Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => The Newcomer's Forum => Topic started by: mpuckett on May 25, 2009, 05:45:03 PM

Title: Looking for Ruby power circuit mod
Post by: mpuckett on May 25, 2009, 05:45:03 PM
Hi,
I have just built my first Ruby and it works and sounds great! I am most definitely a newbie though and while I can follow directions and solder ok I really have no idea how to do any kind of circuit design.

I am looking for a mod to the power supply for the ruby. I would like to provide both a battery and a line power supply and have the battery automatically disconnected if the line supply is plugged in. So it would run off the battery supply normally until the line cord is plugged in which would switch the battery off and run off the line instead.

Does anyone have a simple circuit diagram that can accomplish this?
Title: Re: Looking for Ruby power circuit mod
Post by: sergscar on May 26, 2009, 10:50:59 PM
Hi mpuckett,
When building my Ruby, I've considered to have both power options (9v battery + 9~12V DCIn) availables, in parallel. However,  I take the simple action of unpluggin' the battery when using the DCIn (or viceversa).

I'm also a newbie, therefore can't give you a complete response to satisfy "all" your questions, but I guess that, by using diodes in the "+" poles of the 2 power supplies, you could run the Ruby with both of them connected at the same time, since the diodes will just permit the current to flow only in one direction (in fact, that's the principle of the diodes)

In case you wish, I can post a picture of how I did on mine (without the diodes...).

Any expert advice out there ?
Title: Re: Looking for Ruby power circuit mod
Post by: phatt on May 27, 2009, 08:37:26 AM
Hi there mpukett,
There are several ways to do it.
This is similar to the way Boss pedals do it but you do need the right 6.5 input socket which turns the power on when you insert a jack plug. Just use a stereo TRS socket. (Tip-Ring-Sleve)
When you insert a mono plug the Ring is shorted to ground which turns the unit on.
So TWO Things are happening here,
Input socket turns the unit ON (by connecting the ground to the negitive rail) and inserting the wallwart disconnects the the battery positive passing supply over to the wallwart.

Be aware that the DC socket is a trick to wire up as it has 3 terminals. The centre is usually obvious but if you wire the other two wrong then you can fry your battery.
These Aux power sockets come in many sizes so make sure you use the same dia as the plugPak/Wallwart you use.
Diff dia's, diff lengths, I do wish they would try to stick to one type/size,,
it would make life just that little bit easier.

Use a plugpak that is well regulated and designed for audio use,, some are porely regulated and can add a lot of unwanted noise to your sound.
I've drawn the aux power as "Centre Negative" (Boss) but there are other ways to do it.
Hope it helps a bit. Phil.
Title: Re: Looking for Ruby power circuit mod
Post by: mpuckett on May 27, 2009, 01:12:10 PM
Hi Phatt,
Thanks very much for the diagram. I think I can follow that. Could you tell me though why the input needs to be a stereo jack plug? Does it function the same as a jack plug that contains a normally open or a normally closed switch? The current jack I have is just a mono tip, ring. On a tip, ring, sleeve jack would that be a left, right, ground connection?
Title: Re: Looking for Ruby power circuit mod
Post by: phatt on May 28, 2009, 11:03:46 AM
Quote from: mpuckett on May 27, 2009, 01:12:10 PM
Hi Phatt,
Thanks very much for the diagram. I think I can follow that. Could you tell me though why the input needs to be a stereo jack plug? Does it function the same as a jack plug that contains a normally open or a normally closed switch? The current jack I have is just a mono tip, ring. On a tip, ring, sleeve jack would that be a left, right, ground connection?

Yes your right it *IS* a stereo socket but who said you have to use it for audio?

As your only needing *Mono Audio* then the Ring is left *Unused*. So now we can be inventive here and use the ring as a Switch.     Pretty kool ay?
There are lots of oddball tricks like this used in electronics.
Understanding analog switching takes time to grasp sometimes it can bend the brain even for those who are experienced.

Yes you can use a simple mono socket but you then need another seperate power switch so why not use the insertion of a mono guitar cord to bridge the *unused ring* to the battery negative ,,switching on the unit as you plug in.
Phil.
Title: Re: Looking for Ruby power circuit mod
Post by: mpuckett on May 28, 2009, 03:26:47 PM
Phil,
Thanks very much! This design looks just perfect for what I want to do. After studying it more carefully I now appreciate just how clever it really is. Pretty kool indeed!

Now to find the right Aux socket...

Thanks again,

-mikep