Busking theremin

Posted: 3/6/2008 7:48:04 AM
fintushel

From: Santa Rosa, California USA

Joined: 7/25/2005

Yes, the jump start battery is rechargeable. I've had mine for about two years now, and it's still fine. You can get one from Walmart(!) or from a car parts shop. Mine is a Black & Decker "Start It" jump starter. People buy them to carry around in their cars for an emergency start--but it also supplies 12v steady DC current. I cut the jumper cables off it just for portability. An inverter plugs right in. I plug a gang plug or a power strip into the inverter and run my amp and theremin and looper off it with juice to spare.
Posted: 3/6/2008 4:49:57 PM
carport888

From: Redmond, WA

Joined: 9/1/2007

Cool! I'm DEFINATELY gonna have to try that! Thanks!
Posted: 3/7/2008 12:02:27 AM
carport888

From: Redmond, WA

Joined: 9/1/2007

I just got my Black & Decker "Start It" and power invertor, but now I have to wait 40 hours for the thing to charge for the first time! It'll be SO worth it, though! It will be done charging around 1pm on Saturday, just in time for a quick run to the park...if it's nice enough out.
Posted: 4/24/2008 11:19:10 AM
Xavier

From: Paris

Joined: 4/24/2008

Thierry, I'm in France too (Paris) . How do we make theremin B3 work on european 230 V ?
Posted: 4/24/2008 12:15:36 PM
Thierry

From: Colmar, France

Joined: 12/31/2007

There is a problem on the B3, the power cord from the power supply to the theremin is fixed in the housing, there is no plug on this side. So you would have to open the box, unsolder the "old" cable and solder the cable from the new external transformer, taking care of the polarity.

If you see a problem with this, I could do it for you. In this case, don't hesitate to contact me: frenkel.thierry(at)orange.fr

The price of the new (230 V) power supply is about 10 EUR.

If you want, we may also install a plug in the housing. This would allow working either on the power supply or on batteries.
Posted: 4/24/2008 12:25:56 PM
Xavier

From: Paris

Joined: 4/24/2008

Great ! I think I'll ask you to do it for me. What's your price ? I mail you.
Xavier
Posted: 4/24/2008 1:09:35 PM
Thierry

From: Colmar, France

Joined: 12/31/2007

... and I already replied!
Posted: 4/25/2008 10:08:03 PM
jegenes

From: New Zealand

Joined: 4/25/2008

Can you give my any info about converting my B3 to 240 volts? I'm in New Zealand now and need to get a new wall wart power supply for it, but it doesn't list the input voltage, or whether it's AC or DC. I'm assuming it's DC, but I don't want to fry it by plugging something into it. Thanks a lot.

john
Posted: 5/7/2008 11:44:07 AM
schielenkrahe

From: Morrisville, PA

Joined: 10/19/2005

Two quick things:

The standard Etherwave manual used to include the instructions for running your theremin off a battery in the Hotrodding section. If that's not the case, I'd be happy to send them to you. However, the instructions for the modification were written 10 years ago, for the standard. The innards of the theremin have changed a bit, but if you know anything about electronics (unlike me who still knows very little) you might be able to make the change.

I finally was able to begin street performing when I purchased the Kees Enkelaar theremin from Australia -- he gives you the choice of having it built for use with a wall outlet or running on a single 9-volt battery. I chose the battery, and I get about two hours of playing off a rechargeable.

Unfortunately, as last look, Kees was temporarily suspending production on his theremins. But keep an eye on his site - he has said he'll be building more. The only question is when.

Posted: 5/7/2008 12:32:22 PM
Thierry

From: Colmar, France

Joined: 12/31/2007

@jegenes:

The B3 operates theoretically from 14 to 30V DC.

Using a non stabilized 12V/200mA DC power supply (which has normally a off-load voltage > 14V) will be enough since the B3's power consumption is very low.

The black wire with the white stripe is the positive (+) lead.

Don't hesitate to ask me for more details if you need them.

I didn't want to fumble around with the wires, so I bought the fitting outlet for my new power supply, opened the B3 and built the outlet in the place of the hole where the power cable came out. This gives more flexibility. I took some pictures (low res with my portable phone...) of the action.

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