made a cake

Something like a Yorkshire tea loaf – about half a kilogram of fruit soaked over-night in tea, one egg, brown sugar, some bicarb, a bit of butter, plain flour, and some brandy that I randomly threw in ‘cos it’s Christmas.

And it turned out alright! Usually everything I make turns out flat, but this one wasn’t too bad. I suspect because it has a vast amount of fruit propping it up.

Apart from that, mostly I’ve been frenziedly drawing circuit boards to order from China to try and beat the UK customs changes come January 1st.

To explain a bit – at the moment there’s an arrangement called Low Value Consignment Relief, which means that any goods imported under the value of £15 don’t attract any VAT charges, which most of my PCB orders squeeze into.

Come January 1st, HMRC are binning this arrangement and have stated that the seller will be responsible for collecting the VAT, so that makes things less fun.

There were loads of things I was going to make (a Kobol clone with 3310s subbing in for the rare SSM2050s! an MS10! the DAC/gate output board for my imagined future MC-4 ripoff that I’ve been going on about for years) but mostly I’ve been churning out boring old clones of 100m boards. Yep, even the overly-complicated looking portamento module.

Other than that, the silliest is probably this board intended for my lovely Juno-6, which is basically a copy of the DCB interface in the Juno-60. Yeah! DCB!

At this point you’re understandably wondering why would anyone do this in this day and age, and I’d say, fair enough, it’s a bit daft.

Mostly it’s because I was too cheap to invest in a MIDI interface for this thing, but also because it’s more fun trying to work out how to get it going, even though it’ll be a bit more convoluted.

I’ve long missed the boat on buying an MSQ-700 for super-cheap, and OP-8/OP-8m are super-rare, so I guess I’ll end up writing a MIDI-to-DCB and CV/gate-to-DCB thing for an Arduino.

I’m sure it’d do-able to go from the Arduino to the Juno-6 direct, but I’m slightly nervy about knackering the MPU inside the Juno.

I opened the Juno up before I ordered the board just to see how much room I’ve got. Turns out I could easily fit some sandwiches and a banana in there as well as the board.

Loads of room. Probably not going to do the sandwich-box mod this time round.

Also there’s a suspiciously DCB-port-shaped hole covered by a plate at the back that will hopefully mean I can avoid any drilling, because you know that’s a bad idea. Potential Christmas fun to be had anyway.

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s950 screen replacement

Saturday afternoon, got a couple of hours, let’s change the screen in my S950.

Here’s the problem – backlight really dim in the late afternoon light. Even with the curtains drawn it’s hard to get a photo with the reflections. If anything this makes it look more readable than it was.

Dim looking screen on Akai S950

Let’s take it to bits.

Front panel removed from S950 to reveal buttons and original screen

I’m using the (slightly confusing) instructions from the Gearslutz Pimp my S950 thread. I bought a 40×2 display from buydisplay via Ebay – this is the one:

Stock photo of replacement display

The original screen has a 14-pin data/power connection on the left-hand side, and the backlight power connection on the right-hand side here:

Close-up of power connection on original screen

I was just interested to see what kind of voltage was appearing here, but it was hard to measure – didn’t seem to be getting anything much, maybe half-a-volt? Partly I suspected that screen is probably fine, but the inverter is stuffed – here it is, lurking in-place behind the front panel:

Power inverter for original screen - probably knackered

The connection on the left is the 5V and 0V connection from the panel – this is what we’ll use to provide the power for the backlight on the new display. The data and power connection for the display uses the bottom 14 pins on the connection, with the 15th and 16th pin taking 5V and ground respectively for the backlight.

As Don suggested in the thread, I connected a 1K pot (albeit linear, it’s all I had going spare) in series with the 5V connection to control the backlight – I nudged it down a bit from the maximum, and it’s probably a bit too bright still but it’s readable.

It took a bit of finagling to get the screen in place – it has to go behind the screw holes because the screen is thicker than the old one. The screws had to go in from the back, which was a bit of a faff.

New screen in place

Here it is with the front panel on:

S950 with front panel back on, screen glowing brightly

Looking loads better. Shame about the scratch through the screen, though not much I can do about that. It was only 75 quid when I bought it (including a massive box of discs) so I can’t complain really.

While I had it open I took some photos of the insides. Easy to see the eight voices on the top board.

View of inside S950 from the top

Getting a bit closer – loads of regulators attached to that chunky heatsink:

Top of power supply

Towards the back on the left we’ve got the power inlet, transformer and the MIDI board – PC900V opto represent.

Transformer and MIDI connection

And there’s this bit, caused me some trouble last time.

Jack board output and PCB

It’s all back together now and happily propping up a bunch of other relics.

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wiring horror, again

I make it hard for myself. I’ve spent a week or so of evenings soldering wires and still the PCBs aren’t even attached yet. Pfft. I’ll get there.

Dig the towel tho, it’s a classic.

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