Sunday, 29 December 2013
Friday, 22 November 2013
While audio was playing (with about 12 ohms across the input to ground) it was fine but there were very large pops when sounds started and stopped. I suspect (but I don't have a scope available to check) the module centres its signal on 1/2Vin but turns off the driver when it's not using it. That results in a big step signal when it turns its signal on and off, causing a pop.
Thanks to a tip from the AskElectronics subreddit, I now plan to build the headphone out circuit from the datasheet and then find some way to mix that with the existing headphone in, if possible.
Monday, 11 November 2013
I made this turned speaker for my girlfriend's birthday. It makes use of the boost converter described in my Instuctable. It was a bit of rushed build so I didn't have time to take pictures but here are the specs:
- 5V input to boost converter from a USB connection, boosted to ~18V.
- That 18V goes as input to a 10+W amplifier module.
- The amp drives a 3" full-range driver for 100-20,000Hz output.
- It's all housed in a purpleheart case that I turned on the lathe.
- After drilling holes for the accessory ports, I filled around them with Sugru for a nice finish. I also used Sugru to add some rubber feet.
Sunday, 15 September 2013
Monday, 8 April 2013
Monday, 11 February 2013
Wednesday, 30 January 2013
Sunday, 27 January 2013
Had a good time on the lathe yesterday. I turned this bowl from cherry. My first try at a decorative rim went quite well and I was pretty happy with the shape.
Unlike the previous two bowls that I attempted out of zebrawood, it neither smells bad (zebrawood smells like cheese), nor did it explode and go flying off the lathe!
Monday, 14 January 2013
Pair of random-strip chopping boards:
I was really proud of how these turned out. Here's what I did:
- Start with boards of different coloured wood. I used walnut, purpleheart and maple.
- Plane them all to the same thickness. Tip: run all the boards through the planer without changing its height, you won't be able to find the precise height a second time.
- Rip to random widths using the table saw. Start by ripping thin widths ff the side while the board is still wide; it's much easier than trying to split a thin strip into two.
- Spend plenty of time arranging the pieces for the best effect. I think I spent more than 30 minutes on this step and I feel like it paid off.
- Glue and clamp (I used Titebond III). Tip: the ten-minute working time of the glue passes very quickly; try a dry fit first and consider gluing the board up in two halves and then gluing them together. I wasn't quite quick enough on the bigger board and the first joint wasn't as tight as it should be.
- Plane the glued up board.
- Cross-cut on the table saw to trim the ends.
- Use round-over bit in the table router to round over the corners. Tips:
- If your boards are as thin as mine, use the fence rather than a bearing to set the round-over distance. If you don't, the bearing will be in empty space when you flip the boards over to do the second side.
- Do the endgrain first.
- Follow the piece with a scrap block to prevent tearout.
- Sand to desired grit.
- Finish with butchers block oil.
Christmas snowman ornament:
This is one of my favourite turnings. I finally got the hang of cutting beads and then finished him off with a pyro pen and a purpleheart hat.
A bowl and turned apple: