Waveform generator Kit build

The Bitscope has a wave generator built in, but I felt that, as part of my soldering apprenticeship, I should build a kit that would add to the understanding of an oscilloscope, so I had ordered a five dollar XR2206 based waveform generator kit which arrived last week and we will travel through the gauntlet of welding it together. This is basically what you receive in one of these kits, components, main board, case and difficult to read instructions :

The components, along with an acrylic case to hold the item. What is not shown in the photo is the missing fifth non-polarised capacitor which I later found stuck up on of the knobs. Twenty-eight components and a case. There would be over seventy soldered joints to be done and I was surprised how my skills have improved over the last few kits.

In true Blue Peter fashion, here is one I made earlier:

I mean ok, some things were not perfectly aligned, but that is the nature of these fiddly little kits, they are large enough to be completed, yet small enough to be difficult and frustrating. However, a pat on my back for completing this with my sausage fingers and increasingly dodgy eyeballs.

The case almost made me lose it, perhaps I was approaching the end of my patience after soldering everything, but the case components needed to be stripped of their protective paper, and then the uncooperative puzzle needed to be assembled. It was indeed a wriggly little thing and some of my slightly off tolerance soldering of the bits came back to haunt me. 

The input was supposed to be 12V but to test I used a 5V supply, but that was enough to prove that the new gizmo worked. I tested later with the correct voltage and the output was definitely better. The kit was completed in about an hour and a half, it would heve been quicker if I had found the missing capacitor before I started, it would have been less frustrating if I had more accuracy in soldering a couple of the larger items, the power input and the potentiometers which had a direct effect on assembling the case, but it was done, and I was happy.

It has been a good week, the eureka moment with the Bitscope and the success in the waveform kit.

Bitscope BS10

The electronics journey is continuing and I worked out my multimeter needs, my bench power supply requirements and I decided to investigate oscilloscopes. I have to admit, I am mostly clueless about all of this, brain the size of a planet but it is becoming more and more unwilling to allow things to stick, sort of a low gravitational pull, things land in there and then bounce right off into space.

Multimeters, Bench power supplies, oscilloscopes. The amazon marketplace is an absolute quagmire full of questionable products, so for weeks I was looking at oscilloscopes, digital ones, and I was contemplating a used Tektonix TDS 1012 from eBay, sourced from a Vancouver university and probably fifteen or more years old, and on the other side of the coin, a new Chinese import on amazon, both of which would be setting me back around two hundred and fifty buckeroonies.

The Chinese unit by FNIRSI, named I assume by throwing a bunch of random scrabble tiles at a fast moving bucket full of poo, was a contender and as prime day arrived the price came down a little, but I have faith in my fate and I resisted. 

I was off at the swap and shop, talking to the retired electrician, and he mentioned a contact on used Victoria, so I logged onto the website and found him, and we had quite a good chat about oscilloscopes. The chat made my enlarged brain think more deeply and I was in doubt about the meaning of life, the origin of all things and the existence of toast. It seemed to me after the large thunking session, that an oscilloscope would take up a lot of real estate on my finite sized bench, and right there on my workspace was a keyboard and screen in the form of my laptop, so perhaps there was another solution?

It was a fortunate moment, for there on the auction site was a thing called a Bitscope, an external piece of hardware that would interface via USB into a computer and the software would create a DSO or Digital Storage Oscilloscope, in effect a solution for my needs and limited desktop space. In addition, the used unit would only end up costing me ninety dollars, a definite incentive for purchase and investigation.

It took a week of brain stretching before the eureka moment, but the understanding landed on the surface of my brain and I hope it will create a colony there. In the photo above you can see the size of the unit, hooked into my little laptop and recording two channels of signal from a simple hookup onto a little motor, with power from that cheap bench supply magnified an extreme number of times to show the ripple and the noise. The Bitscope is a capable device and instead of me throwing words at the screen to describe it, I think an annotated photo of the innards will explain far better than my extended mumblings.

It is indeed an amazing little device and the software works very well. I hope that my learning will continue and I can make good use of it in the coming years, also included was a BNC adapter, so I will be obtaining "real" oscilloscope probes from the far off lands, in fact, one is probably on a camel plodding over the Himalayas as I type.

One last thing, this unit also has a waveform generator built in, which is very important because when you have nothing to do you can connect it up and spend hours just staring at pretty little graphs on the screen and marvel how much more intelligent you are than a tree stump.