Stencil Success!

So I'd managed to knock up a pair of solder paste stencils, and now it's time for the moment of truth:  can I actually manage to lay down pastes and successfully solder some parts on?

Plastic Not-So Fantastic

In my last past, I made mention that I'd only intended to test the plastic stencil if the metal one failed.  Well, I got in-touch with my inner feminist and decided to start with the plastic stencil after all.  Why?  Well, the plastic sat flush with the boards, and I was thinking I'd probably not need the top frame in my Jig.

Sitting Pretty

Stencil Mania

Living in Australia....

...has a whole load of advantages, but one thing that sucks is that we are far from everyone else.  So once I've ordered my parts, I have to wait a while for the bits to arrive.  

And that usually gets me thinking.  Well, reading articles on the internet is kind of like thinking....

DAMN FINE DIY

There are some pretty talented and smart people out there, and I've recently read about some examples of DIY Solder Paste stencils.  Both of these guys have achieved some pretty impressive results, and with my upcoming projects, I started to think that the use of solder stencils might just save me some time.  

While I can hand solder SMD parts, and when set up I've been able to knock off over 100 parts an hour, it's bloody fatiguing.  Plus I have this hot air tool I picked up from eBay that I haven't tried yet either... so I began to hatch a plan.

However, rather than muck around with etching and all the drama that comes with using chemicals (e.g. negative WAF) I thought I'd give it a shot milling out a stencil at work.

Double or Nothing!

Double or Nothing!

As I talked about last time, in my last Seeed order I organised multiple designs in the one PCB service.  In this blog I want to let you know how I went from this:

Two for One

To This!

 Separated

Seeed-ing. And Not the Bit-torrent Kind.

IMPRESSIVE!

That's my opinion regards Seeed studio and their PCB Fusion service.

As I mentioned in a past post I've been working on a new project, and I've ordered the boards from Seeed. In fact, as I'm a tightarse (is it an just an Aussie thing?), I waited until I had a few projects to order.  You see, if you just order one $25 project, it costs you an extra $40 in shipping, but with Seeed you get *free* shipping for orders over $50 - and it's registered Air-mail shipping too.

So that's the first big plus.

Why We Test

The Magic of FETs

I've never had a lot to do with FETs before so I've been keen to experiment with and learn about FETs on my home projects.

As I wrote before in Basic Protection I like the simplicity of using a P-FET to provide reverse bias protection, and with my Alarm Interface I was planning on combining this reverse bias protection with current limiting.

As usual, I got it wrong the first time....

Cutting out the Middle Man

Home Alarm Monitoring

I have a home alarm system, and it's reliable and the monitoring company provides a good service.  For a bit less that a dollar a day, if the alarm goes off, they give me a call.  

Each and every time it goes off.  

My system has multiple zones, and my thinking is that if only the one zone is triggered, it's probably not a burglar in the house.  And I don't want my long weekend away spoiled by my wife continuously worrying about the single zone alarm that went off 2 hours ago and we are not going to be home for two more days.

I've requested with the monitoring company to *not* call me when it's only one zone, but policy is policy and they need to call.  Fair enough.

Basic Protection

BASIC PROTECTION

For a recent project I'm working on, I wanted to add some basic IO protection.  The requirements for this were:

• As usual, it had to be cheap
• It had to be bi-directional.  The pin to protect was configurable as either input or output.
• Provide short circuit protection
• Provide over-volt protection
• Provide reverse bias protection
• It also has to be cheap