• Delta,  Isla Instruments

    Life & synths

    September has not been a good month in many ways. Firstly my partner has been in hospital for a week having some major surgery as a result of her having had cancer 6 years ago and A week before that my mum had a stroke and has been in and out of hospital. Suffice to say, I’ve really not had much in the way of energy or enthusiasm to do much with synths, but I have done some bit when I’ve had the beans. Quadrowave Quadrowave has fully functioning ADSRs for VCF and VCA, the VCF and VCA work, two LFOs are also working and the oscillators are working, it’s…

  • Delta,  Isla Instruments,  Synths

    Even more synth updates

    Things have been moving with synth projects this last month, first up the Quardowave card for the Isla Instruments Caladan has arrived, I’ve assembled it, checked power and got blink working on the CPUs. I still have to debug the VCFs but the other parts, like DACs and VCAs are the same as the OPL3 card I’ve been working on for Isla Instruments, so they shouldn’t be a problem. The next job is coding the CPUs and getting some sounds out.I’m looking forward to getting this up and running and making some sounds, it should sound epic. In other news the prototype voice holder for Delta has arrived and been…

  • Delta,  Isla Instruments,  Synths

    Synth updates

    Things have been getting a little better of late and I’ve got some of my mojo back, some. Firstly, I’ve been working with Isla Instruments on their Caladan synth, specifically the OPL3 card for it, this uses a bunch of new old stock YMF262 4 op FM chips and a multimode VCF and VCA. Originally it was 4 voices and has now been expanded to 6 voices. It’s almost done but I have a couple of features I want to add to the firmware yet.I have also been working on a voice card of my own design, I’m calling it the Quadrowave (until I can think of a better name),…

  • 100m,  Personal,  Retro Computing,  Synths

    What’s been happening?

    Well I failed at posting once a month, my bad. A lot has been going on since March. I’ve been talking to the new owners of Modal Electronics on and off, since September, and I just stepped away from it. My reasons? There are a few, but mostly because their vision and what I am passionate about in synths are very different things. There were a number of other factors involved, but I won’t go into them. I’ve also not been well, for the couple of weeks I’ve been having major chest pains that come and go, a few days ago I ended up in an ambulance on my way…

  • PDP11HackPlus,  Personal,  Retro Computing,  Synths

    Time flies

    It’s been a hectic few weeks, well, month. My mood has been all over the place, and generally trending down. But I have been doing some bits and bobs. I’ve been working on a couple of displays, something retro styled. I wanted to do something like the TIL311 but with a full alphanumeric character set in, so I’ve started on that. It’s slightly shorter than a regular EPROM, but the same 0.6″ wide. When I’m done coding it I’d like to coat it in resin, just to give it that classic TIL311/Retro display kind of vibe. I’ve got a few of these, so it’d be fun to do something with…

  • PDP11HackPlus

    PDP11 Hack+ Bus display

    Well I got the PCB and assembled it, and first off when I powered the board up it caused my PSU to go into over current protection. After a little investigation I realised I had grounded the left and right dots, which are not logic inputs like the rest of the chip for some reason, they are the cathodes of the LEDs. So I was basically putting a whole bunch of LEDs between 5V and 0V, oops. So having fixed that, it does indeed light up. The next problem is that I forgot to include the enable line for the memory so that it only displays memory data/addresses rather than…

  • PDP11HackPlus

    PDP/11 Hack+

    I’m really pleased to say that over the holiday I managed to get some time and built up my RAM/ROM/Text Display PCB for my DCJ11 system. First power up (just RAM) worked, I could write and read from the memory, YAY! Next up I added the display and that also worked (you can see the block on the right hand most character), however I couldn’t then write to the UART memory address, after a bit of digging I’d got my PAL code wrong for the memory address decoding. I forgot that the DCJ11, despite being a 16 bit chip, can only access 16bits of address. A quick bit of rework…

  • PDP11HackPlus,  Personal,  Synths,  TTL CPU

    Time & motivation

    I am still struggling with my mental health, though it is getting better slowly. I’m getting a bit more motivated and I’ve been some work for Isla Instruments, which is a refreshing change. I’ve had an idea for another synth, curse my head, so I’ve jotted it down and put it in the “laterbase”.My current plan is to get the Synth Voice module I designed completed and running (I have PCBs), work on the Isla Instruments project (which will be on going) and do some bits on Epsilon when I get stuck with that and need to free my mind up a little. I’ve put a self imposed ban on…

  • Uncategorized

    Mojo and Epsilon

    Things have been really bad for my mental health over the last month or so, to the point I even had to take some time off work because I can barely function. Some function is returning, but my mood is still very very low, and it’s exhausting. I have been working on Fusion 360 to figure out how to make sheet metal and how to make a case for Epsilon, so after some work here are some pictures. This picture shows the underside of the PCB assembly, showing 10 voice cards and one effects module. I’m glad I put these PCBs all together in Fusion before ordering them because a…

  • Personal,  Synths

    Better late than never?

    Well, It’s been a while and yeah I’m failing at updating this blog regularly. First an update on synth stuff, I’ve been working on a front panel for my synths, I’m currently fed up with the sound of the analogue synths I’ve heard (though I will say the GS e7 sounds amazing) and I want to build one for myself, this isn’t a product I plan to sell. I’ve designed the voice, using two SSI VCO chips and an NJM2069 VCF/VCA (as I have a few), I’ve got the PCBs for that but haven’t got around to building any yet. The front panel also uses a lot of the same…