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After two weeks in the bottle, yes i know its still “green”, but what the hell, i have to taste it. I could see in the bottle this was going to be a cloudy beer, most other beers ive made have settled by two weeks and are almost clear, not sure what to put that down to.

Anyway, i poored two glasses, and i have to say, the head retention on this beer was the best of any beer ive made, so was the quality of the beer (ie no “homebrew” flavour to the beer), unfortunately, it was super hoppy, almost peeled the paint off the walls.

So, lesson learnt. Time to revise the recipe. I will note though, that this is going to have a very Coopers Pale Ale type flavour to it, probably down to the Pride of Ringwood hops, i dont mind, its a tasty beer.

After several years of making homebrew beer from a can of goo and a kilo of sugar, i have taken the next step to try and make a tastier (and hopefully not to much more expensive) beer.

I bought enough ingredients for two batches from thebrewshop:

• 4kg light dry malt extract
• 2kg dextrose
• 100g pride of ringwood hops
• 100g saaz hops
• 2pkts US05 yeast

As you can see, this was going to be a very basic extract beer. Single malt, with just two hop additions. The reason for this was i didn’t want to mess about with mixing different types of malt extract and too many hops because i wanted to see what a basic beer tasted like and use it as a benchmark for any beers after this one.

Recipe

• 2kg ldme
• 1kg dextrose
• 20g POR @ 60min (edit: 26g measured with scales)
• 25g Saaz @ 15min (edit: 23g measured with scales)
• US05 yeast

Beer is in fermenter at about 20 degrees (some may say too hot! but its the best i can do).

Original Gravity was around 1044

The beer has a really spicy smell, i think i may have added too much saaz. Will post once have bottled and tasted.

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Finally, after breathing in too many solder fumes, i have finished building these two kits. Not much to say, it was pretty easy. Here are a couple of photos

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Next thing is to buy the transformer, and set this thing up. Hopefully i don’t have to spend hours debugging!

The aim of this project was to build a simple, cheap guitar amplifier. I wanted to build an amp for around $200 without having to spend months designing it. Given these constraints i still wanted to build an amp that would shake the walls, oh and have atleast one or more tubes. Just for fun.

First was a trip to the local electronics store to see what i could get. Ended up coming out with a couple of kits and a heatsink.

Power Supply

The power supply is a simple kit from Jaycar – Power Supply Kit to suit SC-480. What i liked about this was that not only did it have +/- 40V rails for the power amp, it also has +/- 15V for powering a preamp. Perfect.

The only downside to this supply was the massive transformer it needs – 56V CT 134VA TRANSFORMER – 2.4A CENTRE TAPPED

Power Amp

The power amp i went for was the – SC-480 50W Amplifier

It just so hapened that the power supply was specifically designed for this amp. Bonus. The amp specs state that this is a 50W amp into 8ohms, but 70W into 4ohms which is how i will be running it, i think 70W is more than enough to shake the walls. I decided on a solid state power amp for ease of building and the fact that it was cheap.

The amp has low distortion and a good frequency range. Although all this means nothing to a guitar amp, so the desired sound will hopefully come from a well designed pre amp.

Again, the only downside i could see was that it needed a massive heatsink – Black Heatsink – DIECAST

Assembly

This is as far as i have come with the amp so far. Been thinking about cabinet and speaker design aswel as pre amp design. But for the time being i am assembling these two kits and researching the rest. More details will be posted soon.

The site  is no longer being hosted on godaddy, after reading about nearlyfreespeech.net and looking at their prices i decided to move the hosting to them. The site works by charging you only for the amount of storage and bandwidth you use.

The pricing structure is:

Plus $0.01 per megabyte-month (ie 1 cent per megabyte per month) for storage

So far so good, no problems. Would definitely recommend them!

I have recieved my board in the mail and after a few hours testing the code out i almost have it working as i would like. You can see the updated code below, hopefully it is cleaner, tried to tidy it up as much as possible. Also now use a pointer in the output (table) rather than testing the shape of the wave every time a sample is outputted, this should speed up the Timer_ISR quite a lot

Read more for code

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I am currently in the process of writing a synth for the Arduino development board. The project started as a school project on an 8051 development board but i soon figured out that this was way to slow. I am building the synth from an Arduino board and an 8bit R-2R DAC (plenty of circuits can be found at google).

The synth is based on the Direct Digital Synthesis method of producing waveforms digitally. I aim to get around 100Hz to ~4kHz operation out of it but im sure it is capable of frequencies up to around 50kHz. But this can be determined when the source has been verified and is working.

The source code for the Arduino has been written and attached below, but i have not verified it yet (my board is still in the mail). The DAC is intended to be connected to the Arduino board as follows:

Bit 0 (LSB) : Digital Pin 8

Bit 1 : Digital Pin 9

Bit 2 : Digital Pin 2

Bit 3 : Digital Pin 3

Bit 4 : Digital Pin 4

Bit 5 : Digital Pin 5

Bit 6 : Digital Pin 6

Bit 7 (MSB) : Digital Pin 7

I will provide more information and results when my board arrives

The source can be found by reading more

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This was a great movie, i’m not going to review it but I think you should watch these previews and go get the film, well worth the watch.