Millenium 2 problem

Started by fentom_lord, November 27, 2010, 05:39:10 PM

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fentom_lord

Hi everyone,
I just completed a Millenium 2 bypass circuit. I got the schematic here
http://www.geofex.com/Article_Folders/Millenium/The%20Next%20Millenium.pdf
I used a BS170 MOSFET and BC237's base-collector junction instead of a low leakage diode.
D1 is a 1N4148
R1 is 4.7k and R2 is 1k.

The problem is that the LED glows no matter if the effect is bypassed or not. What can be the cause?
Thanks in advance.

fentom_lord

Ok, I measured the voltages on this circuit (Oh, and the whole effect is powered with a 9V psu, btw)
The voltages are as follows:
LED anode: 2.26, cathode: 0.53

BS170: drain 0.53, gate 0, source 0
BC237: base 0, collector 0

Does that mean that the trannys are blown? Can this be the cause for its not working properly?

R.G.

Quote from: fentom_lord on November 27, 2010, 05:39:10 PM
Hi everyone,
I just completed a Millenium 2 bypass circuit. I got the schematic here
http://www.geofex.com/Article_Folders/Millenium/The%20Next%20Millenium.pdf
I used a BS170 MOSFET and BC237's base-collector junction instead of a low leakage diode.
D1 is a 1N4148
R1 is 4.7k and R2 is 1k.

The problem is that the LED glows no matter if the effect is bypassed or not. What can be the cause?
Thanks in advance.
This would happen if you had the MOSFET in backwards. Check the pin out for the BS170 from YOUR MANUFACTURER on the datasheet. Some of them are different from others.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

fentom_lord

Hey, R.G., thanks for the suggestion. I checked the datasheet and it turned out that I connected the BS170 correctly. Any other possibilities? Shall I replace the transistors with new ones?

R.G.

Quote from: fentom_lord on November 28, 2010, 06:50:01 AM
Hey, R.G., thanks for the suggestion. I checked the datasheet and it turned out that I connected the BS170 correctly. Any other possibilities? Shall I replace the transistors with new ones?
Maybe. Let's try a few things first.

1. Set up for testing. The Millenium circuit only needs power, ground, LED connected, and the control line to work. You can turn the LED on and off independent of the effect by connecting/disconnecting the control line to ground through a resistor. So leave the power, ground, and LED hooked up, and temporarily open the control line wire from your bypass switch. Tack-solder a 100K resistor on the end of that wire. If the Millenium is working, you can now touch the free end of that 100K to ground and it will turn the LED off. Remove the free end of the 100K from ground and the LED comes on. Does this work? If so, it was a miswiring at the bypass switch.

2. Pull out the bipolar. It's only there as a protection device. It's possible it was in backwards. Work now?
3. If no, OK, now try a new BS170.

R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

fentom_lord

Ok, I'll try to test the circuit tomorrow because I have to get a 100k resistor. I'm gonna buy the trannys anyway, just in case. I'll let you know as soon as I have the thingy checked.

R.G.

Quote from: fentom_lord on November 28, 2010, 05:53:11 PM
Ok, I'll try to test the circuit tomorrow because I have to get a 100k resistor. I'm gonna buy the trannys anyway, just in case. I'll let you know as soon as I have the thingy checked.
I just picked 100K out of the air. It will actually work with anything between a dead short and 1M.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

fentom_lord

Hey, R.G., I just tested the Millenium the way you suggested. It still works the same, the LED is constantly on. Gonna change the transistors and see if it works.

ca cat

I have done my own layout for millenium 2 plus
http://www.geofex.com/article_folders/mill2extn/mil2plus.htm - The least-fancy variant.

I dont know, how to connect it to dpdt... i connect the control ground to DPDT, 9v to + )V, ground to ground. Where do I connect the signal shunt line? FX input? Does the FX input go to DPDT?


Jamin' with JaM IT FX - www.jamitfx.com

R.G.

Quote from: ca cat on November 30, 2010, 07:39:55 AM
I have done my own layout for millenium 2 plus
http://www.geofex.com/article_folders/mill2extn/mil2plus.htm - The least-fancy variant.

I dont know, how to connect it to dpdt... i connect the control ground to DPDT, 9v to + )V, ground to ground. Where do I connect the signal shunt line? FX input? Does the FX input go to DPDT?
The circuit part of the Millenium is an INDICATOR circuit. It uses the otherwise-unused condition of one pole of a DPDT to turn an LED on and off. The wiring for all Millenium Bypass circuits is as shown for the Millenium I.

http://www.geofex.com/Article_Folders/Millenium/millen.htm


R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

ca cat

Quote from: R.G. on November 30, 2010, 11:22:23 AM
Quote from: ca cat on November 30, 2010, 07:39:55 AM
I have done my own layout for millenium 2 plus
http://www.geofex.com/article_folders/mill2extn/mil2plus.htm - The least-fancy variant.

I dont know, how to connect it to dpdt... i connect the control ground to DPDT, 9v to + )V, ground to ground. Where do I connect the signal shunt line? FX input? Does the FX input go to DPDT?
The circuit part of the Millenium is an INDICATOR circuit. It uses the otherwise-unused condition of one pole of a DPDT to turn an LED on and off. The wiring for all Millenium Bypass circuits is as shown for the Millenium I.

http://www.geofex.com/Article_Folders/Millenium/millen.htm




thank you for your answer!

But I still don't know where to connect the signal shunt line... Does the DPDT pole, dedicated to millenium bypass, control the shuntinng the fx input (turning it on/off)?
Jamin' with JaM IT FX - www.jamitfx.com

R.G.

Quote from: ca cat on November 30, 2010, 11:46:35 AM
But I still don't know where to connect the signal shunt line... Does the DPDT pole, dedicated to millenium bypass, control the shuntinng the fx input (turning it on/off)?
This brings up several answers, depending on what you're asking. I'm not sure what you mean by "signal shunt line".

1.  If you mean "the line that shunts the input of the FX circuit (not the Millenium Bypass circuit), then there is no good answer. There is no provision for shunting the FX circuit input to ground on the basic Millenium Bypass.

2. If what you mean by "signal shunt line" is the line which makes the Millenium bypass work, it connects to one of the throws of the DPDT as shown in the article I referenced.

3. If you are asking if the same wire that makes the Millenium circuit operate also acts to ground the input of the effect, no, it doesn't

4. If you are wanting to use a Millenium Bypass *and* get the input of your effect shunted to ground, you'll have to use one of the extended versions of the Millenium which do that. The basic circuit does not.

If you meant something else yet that I didn't pick up, post back here.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

ca cat

Looks like we didn't understand eachother.

I was talking about no. 4 - the extended version

I made my own layout fot the least fancy variant - http://www.geofex.com/article_folders/mill2extn/mil2plus.htm

and now I am wondering, where do I conect the signal shunt line. To the fx input?
Jamin' with JaM IT FX - www.jamitfx.com

R.G.

Quote from: ca cat on November 30, 2010, 04:47:45 PM
Looks like we didn't understand eachother.
I was talking about no. 4 - the extended version
I made my own layout fot the least fancy variant - http://www.geofex.com/article_folders/mill2extn/mil2plus.htm
and now I am wondering, where do I conect the signal shunt line. To the fx input?
That's the piece I was missing. Yes, to the FX input, or to any other place in the effect which disables sound.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

ca cat

Thank you!

Is in this case the fx input also connected to the DPDT switch (the pin, dedicated to fx input on the millenium bypass wiring diagram)?
Jamin' with JaM IT FX - www.jamitfx.com

fentom_lord

Hey, R.G., I finally replaced the transistors and everything works fine. I must have wrecked them somehow before. Now everything works great. Thanks for help.

R.G.

Quote from: fentom_lord on December 04, 2010, 01:32:22 PM
Hey, R.G., I finally replaced the transistors and everything works fine. I must have wrecked them somehow before. Now everything works great. Thanks for help.
Great!

The Millenium with the MOSFET is fragile in the same way as other MOSFET circuits; that is, the susceptibility of the MOSFET gate to static electricity. Sometimes they get zapped before they're protected in the circuit. That's what the resistor in series with the gate and the low leakage diode are for. They protect the MOSFET just in case. But they are not strictly needed for the circuit to work.

Good work!
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.