Millennium Bypass questions?

[peps1]

Wanted to add some indicator LEDs to some old projects and thought rather then forking out the cash for a load of 3PDT foot switches I would try Millennium Bypass
.
Trouble is there seems to be Millennium Bypass "Rat, 1, 2, 3 , C" and so on, so what the most upto date variant?

I also see the recurring theme of Low leakage diodes........what are some common Low leakage diodes?   

[ppaappoo]

You have two Principal types, Millennium Bypass 2 & 1 Plus

In this Brazilian forum http://www.handmades.com.br are a great PDF http://www.handmades.com.br/images/stories/projetos/Millenium2FET/millenium.pdf

If you use a bf245 for the millennium 1 just invert it.

[R.G.]

Trouble is there seems to be Millennium Bypass "Rat, 1, 2, 3 , C" and so on, so what the most upto date variant?

Millenium 1 - uses JFETs, can be can cantankerous because of the variations of JFETs.
Millenium 2 - uses MOSFETs, much faster/snappier switching
Millenium C - uses CMOS logic chip, which costs about the same as a MOSFET transistor, but has more legs. Much more flexible, but bigger.
Use the Mill 2 or C. It's less variable.

I also see the recurring theme of Low leakage diodes........what are some common Low leakage diodes?   

The important part is the **high** leakage diode. You have to get that right for it to work at all. Most signal diodes such as the 1N4148 and 1N914 qualify as high leakage diodes.

The low leakage diode is a protection part for MOS (and CMOS) switches, and can be left out if you're willing to troubleshoot it in case it ever fails. The easiest low leakage diode is to take any ordinary NPN silicon transistor in a TO-92 package and clip the emitter lead off. The remaining base-collector diode is a low leakage diode. It is possible to find low leakage diodes in diode packages, but it's a PITA and they're harder to find, because almost all low-current signal diodes are optimized for switching quickly, and that's the same thing that makes them higher leakage. Use the B-C junction of an NPN transistor by clipping off the emitter lead at the body.

[peps1]

Thanks guys, so If I wanted to go with the 'Millenium 2' I just need a pair of 1n4148, BS170 Mosfet, LED and appropret resister 

Sincerely thank you for braking all that down for me!

[peps1]

MMMMMmmmmmmm......

having no luck using the following set up

(using a BS170) but seem to have voltage going to the led regardless of the switching, but a grounding issues as its not lighting up?

any suggestions?   

[Barcode80]

2 things:

1) are you testing it in circuit? The output of the effect circuit actually acts as part of the millenium circuit.
2) try replacing the diode on the right next to the mosfet with the B-C NPN transistor junction as mentioned. As he said, the LOW leakage diode is the crucial piece, and a 1N4148 is a high leakage diode.

[peps1]

Yep testing in circuit (a big muff, so nothing freaky or positive ground).

will try with a B-C junction first thing in the AM, and report back.

thanks for the Help! 

[ppaappoo]

The led never turn off completely o the by pass mod?

Try a 10k trimpot instent resistor.

[peps1]

No wont light up at all!

Gave it a go with the B-C NPN transistor and trimpot......bugger all  

(just to double check, im using a BS170, and this has DGS, rather then a SGD pinout of the 2n7000?)

[Toney]

 Yeah usually but I think I have read not always, best to check the datasheet of the actual manufacturer and remember those are quite static sensitive so they need care when handling.
If you have some CD4049 and enough room, the Millennium C seems like a really reliable solution to me. You can use it for positive or negative ground. Works really well.
http://www.aronnelson.com/gallery/main.php/v/Toneys-Album/Millenium+C-++CD4049+Negative+Ground+V2.PNG.html

[ppaappoo]

i use the fet version and works fine

[tubelectron]

Hi,

I agree with ppaappoo : the FET version works fine, even if I used the MBP only one time, and on a tube overdrive pedal, as below (PSU section) :



A+!

[ppaappoo]

yes, i recommend to you make it on the proto-board to select the correct value for the 1k resistor, for a 5mm led i use a smaller

[ppaappoo]

Hi,

I agree with ppaappoo : the FET version works fine, even if I used the MBP only one time, and on a tube overdrive pedal, as below (PSU section) :



A+!