Review of the Xantrex XPower PowerPack 400 Plus / Motomaster Eliminator 600 PowerBox

So I promised a review of this little bad boy, and here it is! Essentially the two products are the same, minus the labelling as Canadian Tire has a deal to rebrand a few Xantrex products including smaller and larger power packs.

In a nutshell, its main features are:

1. 12V, 20Ah sealed lead acid battery
2. 400W AC inverter (square wave)
3. Air compressor with short hose and fittings
4. Separate jumper cable for boosting low car batteries

On the road – aonomus rocks Virginia Beach

So I promised that I’d have something cool coming up, the major ’secret’ project I’ve been working on is an Autonomous Surface Vehicle entered into a AUVSI competition. While I will eventually do a full writeup with pictures and descriptions of various hacks that we have done, and the general construction of the boat, however I’m to tied up with actually helping the team with getting the project complete and working for the competition.

The competition itself is held at Virginia Beach, at the Founders Inn hotel under the Association for Unmanned Vehicles Systems International. Starting on July 19th onwards, each night at 10pm the officials have said that a ‘recap’ video will be posted. As well, at some point there will be a live webcast set up… more details as they come.

In other news, I have finally popped my ham radio cherry while on this road trip. My friend had his FT-897 set up in the roadtripmobile with a 2m magmount antenna ontop of the van, I managed to make my first contacts as a ham on repeaters on the way down towards VA beach. Since his radio and mine (FT-857) are fairly similar with the multifunction display driven controls, it wasn’t terribly hard to make contacts, unfortunately there were issues with the power wiring to the radio, so my apologies to anyone that was speaking with me and got cut off.

To tide y’all over, pics are available here: http://s139.photobucket.com/albums/q297/aonomus/ASV/

Project Updates

So I’ve been busy over the last few days on a few projects.

First, a quick and simple wood frame for 3x 1W solar panels I purchased for $9 a piece. I plan to add a shunt controller, or at the very least a simple LM317 regulator set for 13.7-13.8V, because the solar panels are happy putting out a unloaded 23V!.

Yet another quick and dirty project, during my post-exam cleanup I decided I wanted to build a stand for my printer to sit on so that I can store stuff (ie: paper) underneeth it. Just old spare MDF from Ikea furniture. Always a good hack for anyone with flat pack furniture that they can’t be bothered to sell.

Another project that is unfortunately a bit of a failure is a big rackmount power supply I built. Using a beefy transformer it supplies 13.8VDC regulated, at high current (20-40A). Unfortunately the transformer I used was a microwave oven transformer, re-wound for low voltage. The transformer contains a shunt, and the laminations are welded together, shorting them and creating a ton of wasted power, and high idle current. Testing with a proper meter, I found out that the idle current is 6A, with a power factor of 0.12! Once I replace the transformer, the power supply should be rock solid and reliable.

Enough of that rant, the technical details:
The power supply uses 42000uF in the smoothing filter, 2x ISOTOP/SOT-227 dual diode modules for rectification, and 4x 2n3055 pass transistors with a LM723 regulator. The inside is a bit of a rats nest, however it works well and even *with* the voltage sag due to the transformer being very lossy, I can push at least 20A within a range of 12-14V. Note that using fuses is a very good idea with a power supply that has a very large short current, and the fuse block is mounted behind the front panel (those 2 screws on the right).

Future additions include: more binding posts, and a volt/current meter setup, along with the replacement transformer.

Last but not least, new gear! I’m studying for my amateurs license, and I’ve already picked up my radio, and a cheap (as in free) tuner.