Altitude

FYI, the setup_6581 has the LCD set to 4 not 5 like in the previous one

Don't need mine anymore so I though I would put it up here for sale or trade. Make me an offer. This includes: 1 x C64 PSU (tested), DIN7 Socket with wiring (mta connector on one side), PSU board with power-on LED header, 4x14V header, 1x 5V/GND header. This has been tested with a 4xsid setup and I will include some unused MTA connectors (the no crimp friction lock ones) Looking for MAX parts for CV or an 8580 I'm in the US (midwest) but will ship anywhere

I got some testing done today and so far so good. Reading 5/12/-12 and tested it today on the modifed SID board with success. Subjectively, the SNR was at least as good as the optimized c64 PSU. I'll hook it up to the spectrum analyzer next week and compare ;D I only had time to run one SID/Core pair with step B control surface so I have yet to run all 4, but thats next. The modification to the sid board was exactly like on the core, pull the regulator and rectifier, bridge the regulators in/out with a jumper, and supply +12 via available pin. I used the + leg of the removed recitfier which puts the power in on the corner of the board. Works perfect

for most things, it should not matter unless the cap is needs to be precise. For bypass and power filter caps, it wont make any difference other than the physical size of the part. here is some good reading: http://musicsynthesizer.com/txt/caps2.txt

The caps are for smoothing. There is a formula for calculating what you need for smoothing based on load, but I generally go overboard with over designing stuff, hence the 4 big caps (I may only use one for the -12). The idea is that you want to remove any oscillations in the power. The higher the load, the more pronounced they will be so the bigger the cap, the less the effect. The small caps are there since they charge quicker than the big caps. I'm driving both the 7812 and 7805 from the positive out of the rectifier so the draw there will be relatively large and the big caps should be necessary. The big honking resistor is to lower the voltage before hitting the 7805, otherwise putting 12V directly on the 5V regulator would make it fairly hot. I added diodes on the +/- 12 rails (per the 7912 sheet) to prevent a power up short since caps apparently short for an instant before charging and this would be bad for a the op amp i am driving. In TK's psu, notice that the 7809 pin 2 is connected not to ground but to the +5VDC line, therefore 9+5 = 14V

i'm wondering if the java apps would work

The tile cutting attachment with a fence would probably work pretty well

I'm sure its to beef up the 5 volt signal but even on the schematic it says you can go lower value if you need more room

damn. looks sharp as hell. Nice work

Kinda late into this one but: http://www.musicfromouterspace.com/analogsynth/SOUNDLABMINISYNTH/soundlab.html Very nice DIY synth with moog style filters and 2 osc's. Makes a nice match for midbox-cv

I only mounted the J11, the clock, and the resistors (probably more than i needed). The big cap, rectifier, small cap in the power circuit can go if your running 5VDC from your PSU. I think I also left off the opto (my box is at my shop so i'll verify)

I wont be using the c64 psu since i will need +/- 12V. The 7805 in the TO-220 can only go up to 1 amp and i am using a low current LCD so hopefully it will be enough

ball park figure? using 4x 6581's but i am most concerned with the 5V rail

I would get the one with the most speeds (some are only 3 speed) but for cutting slots, I would send it out and get it machined professionally. Long, straight anything by hand is asking for disaster. http://www.frontpanelexpress.com/ for the US and their main facility is in Europe, their free software is excellent

The Dremel is the way to go. I would also consider front panel express, if you just need the holes it's pretty cheap actually considering the time and results. My step C front panel (just the holes, no ingraving, thats about 150 holes) was $40

the brightness pot does work, but on my LCDs, it barely registers (this is true for the smash LCD)

Well I saw this at the shop I go to and figured I would give it a whirl. Results are WONDERFUL and its a no brainer to do. Mix the two parts with 12 oz water, heat to 120 F drop the board in and wait. The only thing to remember is to keep everything super clean (i tried to clean some etch resist marker in the right corner, bad idea). I would also add that this time was the first time using the Philmore Datek boards and I am much happier with the results than with the GC brand (which tended to over expose easily). I just used a laser printed mask and exposed it at 12 in for 10 minutes with a normal 100 watt bulb per the instructions

Very cool C64 overlay keyboard. someone should snap this up for their SID project Ebay link

could be a combination of both. miswiring killed one for me

http://www.midibox.org/forum/index.php?topic=6374.msg48464#new

interesting. the psu i'm working on has a power resistor on a 12V line after the smoothing caps before the 7805 which should drop it (according to alex who is also working on one) to about 7 VDC, which is more than manageable. I dont know how clean the 5V has to be since it is driving the digital side only

I did some work on this myself and here is a simplified +/-12 +5 V one. I added some protection diodes to the 12V lines so when they are used to drive op amps (which is the case for me) they will prevent the power up cap short. I also added spaces for more big caps. And the Trace Art: The regulators are shown flat but should be mounted vertically for use with heat sinks, i could not find a pin compatible to-220 package in the library so i just used those The Transformer I used was a Hammond 166L24 24ct VAC / 2 Amps (mouser p/n:546-166L24) and the power resistor was an 8 ohm 10 watt Xicon type 280-CR10-8.2-RC (mouser p/n:280-CR10-8.2-RC) I will be testing it on my SID x4 and get results up promptly.

You can click the traces and they will highlight what pins they are connected to. May make things easier to sort out

You cant see the trace on the GIF, dl the *.brd file and hide the top layers, there is a trace that goes to the from R1 to the 78L05. I made a board based on this and it works fine

um, what board is that? Those values do not correspond the the mhbp_burner_v1.brd file i have (its R10 and C8 on mine, and they do connect)