Basic PocketQube Power Supply

After posting a couple of pictures on Twitter of the small power supply I'd built for PocketQubes, I thought I'd give a bit more detail in a blog post.

Even though I'm building a different EPS (electrical power system) for my PocketQube "OzQube-1", I wanted a small power supply that could power the satellite while I am testing it.
I had a few requirements:

1. It needs to be able to be powered from a plug pack (wall wart) or from an external battery pack. 
2. It has to fit into the PocketQube PQ60 form factor
3. It needs to output 3.3V and 5V
4. It needs to have a similar current capacity to the real spacecraft EPS
5. Cheap

There is actually a very common thing that already fulfils most of these requirements - the humble breadboard power supply! The main issue is that they don't fit inside a PocketQube.

Fortunately, I have a prototyping solution that's already in the PQ60 PocketQube form factor - ProtoQube.

All that's needed now is a few components.

If you look at a breadboard power supply, they often have a DC jack, and a USB input. The problem with USB is that there's often a 500mA current limit. This wasn't going to work for me, so I opted for a 2 pin screw terminal input. 

Another issue with a breadboard power supply is the the voltage regulators. These are often SOT-223 surface mount parts. This is ok for a custom made power supply, but ProtoQube has a grid of holes, so a through hole regulator is needed. In order to keep the component count down, I went with fixed value voltage regulators. There are many on the market, so I went with some that were readily available - the ST Micro LD1117V50 and LD1117V33. These just need a single bypass capacitor on the input and output, and are capable of 800mA current.

Finishing off the power supply are some pin headers for each rail, and a LED indicator to show when power is connected. I also added a diode on the input for reverse polarity protection. Here's the schematic to show how it's all connected:

Assembling the power supply just requires some additional solid core wire, and the components arranged like you see in the pictures.

All that's needed now is to solder on the Hirose FX8C backplane connector, and some female pin header sockets so I can connect the power supply output to the rest of the stack!

OzQube-1 Presentation at Australian Cubesat Workshop

Late last year, the Australian Centre for Space Engineering Research (ACSER) announced that they were going to run a workshop titled "Launching Cubesats for and from Australia" in early 2015.

Yessss! Finally a smallsat event in Australia that I can attend, even if it is a 5 hour plane flight away.

After a suggestion from a Twitter follower ( Thanks @AusAndgie7 !) I made contact with the organisers to discuss the possibility of me doing a presentation about OzQube-1. As my email was sent between Christmas and New Years, the uni staff were on holidays and didn't reply straight away. But once they were back from their break, I got a reply saying that I was more than welcome to present! Now I just had to wait for further details as they arranged their schedules.

A few days ago, all the speakers received the draft schedule, and it looks like I'm on just before Tom from the PocketQube Shop, who is going to do his talk remotely via video conference. Each speaker in the "Missions" section has a  7.5 minute slot, including questions, so I'll have to make sure I don't spoil Tom's talk! Not to mention that this is the first time I've talked about OzQube-1 to a large audience, so hopefully I do ok. I don't want to have it turn into "7.5 minutes of terror"!

So if anyone that is interested in PocketQubes or Cubesats, and can make it to Sydney for April 1st, 2015, make sure you reserve a seat ( they're free). I'll be there all day, so come up and say "Hi!"

ProtoQube is here!!!

The PCB's have finally arrived! Get them from my Tindie Store:

New #PocketQube PQ60 Breakout board - "ProtoQube" #maker #amateurspace https://t.co/oVqnZbb0hS pic.twitter.com/WrqSc4Bb3q
— OzQube-1 (@OzQube1) December 20, 2014

PocketQube PQ60 Breakout and Prototyping board - ProtoQube!

I haven't added a blog post for a while, so I thought I'd put something out there on the PocketQube front.
I've posted various updates on the OzQube-1 Twitter and Facebook pages, but I'll try an put a bit more info around things here.

Apart from all the PCBs and subsystems I'm making for OzQube-1, I wanted to build something to promote the PocketQube PQ60 form factor, to show that it can be a versatile form factor, not only for satellites. The best way to do this is to make something that people can actually use.

So what better way than to create a breakout and prototyping board based on the PQ60 form factor!
I call it - "ProtoQube!"

The normal backplane connector for a PQ60 is a Hirose FX8C-60 (P or S, depending on whether it's the top or bottom connector). There's a few issues using it as an every-day board though:

• The pin pitch is .6mm , so it can be a bit tricky to attach wires to the connector pins.
• There are a choice of connector heights, so specifying one won't suit all purposes
• It's relatively expensive ( depending on supplier, but some are over $10 each in Australia)
• It has a limited number of insertion cycles

So I've broken out all the individual circuits to a 1.27mm ( 0.05") pitch connector along the edge of the board. The board can be used with or without a pin header. You could put some female sockets on the top of the board, just like an Arduino. 

In the middle is a regular 2.54mm (.1") pitch protoboard area. All the contacts are gold plated ( ENIG ....)

The board has footprints for both the top and bottom Hirose connector, and each circuit is passed through the board from bottom to top, so they could be used in a PQ60 stack

I'm going to be selling these for $25 through Tindie once they arrive, so send me a message or join the waitlist on Tindie if you're interested! They should be here by Christmas if I'm lucky.

Cool PocketQube Infographic!

The PocketQube Shop and the DIY Space Exploration website have teamed up to create this fantastic PocketQube infographic.

Courtesy of: DIY Space Exploration

67P Images from Rosatta

In case you've been living under a rock, the ESA spacecraft Rosetta is currently orbiting the comet 67P Churyumov-Gerasimenko.

In an attempt to involve the general public with the mission, ESA have published 4 separate Navcam images with anyone can use to combine together into a mosaic of the comet.

So here's my attempt from 4/9/2014:

Credit: ESA/Rosetta/NAVCAM/Stuart McAndrew

My Hackaday Prize Entry

Many of you out there already know of the website called Hackaday. They happen to be running a competition called "The Hackaday Prize", where people are invited to submit a project that meets a very lose criteria:

• You must actually build something
• It must transmit data to and/or from another device (computer, phone, duplicate/variation of your device, etc). This could be over the Internet, or using any other method of your choosing.
• Our main requirements have to do with documentation. This includes lists of parts, schematics, images, and videos. Remember, Openness is a Virtue.

So seeing as I'd just bought some of the NiceRF radio modules for testing, I thought I'd give the test board a name and enter it in the competition!

So the test board is called QubeCast Max.
(Pocket) Qube
(Broad) Cast
Max - because it's high power! And leaves room for other models in case I make more of them.

Please support PocketQube's and my entry!

http://hackaday.io/project/1726-QubeCast-Max

Give me a skull if you like the project!