Taperssection.com

Gear / Technical Help => Ask The Tapers => Topic started by: foolsfortune on July 20, 2004, 12:11:35 PM

Title: Battery Box....again!
Post by: foolsfortune on July 20, 2004, 12:11:35 PM
So I followed the plans to build a battery box as best I could and it seems to work fine, but I was wondering.....should I be able to measure 9 volts at either jack?

I have the mics plugged in one jack and then a stereo 1/8" cable going from the battery box to my JB3.  When I put the multi-meter on the tip going into the JB3, I get like 8.59 volts or so.  I just don't wnt to jam voltage in there if I'm not supposed to.

I need to use this rig to tape my vocal lesson tonight, so if someone could email me at foolsfortune@hotmail.com, I'd really appreciate it.

Thanks
Mike
Title: Re: Battery Box....again!
Post by: peeeper on July 20, 2004, 12:16:44 PM
That's probably correct reading.  When the device is under load, whether is a passive or non-passive device, you will see a drop in voltage.  Most electronic devices have some amount of voltage drop when current is applied to the device.
Title: Re: Battery Box....again!
Post by: foolsfortune on July 20, 2004, 12:24:29 PM
Oh I'm cool with the voltage drop....no problem there, I was just wondering if I should be seeing voltage at both jacks.  Is it correct to have voltage going into the JB3 line in jack?

Also, do factory battery boxes have on/off switches?  When I clip the battery on and screw the box closed, the circuit will constantly be getting voltage.

Mike
Title: Re: Battery Box....again!
Post by: Sean Gallemore on July 20, 2004, 04:58:26 PM
Oh I'm cool with the voltage drop....no problem there, I was just wondering if I should be seeing voltage at both jacks.  Is it correct to have voltage going into the JB3 line in jack?

Also, do factory battery boxes have on/off switches?  When I clip the battery on and screw the box closed, the circuit will constantly be getting voltage.

Mike

yep, that's how the Sound Pro battery boxes work.

I can't answer the voltage question though
Title: Re: Battery Box....again!
Post by: mirth on July 20, 2004, 05:20:50 PM
This battery box I used to own from Reactive Sounds only closed the circuit when the mics were plugged into the jack.
Title: Re: Battery Box....again!
Post by: Karl on July 21, 2004, 03:38:26 PM
Contrary to some of the above posting, you should NOT be reading 9V at the end that plugs into your recorder.  If that's what happened, you need to recheck your wiring.  But, putting 9V into the JB3 end will not hurt it (you are just not going to get any mic signal through).

Don't worry about an on/off switch, mirth is right, you will not use any battery juice until you have a pair of mics plugged into the batt box.
Title: Re: Battery Box....again!
Post by: foolsfortune on July 21, 2004, 11:38:02 PM
Good to know Karl.  I didn't think I should 9V at the JB3.  It does record but teh signal is not very hot at all.  Does someone have a better wiring diagram than what's on the diy mic page?

I've got two sets of jacks that I can choose from (5 terminal or 3 - currently have the 5 pin ones installed), 2 capacitors, 2 100kOhm resistors, and battery terminal.

Should I see any voltage at the JB3 side? If so, how much?

Thanks
Mike
Title: Re: Battery Box....again!
Post by: foolsfortune on July 23, 2004, 12:03:05 PM
Anyone?

Maybe someone could pop their bbox cover off and check the voltage for me.
Title: Re: Battery Box....again!
Post by: Karl on July 23, 2004, 07:24:10 PM
You should see no voltage at the end where it plugs into your recorder.

Title: Re: Battery Box....again!
Post by: Sean Gallemore on July 23, 2004, 07:27:31 PM
archive!!
Title: Re: Battery Box....again!
Post by: foolsfortune on July 25, 2004, 12:19:42 AM
Hmmmmm.....that looks about like my batterybox, but I've got two 1/8" jacks with 5 pins (of which I've used 3 on each) and would like to see a rel simple hook-up diagram with this type of set-up. I'm still reading 8.5 or more volts at the JB3.

More pics, ideas, reports of the guts of your batterybox????

Bring it on.

Mike
Title: Re: Battery Box....again!
Post by: Karl on July 25, 2004, 01:34:34 AM
Well, then, you tell me--what's different about that diagram than what you've got hooked up?  If you follow your connectors back from the jb3, the the leads should go straight to the capacitors and nothing else (except obviously for the ground lead which should go to ground).
Title: Re: Battery Box....again!
Post by: foolsfortune on July 26, 2004, 12:34:29 PM
I had a friend who is better with electronics than I am check my work out and he says I've got it exactly as the diagram shows.

I still see 9volts at the mic end and the signal that the recorder is picking up isn't that stong so something is amiss here....
Title: Re: Battery Box....again!
Post by: foolsfortune on July 28, 2004, 04:44:58 PM
bump
Title: Re: Battery Box....again!
Post by: Karl on August 02, 2004, 02:03:55 PM
Your changing your story, now you say you have 9V at the mic end (and that's how it should be).  One way or the other, that diagram is right on.

Let's suppose you do have it right--this is a battery box, not a preamp, so you will not get a terribly strong signal in the recorder.  Tell us, what mics are you using, what setting do you have on the jb3, what are you recording, and how strong is the final recording?  By the sound of your last post, everything is working the way it should.