode.It should show 9V when you use the internal battery and the same reading when you use the external power. D7 is connected in parallel with the power source, either the internal battery or external power source. picture of your power supply?

[Spork Schivago]

Re: Is this a capacitor?

So when you use the external power supply, what DC voltage do you get across the two pin of D7, Red probe on Cathode, Black on Anode.It should show 9V when you use the internal battery and the same reading when you use the external power. D7 is connected in parallel with the power source, either the internal battery or external power source. picture of your power supply?

The DC voltage when using the internal battery is 8.36VDC, with my battery-to-DC-jack contraption, I get 0VDC.
The way I was testing it earlier when I got voltages across everything, I had to put the black probe on the negative part of my contraptions battery. Otherwise, I would never get a reading for some reason.

I messed up, didn't I? The problem has to be before that diode, right? And that diode is early in the circuitry, right? Could I try replacing that D7 1N4003 diode with a 1N4004 diode? Or do I have to use the exact same diode that's on the board?

Thanks.

[Spork Schivago]

Re: Is this a capacitor?

Oh, when you say power supply, what do you mean? The circuitry, wall wart or my contraption?

[budm]

Re: Is this a capacitor?

As you can see from the SCH, when you do not have the external power supply connected to DC jack J4, the Positive of battery A1 is connected to J4 pin 2 and through the switch contact of J4 pin 3, then out put to the Cathode of D7 which supply the Positive voltage to the circuit. The Negative of A battery is connected to J1 pin3, so when the Mono phone plug is inserted into the Input jack, the negative is then connected to J1 pin 1 which is connected to the circuit ground, thus complete the circuit path to supply the A1 battery to the circuit.
When the DC plug is inserted, J4 pin 2 and pin 3 circuit (switch) is open, which disconnect the positive of Battery A1 from the circuit, the positive voltage from the DC plug barrel is now supplying the positive to to the circuit through J4 pin3, the center pin negative of the DC plug is connected to J4 pin1 to circuit ground complete the path for the external power supply. The rest of the circuits does change, just the power supply source is changed.

[budm]

Re: Is this a capacitor?

Yes, the external power supply, or I call it wall wart. That D7 will conduct and crow bar (short the External power supply output) if the polarity is wrong. The Diode will destroy itself by shorting out and not letting the wrong polarity (clamp down the voltage to about 0.6v before it is damaged and shorted out), to get through to do the damage to the circuit. The unit will work without that Diode but you will not have protection. It sounds to me that your contraption does not have the correct polarity, that is why you are reading 0V on D7. IN4004 will fine for now.
So basically, the positive of either the internal battery or from the external power supply (wall wart, or what ever power source you are using to plug into the DC jack) will ALWAYS connected to the Cathode of the protection DIODE D7, the negative will ALWAYS be connected to the Anode of D7, D7 is in reverse bias mode so it will not conduct. I will conduct if the polarity of the battery or the external power supply is wrong.