NeoVibe 12v 25ma lamp, is this the one from RS OK to use?

[albatross]

Hi

Wondering on whether this is the commonly used lamp used in the neovibe at radioshack, or can someone link me to the correct one?

This one looks a bit small?

http://www.radioshack.com/product/index.jsp?summary=summary&techSpecs=techSpecs&currentTab=techSpecs&cp=&custRatings=custRatings&features=features&accessories=accessories&productId=2102815&support=support&tab=summary

I'm sure smallbear dose not stock these as someone once stated.
Thanks!

[albatross]

Argh, radioshack do not ship to the fricken' UK!

Where else can I aquire something similar!!?? Surely RS cant be the only place on planet earth that stocks these.

Any form of help or pointers much appreciated!!

[marlin]

I'm using the 12v 20mA buld from Banzai, in my ears my Neovibe with that bulb sounds good. Banzai can have some crazy shipping times bult the bulb works fine! I used  a  500 ohm tim pot for the bias of the bulb.

[albatross]

Hi, thanks for the speedy reply I will order them from there soon!
I forgot about that place.

Thanks!

Also how are you powering yours? I plan on using a EH 24vDC 100ma wall transformer.

But im in doubt after looking at the file, theres a statement saying "DO NOT GROUND EITHER WIRE" but when you rig up the powerjack, negative voltage would be grounded using normal wiring methods???

So im assuming you wire this up with ground wires only connected to pcb & both jack sleeves, and have just both wires from wall transformer to jack + to point marked K, and - to J??

[Torchy]

You arent going to run this off batteries so the jack switching technique isnt  needed. Just run the ps wires from the dc jack to the pcb.
The drawing you showed part of already shows the input jack ground wire so extend this to the output jack, or use the pad below the ps ones (looks like O), or take it off the vol pot lug 1.

[R.G.]

But im in doubt after looking at the file, theres a statement saying "DO NOT GROUND EITHER WIRE" but when you rig up the powerjack, negative voltage would be grounded using normal wiring methods???

The original pedal is intended to be powered by an AC adapter. There is a four-diode rectifier bridge on the board - see that "DB1" on the picture? The real ground for the signal and for the box comes from the "-" side of that diode bridge. If you use a power jack that grounds either incoming wire to the chassis, the diode bridge shorts out the incoming power.

With DC, this is not as much of a problem. Ideally, you would follow the instructions - use a plastic body incoming power jack and do not let either the + or the - power wire touch ground. The diode bridge then makes sure that your DC polarity does not matter, as it automatically connects the + side to the circuit + and the - side to ground, through a diode.

Also how are you powering yours? I plan on using a EH 24vDC 100ma wall transformer.

That ought to be fine.

So im assuming you wire this up with ground wires only connected to pcb & both jack sleeves, and have just both wires from wall transformer to jack + to point marked K, and - to J??

Actually, you can connect + to either J or K and - to the other. The diode bridge makes it come out right.

[smallbearelec]

While I don't have them posted because they are easily accessible at RS to domestic customers, I keep a few RS lamps in a drawer to send to overseas users. E-mail me at smallbearelec@ix.netcom.com if you need one. NB: Manyu people here have indicated that they prefer the response of the 1.5v 25 ma. version.

Coming in on the next boat from China, docking here in mid-May: 1.5v 25 ma. lamps in both wire lead and E10 screw base. No more trips to RS for Neovibe builders...

Regards
SD

[albatross]

Hi
Thanks for the helpful replies, yes that all makes sense, I was tired at the time of writing and probably justifying the cost of the eh transformer + other things.

I didnt know the bridge rectifier acted as a converter for + and - and will make them come out the rightway regardless, but knew that it can convert ac to dc, if "convert" is the right word to explain, anyway ive never come across a project that uses one just yet.

Thanks for the offer, I will probably take you up on it, as I plan to socket the LDR's once up and running.