Newton Power Plug dimensions.

[MidnightCommando]

Hey there guys.

I'm just wondering if anyone with physical access to a Newton MessagePad 2x00 or Newton eMate 300 and a pair of vernier calipers can help me here.

I need to know the barrel width (outer diameter of the power plug) and pin width (inner diameter of the power plug) for the DC input jack.

Any precise answers would be greatly appreciated as I'm currently hacking up a small Vreg that should make it safe to use most common wall-warts to charge a newton, and following that I will be making a complete DC supply unit, once I've got this prototype tweaked - let's face it, why buy a Newton Power Supply when you can make one in eMate Translucent Green?

 

[macgreg]

If you can wait until I get home next week I can check and measure all three (2100, 2000 and eMate) for you.

 

[MidnightCommando]

Thankyou kindly, I believe, however, that all three are identical. I merely need the measurements from one.

However, if you could confirm that the 100/110/120/130 takes the same size, that would be handy. If not, don't fret.

Once again, thanks!

 

[macgreg]

Just checked an OMP, a 120 and a 2100 and to the eye they are all the same size (barrel and pin).

I'm trying to get my hands on some vernier calipers to verify this...

Do you have any Newtons yourself? I'm very interested your voltage regulator should you get it working...

 

[MidnightCommando]

I have no Newtons as yet.

A forum member has promised me a bunch of eMates but ... well, let's just say that thus far the eMates have failed to materialise, so time will tell

There is no doubt in my mind that this voltage regulator will work. The theory is sound, the schematic correct. Once I've tested my (very pretty) PCB layout, I will be able to upload it as a small device that anyone with the technical inclination (and many without) can assemble themselves from readily-available parts.

The following idea is to use the voltage regulator module as the frontend to a custom DC supply that will be a drop-in replacement for the Newton 9W Power Adapter (providing 7.5V at 1.2A) - thankfully the charger itself is "dumb" and so not hard to reproduce functionally.

Of course, Jaycar has these nice project boxes in Bondi Blue that would probably look very nice sitting under an eMate's translucent green shell, but aesthetics are an issue for another day

The Voltage regulation device itself can be powered off any wall-wart that provides anywhere between 500mA and 1.2A at any voltage between 10V and 32V in its current form, though of course I'll make improvements with time.

 

[MidnightCommando]

OK!

I have the dimensions of the plug for the 3W adaptor (7.0V 0.5A ... this brings more questions.)

barrel diameter ø 4.8mm

pin diameter ø 1.5mm

barrel depth | 9.5mm

Apparently the 9W adaptor can be used to charge all Newtons... but its output is 7.5V 1.2A - the draw from an OMP is 7.0V 0.5A - half a volt could be enough to severely upset such machinery, can I get confirmation on this?

If the dimensions are the same I may have to add a switch and secondary resistor into the regulator circuit to switch between providing 7.0V (for OMP, 1x0 series) and 7.5V (for 2x00 and eMate) - unless of course it turns out that the 9W charger won't blow an OMP up, in which case my design is finalised.

Thanks again to macgreg for getting me an OMP to play around with and an original charger to test against.

 

[macgreg]

I can confirm that the Newton 9W Power Adapter H0165 (ADP-9AB) happily powers a Newton OMP.

 

[macgreg]

How did you end up going with this project?

 

[MidnightCommando]

Well enough that I have a working regulator board, schematics, and the math to support it.

I'll be publishing them soon, I'm still working on the optimal layout of the printed circuit board.

 

[macgreg]

Nice work - well done.