technobreath - All synth related

[technobreath]

Album by technobreath
Gallery category: members-gallery

Album about my midiboxing life

Update: 2019: This gallery is very old. Do not pay too much attention to it. :) I have other stuff going on that may happen to be seen here one of these days :).

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StereoSID Case 1

Picture shows a concept drawing. It is pretty much the way it will look like when I’m done. Only thing is buttons and knobs will probably be a bit different. I might use transperant waldorf knobs for the pots / encoder. buttons will probably be tact.switches as seen on MB6582.<br /><br />Case is gonna be painted in matte black color, and in addition some areas with thick black latex coating (as seen on cell phone silicone protectors for example).<br /><br />8 bank sticks is inside the case.<br /><br />Some sideglow fibercable is also finding it’s way in there somewhere. Just have to figure out where :).

StereoSID Case 2

In the front the two green areas under there represents ventilation openings. Either they are gonna be cut out in strip shaped holes or I’m gonna put in some fine mesh stuff in the holes as they show on the drawing.<br /><br />The area above the vents is gonna house the headphones jack and a volume control for that.

StereoSID Case 3

The back panel is a little bit inside from the back of the box. To save space in studio and save cables and connectors on gigs. They will be as far into the box so only the cable is poking out from the back if you look down on the back. The plug itself will be hidden / protected under there.

StereoSID Case 4

A top view just to illustrate top shape in the best possible way.

Heatsink

Here is a special pic for you m00dawg :). Here you can see the tracks on the back of the heatsink to snap in the clips that secure the vregs to it :).

PSU

Well. Another PCB design of the PSU for the StereoSID. I thought I was done with the last one, but critic voices told otherwise :). So Here it is, hopefully the final version. More compact, looks tidier, negative vreg on the far right instead of in the middle. etc etc. Please tell me what u think of it :).

PSU board Closeup

OK. Second of these board I etched. The first one was kinda dirty, soldermask didn’t look good etc - in short - it worked very good, but I didn’t like it :P…<br /><br />The other picture will explain how I did the soldermask.

PSU board and vaseline

PSU board together with the good stuff.<br /><br />When I had etched the board I cut the tip of a q-tip diagonally, so it was sharp and pointy. Then I use it to apply the vaseline to all the pads. A rather blacksmith kinda way to do things, but certainly worked well as you can see. It took great care with the q-tip to not spill vaseline all over the place.<br /><br />When the pads were masked with vaseline, I carefully sprayed the soldermask on. Let it dry, then let it dry even more under my wife’s hairdryer - then I carefully tried to remove the vaseline to see if I could remove it without harming the soldermask (I wasn’t quite sure it was all set yet). But it was, and I just used the q-tips to remove the vaseline, and then washed it with soap and water to remove the rest of that good stuff.<br /><br />The results you see here. A little unprecise with the masking of the pads (too much spill) but I am really pleasd with the results.<br /><br />The soldermask is one of those "solderthrough" spray-on soldermasks, but smash told me it was much work cleaning the iron during soldering through the mask, so… that is why I did it like this. No tip cleaning / tip-ruining :).<br /><br />Now it only lacks holes. Smallest drillbit I god is 1mm. Too big for the smaller components, and it can be difficult to fill all the smaller pads, and not just half the hole, because it is too big, but with a bit of practice and care it goes just fine. 1mm is about the smallest drillbit the chuck on my drill will accept too, so I gotta make it work ;).

mb6582 panel

Well, here’s my version of Wilba’s great layout. In the files available from him, the graphics were all made by lines and curves and what seems to me to be adapted to some kind of engraving process.<br /><br />With some tips from Wilba, this design is a complete redo of the graphics. Holes are the original ones, but this file contains normal text wich one can change size and font type for without much effort. This also makes it perfect for silkscreening or printing.<br /><br />Based on what I know about silkscreening, you will not be able to do the blured outline around the LCD with silkscreening. The rest of the graphics is totally doable. However, I’m not personally using silkscreen, but a printing process that in short is printed graphics on the back of acrylic panel.<br /><br />I’ve sent this layout over to the printshop I use, and will get an estimated price for a completed panel.<br /><br />I realized a couple of days ago that it is the CS panel that were keeping me from completing the synth, as soon as I have made a suitable powersupply that is, so now that it’s autumn here, I found it about time to do something about this :).<br /><br />So this is the result.<br /><br />Any comments is welcome.

Crowbar Module

Crowbar addon module for my mb6582 PSU.

StudioConstruction1

Electrical work

StudioConstruction2

Dad helping out

StudioConstruction3

temporary seperating wall, due to come down when I move into the house.

StudioConstruction4

some snakes for pooowar

StudioConstruction5

12ch snake going into the wall

StudioConstruction6

outlets - power / data right beneath the desk to come.

StudioConstruction7

Corner

StudioConstruction8

sidewall

StudioConstruction9

sidewall2

ENC CS8

A very simple board with 8 encoders. Is supposed to be fitted on the frontpanel of my MB64E. I have some waldorf knobs with this destination.

ENC CS8 Board

Here’s my latest creation. A sandwitch of encoders and smd leds. Almost finished, only thing missing is the smd resistors.<br /><br />Check out my blog entry for more pictures. The buttons have nice green backlight from the upper pcb :).

IBM RackX2

Ahahaha, I took a trip to my bro’s basement and thought I’d shoot a picture of my rack cabinet :P. Here is two IBM racks. One is mine, and one is my brother’s. We got them for free from our ISP - we know a guy who works there.<br /><br />Each containing power distro built in, and UPS.<br /><br />We didn’t know they were so huge when we went to get them, but I’m sure I can find stuff to fill it with when I take it home :P. If nothing else, I can always make a 30 unit panel with blinking leds hahaha.<br /><br />It is about 1.20m deep - full height - about 190cm high. Solid steel with weights @ the bottom - each cabinet weighs several hundred kg. Crazy.<br /><br />Thought I’d fill it with servers and audio stuff for my future studio. Then I need to find out what to do with the spare half of it hahaha.

8Pre

A relatively and surprising low amount of belly-butterflies while unboxing the 8PRE. It has been sitting in its box all day in my workcar, so it’s the first time in history that I haven’t opened a package in the car outside the post office :D. Anyway, I think the lack of all that anticipated excitement is due to the fact that the TI firewire controller hasn’t arrived yet, and will not for a few days either :(. Out of stock in all the usual webshops until today. Either that, or they don’t have TI chipset based controllers…

goodies

Right next door to my office is a musicstore, and it was easy to burn off $160 on cables and strings for my guitars :D. Short way in there, money short took the short way out

1

Cleaning up the studio and installing new shelf on top of the bench.

2

Setting up some of my mics in the studio.

3

My very heavy, old bass guitar. It hangs mostly on the studio wall.

4

My other guitars.

SMPSU5V

Here’s a switcher board. This is gonna be my prototype, but I haven’t got all the parts yet. Anyway - the board has place for enough smoothing caps to acommodate pretty high current draw. Rectifier bridge has place for pretty big diodes. The vreg comes in 5 and 3.3 volt versions, and is pin compatible with 78xx vregs. So 1 or 2 smoothingcaps / diodes / vreg can be adjusted to specific needs. I hope it works, because what attracts me to this is the high input voltage range. No need for mor than 1 transformer even if you are making a 5 and 15v power supply. This is part of my “modular” supply.

Bankstick x8

I just saw a thread on bankstick in the forum. thought I should post this. I made it a while back, and it has sort of been sitting in my eagle project folder since then. If anyone want the files, just send me a PM :).

[Hawkeye]

Re: StereoSID Case 4

Looks interesting! How do you plan to create the plastic case with these irregular angles?

[technobreath]

Re: StereoSID Case 4

The plastic is a lie. There is no plastic, there is only fiberglass!

Nah.. Gonna make a model in wood, then make a mold with fiberglass, and then I’m gonna make the actual case from the mold also in fiberglass. Pure handwork, painfully timeconsuming

EDIT: Oh, I’m making a two part mold. One on top and one on the bottom. Should work.

[Hawkeye]

Re: StereoSID Case 4

Cool, that will be a unique case!

What kind of insulation layer/chemical do you use to avoid the fiberglass layers (probably hardened with epoxy) from sticking to the wood model?

Greets,

Peter

[technobreath]

Re: StereoSID Case 4

I’m not using epoxy, as it is more expensive (at least around here) than polyester. So I’m using fiberglass armed polyester as building material.

For keeping the mold free from the case itself I use a “release” fluid that is made for it (almost like clear coat) but mostly I just clearcoat with automotive paint and wax it with vaseline inside the mold and go from there

[Hawkeye]

Re: StereoSID Case 4

Thanks & good luck

[technobreath]

Re: Heatsink

I have about 2 meters of this kinda heatsink ready to cut to me needs :P. Should be sufficient for cooling some tiny vregs, no? hehe.

[technobreath]

Re: PSU

• Massive amounts of thanks goes to SmashTV & Co for all the nice tips on psu design. Not that I claim it’s good enough for them to put their name on it hehe, but they have been nice enough to look at my crazy ideas Thanks

[Shuriken]

Re: PSU

Looks good. Just make sure you don’t connect all the IC to one big heatsink. The metal backside of the 7915 is not GND.

[technobreath]

Re: PSU

Thanks.

/me knows :). Thanks for watching out for me though :). I use clips to attach the cases to the heatsink, and also isolation rubber.

I just started soldering the board today with the components I got laying around, the bridges, the small caps, and the vregs 9 and 5v. The rest is probably delivered today, but it’s too late to do something now.

Oh, I tried a solder through spray on mask - lets see how that works out.. :).

[Shuriken]

Re: PSU

Ah, i have a can of that here. A green mask. But haven’t tried it yet.

[technobreath]

Re: PSU

One board scrapped, new one made. I wasn’t quite satisfied with the way the soldermask turned out. :). Pics to follow.

[nebula]

Re: PSU board and vaseline

I really like the look of this. What is the name of the soldermask product? There aren’t a lot of spray soldermasks on the market here.

Thanks

[technobreath]

Re: PSU board and vaseline

yo nebs, thanks

The brand name of the solder mask is Bungard GreenCoat. Here’s a linky to the datasheet: http://www.krepro.no/index.php?dispatch=attachments.getfile&attachment_id=271

Was a bit spendy, and u wash it off with alcohol or acetone, so cleaning with that afterwards is a no no. But for small boards it works well. However, I really recommend u mask up the pads somehow - for example with petroleum based vaseline like I did. Then u can just wash it off with soap and water afterwards. Soldering iron and nose / brain doesn’t like to solder through this even though it’s very possible.

Imho this solder mask is more a cosmetic mask than a real solder mask, and I’ll probably not buy another can when it is empty. By that time I’m probably ordering the prototypes. But for a great look at a simple homemade board, it is super, as long as u know of it’s limitations :).

[Hawkeye]

Re: Crowbar Module

Nice!

[technobreath]

Re: Crowbar Module

Clone of your crowbar Though on my quest for perfection I found a IC to more acuratly control tripping of the crowbar. I’m sure it’s all hysteria and lots of over-perfection talking, but I read all over the net that this basic circuit is kinda hard to control at very low voltages… But I’m sure it works fine hehe. But just for the fun of it I’m exploring IC based design for this as we speak… lets see how it turns out… datasheet for the IC: http://www.onsemi.com/pub_link/Collateral/MC34161-D.PDF

[jojjelito]

Re: Crowbar Module

Now, ain’t that a nice-looking little PCB. Level-up with red SMT LEDs for broken fuse indication. I found such a board at work today and one of these day’s I’ll clone that.

But, this is far easier to service. Kudos!

[Shuriken]

Re: Crowbar Module

Nice find technobreath! I was looking for an up-to-date replacement for the MC3423.

The above circuit will do. But the problem with zeners is they only come in certain values.

So for example a 12.6V zener kicks in if the voltage exceeds 5%.

However the 5.6V zener kicks in after 12%. Which could already be fatal.

[technobreath]

Re: Crowbar Module

I’m drawing up some schems for this IC based solution now. This IC seems very promising the more I look into it. However, I have certain issues trying to wrap my head around how it really works. I’m soon there though ;). This chip, however is particulary interesting since it can do voltage window comparing. The undervoltage condition detection is a really interesing bonus. I’ll try and come up with a design that trigger the SCR at precise over voltage conditions, and also a autoshutdown of all rails at under-voltage condition. I have done an experimental PSU schem some months ago to learn about how to achieve these functions using basic components. The huge drawback to this was that the design had much more discrete components, and many comparator ICs. It also provided seperate vref from a seperate ciruit. This IC seems to have all of this built in, and I only need 3 resistors for each of the ICs to set the window for it to operate in normal state. This IC also makes it easier to incorporate these status LEDs jojjelito asks for, though I’m not sure how interesting such leds really would be. A single LED that is green when all rails are operational and that is red if a fuse is gone would probably be enough for me. Those 5x20mm glass fuses is easy enough to visually confirm broken or not. I try to keep the design as simple as possible… In the final design I will pobably use panel mount fuse holders, to make it way easier to change them if they blow. Any ideas to this IC based design is very welcome.

[technobreath]

Re: StudioConstruction1

Bag on the window is there because it’s broken. And why state this obvious fact? My grandma who lives in the house for the time being forgot to bring her keys and locked herself out. When she got home, she knew I was about to replace that window anyway, so what did she do? Crushed it, removed all glass from the frame (till she bled) and crawled in haha. it’s about 30x35cm hole.