Build Your Own Clone Message Board

I let a friend borrow my BYOC Phaser pedal. It was working fine when it left, and now it does not work. I am not sure what he did. He said he used an wall wart, I am assuming he used the wrong type. Can someone help, or is it a lost cause?

If it was an AC voltage power supply or a DC voltage power supply with the polarity reversed one or more of the op-amps might be toast. Check the reverse polarity protection diode (D1) to see if it is still good.

FYI, D1 is at the lower left side of the board, immediately adjacent to the battery lead connection eyelets.

Voodooman,

My pcb layout looks a lot different then the one you posted. I probably should have mentioned that this is an original BYOC phaser, not the phase royal. Here is a picture of mine. I am very new when it comes to building or troubleshooting pedals, so please forgive my ignorance. Hopefully with this picture, I can get a bit more guidance. Any information you can give me will be much appreciated. I am really starting to miss my phaser.

What are your symptoms exactly? Does the LED come on? Any sound in effect mode?

and perhaps more importantly, when Christ comes alive, will he play a gig with Frampton?

Ah, that's the original 1-knob version of the BYOC "Script 90" phaser.

I would still check the polarity protection diode first, as this may have blown if your friend plugged in a wall wart with center-positive polarity. You'll need a multimeter with a diode testing setting.

The polarity protection diode is the small orange glass component with the black stripe at the upper left corner of the PCB. Select the diode test setting on your multimeter and then touch the black probe to the lead at the end with the stripe and the red probe to the other lead. A good diode should measure about 0.7V.

Thanks everyone for your input. Currently, the Phaser is totally dead. The unit will not power on what-so-ever. Not with a wall wart, or battery. I am unsure what kind of wall wart my friend used. I was given a very nice multimeter by another friend of mine, a Fluke 76 DMM. The problem is, I have no idea how to use it. Again, i'm not too experienced with this sort of stuff. I cannot seem to find a manual for this thing either, which makes it even more difficult. I did a bit of searching online, and found a guide to test diodes with a DMM similar to the one I have. I followed their directions, and it seems the diode tests well, although I cannot say for sure, since I am unsure if I am even using the meter correctly. Any other information will be gladly appreciated. Thanks everyone for your time.


And yes, when Christ Comes Alive, Frampton will be there too.

Here's a tutorial on taking voltage readings: http://www.ladyada.net/learn/multimeter/voltage.html

You basically set the meter to DC voltage, clip the black lead to a ground point, like the middle lug of the input jack, and use the read lead to touch components and record that reading.

You should have around 9 volts on the "+9v" pcb pad near the bottom-left corner of the pcb. You should get the same reading on the stripped side of the small diode near the upper-left corner of the pcb. The non-stripped end of the diode should have zero volts.

While you're at it, you should get voltage readings from all the IC's too. Pin 7 on each chip should have the same voltage as the +9v pad, and pins 2,3, and 6 should have right about half that voltage. One of those chips, the oscillator (not quite sure which one since that's an old board), should have fluctuating voltages.

IC pinouts are orientated like this:

Morgan,

When I measure the +9v pcb pad, I get 0VDC. Earlier when I checked the diodes, I had the multimeter set to mV DC, not V DC, so I think that was an error on my part. Anyone have any other ideas?

Check that diode again, but look for a setting on the multimeter with a symbol that looks something like this:



Black probe on the lead at the striped end, red probe on the lead at the other end.

When I set the multimeter to the setting depicted above, the multimeter beeps at me and reads anywhere between .1 and .3V. Not really close to .7V like it should be.

I'd replace that diode. You can get 1N914 diodes (or 1N4148's--same thing) at Radio Shack.

Voodooman,

Just checked Radio Shack's inventory, and they have them in stock at the one closest to me. I will pick some up tomorrow and give it a go. I'm really hoping this will solve the problem, or at least part of the way solved. I really really miss this unit. My pedal board looks so sad without it on there. Thanks again everyone for your input, it is greatly appreciated.

Ok guys. So I replaced the diode, and behold, the unit now powers on. It passes signal, but no phasing is occurring. Anyone have any ideas? Thanks!

Retune the trimpot and record those voltage readings I mentioned earlier.

Morgan,

I just checked the +9V pad and still get a reading of 0V DC. And when I test pin 7 on the IC, I also get a reading of 0V DC. Anyone have any ideas?

I think you may be taking the voltage reading wrong, because the unit will not power on or pass signal with no voltage on the input. Can you describe to us how you're taking the reading? Is the LED coming on?

Morgan,

You will probably laugh once you read this. But, again, I am very challenged when it comes to this thing. I didnt have the unit plugged in when I was taking measurements. So no wonder I was getting nothing. Now, when I check the +9V pad, I get a reading of about 9.35VDC. And when I check pin 7 of all ICs, I get anywhere from 9.26V to 9.36VDC. The interesting thing, is when I check pins 2, 3 and 6, I dont get half the 9V I should be getting. I get anywhere from 8.36 to 9.38V. Any ideas?

No sweat, that's why I asked. Did you reset the trim pot? Can you give me the min and max voltages on pin 3 at either end of the trim pot rotation?

I'm not sure I know what you mean by resetting the trim pot. When I first replaced the diode, the power came on and I tried the unit for the first time, I did play around with the trim pot, to see if that would effect any thing. It did not change anything. I was still getting signal, but no phasing. Now when I move the trim pot hard left, or hard right and test pin 3 on all ICs, I get anywhere between about 9 and 9.36VDC. Anyone have any ideas?

EDIT: Another interesting thing I just realized. After I just replaced the diode, and tried the unit, it finally powers on. But will NOT power off. The LED stays lit no matter if I turn the unit on or off. This keeps getting stranger and stranger....

The led symptom sounds like another short somewhere. Please post some pics of the solder side of the pcb and of the jacks, switch, wiring, and pot.

It seems like I had a bad solder joint on the diode I just installed. Cleaned the joint a bit and re soldered, now its no problem, the LED is fine. But about the no-phasing issue....very odd.

By resetting the trim pot, I just meant turning it while listening to the signal again like you would have done when first building the pedal.

Will you re-check those voltages on pin 3 at each end of the trim pot? Your readings don't really make sense. The trimmer controls the bias voltage for all of the IC's and you should be able to basically go from 0 - 9 volts with it on those pins. Also, the IC's shouldn't pass signal with 9 volts on both pin 7 and pin 3, so you shouldn't be getting any signal when the LED is lit.

There's also a possibility that you have another bad joint somewhere that sort of went bad when the wrong AC adapter was used, or when you started moving the pcb around. I recommend posting those other photos I mentioned earlier.

Morgan,

I am sure you are getting frustrated with me at this point. But I am really trying to make an effort here, thank you for your patience. When I first replaced the diode, I did reset the trim pot, but that did not effect the sound at all. There was still no phasing. The unit power on and would pass signal, but no phasing. So when I have the unit plugged in, and I test pin 7 on all ICs, I get a reading of about 9.36VDC.

So after another test, it seems on all pins on all ICs test properly with about half of the 9V. The oscillating IC, I believe, the one in the lower middle area of the board. I have attached pictures of the board, wiring, and pots. If anyone has any further advice, or information, I would appreciate it. Thanks!