20 questions from a noob

[cbomb]

How’s it going everyone? This is my first post here

I have made it my goal to build a MBSID with the modular kits from SmashTV. I bought a DIN kit, a SID kit, a CORE kit, a 2X20 LCD, some MIDI jacks, some buttons and a rotary encoder. I bought the kits from Smash obviously, and I used some parts listed here (okay, I really just got the buttons using this thread, but I plan to use this thread for most of my project if I can):

http://discourse.midibox.org/t/topic/13533

PEC-11 encoder:

http://www.mouser.com/ProductDetail/Bourns/PEC11-4220F-N0024/?qs=OfLg%252b8nW%252blb3ykxT2911aA%3d%3d

The parts list in the first link will probably be my main reference for parts when I start to plan my complete control surface. Right now, I will be building the “minimal control surface”. I think I have bought everything I need for that, and I know I at least have everything to access my unit controlling with a computer only.

The only part that I’m slightly worried about is the LCD which I bought without really making sure it would work:

http://www.shopeio.com/inventory/catalog.asp?q=AMC2002C-B-T6WTDR&cat.x=0&cat.y=0&action=3

I see no reason why it wouldn’t work, but from now on I will only try to order parts that have worked for other people. My skill level with electronics is very very low, so I will be relying on the words of others.

My stuff is not here yet, but I have spent the better part of the last few days researching and compiling information. I think I have a general understanding of how this stuff works but there are a number of areas that are not entirely clear to me. I am asking this now, because I want to have the PSU licked when I am building the modules.

I have a c64 power supply that I plan to use. I have looked at the PDF (link below, you’ve seen it before I’m sure) and everything. I am not quite sure what I am looking at there. Do I have to build this “optimized” circuit even IF I am using an original c64 supply? What exactly do I need in addition to my c64 PSU? In my mind, I only need 2 switches and a jack for the power connector. The answer is probably obvious, but I really don’t know how to read those symbols on the schematic. Is there a list of necessary parts to build this, if I do indeed need to build it? Sorry that I am asking to be spoon-fed, but all other information seems to be spelled out very plainly. This leads me to believe that it is probably very simple.

If this is relevant, I have a 8580R5 SID and a 6582. Do they have different requirements like the 6581? I might use them both eventually.

"I did some experiments with different PSU and regulation circuits, and finally found out that re-using the power supply which came with the C64 is the best solution. Not only that most users already own such a PSU if they canibalized the SID from an old C64… the main reason which qualifies this PSU is, that it already contains a 5V regulator for higher currents (so that the 7805s of the core modules can be removed), and that it provides a separate AC output which can be used to provite an unregulated voltage for the SID module:

http://www.ucapps.de/mbhp/mbhp_8xsid_c64_psu_optimized.pdf"

Also, I am very curious about how you guys are installing your control surfaces. Do most people use the CS PCB from smashTV? Will this CSPCB work fine if your MBSID is modular with kits rather than the MB-6582 PCB? Is it generally considered a bad idea to just mount your buttons, encoders, LEDs, and LCD on whatever you want and wire the various modules to them accordingly, instead of using a PCB?

Again, I apologize if any of these questions seems silly (also for the length of this post :)), I am trying to understand this on my own, but this stuff has been nagging me. I would certainly appreciate any help, as I already appreciate all these amazingly useful sites (midibox.org, ucapps, smashtv, etc.).

[Imp]

Welcome on board!

The Lcd should work, as it is quite similar to the one i used.

The shematic for the optimized psu is meant as an (necessary) addition to the c64-psu.

The c64-psu puts out regulated 5V, which is fine as it is for the core(s). It also puts out 9V AC(<–) which has to be rectified (part x1) and regulated to 9v DC(part 7809).

These 9V then get added to the already present 5V to have 14V DC. While this is meant to provide enough voltage to get regulated 12V for the older SIDs, it can also be regulated down to a stable 9V again, which happens on the SID-modules.

I think, most people who take the modular route also build the CS on breadboard.

It’s possible to combine smash’S ( Wilba’s actually) CS-pcb with other modules, but it’s usually used as part of a mb-6582.

Keep in mind, that you can always upgrade your CS later on!

[cbomb]

Thank you for the welcome and reply Imp! I can’t wait to jump in and start building. It looks like I have plenty of time to think about this power supply thing, 'cause my kits will not be sent for a long time (at least if the “order status” page is right). So, it looks to me like there is a wide variety of PSU solutions out there.

“which has to be rectified (part x1) and regulated to 9v DC(part 7809)”

Does this mean I need a diode/rectifier, “regulator”, 2 fixed capacitors, 2 nonpolarized capacitors, an LED (I will use my own, I still want my C64), 200 (200 what?) resistor, and a 5 pin connector? I think I just need help interpreting the schematic. I just used this is a reference:

http://picsdigger.com/image/0114bddd/

[Imp]

Since the PSu provides 5V Dc, u can leave out the rectifier on the core and use it for this circuit.

You’ll need one additional 7809 and these caps. The size of the resistor depends on the LED (which is optional btw.)and it’s desired brightness. The Value means 220Ohm.

The plug is a Din-plug with 7 pins, but you could also cut the cord and use any plug/socket combination you like, as long as it has at least 4 pins.

[cbomb]

Okay I think I’ve got it now. I spent the better part of the day scouring the forums and educating myself on schematics. I appreciate you patience.

edit: out of the 7 pins, only 4 are used? And, the ultimately get connected to 14 VCD, the LED, and 5 VDC? Those symbols on the schematic (14 VDC, LED, and 5 VDC) represent the four pins on the connector that are used?

[Imp]

I was referring to the c64-powerplug (lower left corner), which has 7 Pins, but only 4 of them are connected to the circuit.

The symbols on the right of the cicuit (14vdc, 5vdc) represent the outputs, which can be wired to another plug, or directly to the LED/ to the Core/the SIDs, if the circuit is inside the same enclosure as those modules.

[cbomb]

Yes, i have a hard time making myself clear. I knew what you were referring too, but you confirmed my suspicions about 14vdc, 5vdc, etc., thanks! I will try not to post anymore until I’ve attempted to build thanks again

[cbomb]

Hello once again. Yet another annoying question about the c64 psu optimized. The schematic for it does not indicate voltage for the 330nF or 100nF caps. Does this matter? I went ahead and ordered a variety just in case. I got this 7809 from Mouser as well:

http://www.mouser.com/ProductDetail/ON-Semiconductor/MC7809CD2TG/?qs=sGAEpiMZZMtqO%252bWUGLBzeFF3p4WDJW2G

These caps are extremely cheap, so I feel okay in

taking the risk and buying things I won’t need. Apparently, this company takes forever, they have bad communication, and they mess up orders, but they are indeed legit:

http://www.futurlec.com/

Does anyone have experience with Cables and Connectors inc.? I got a 7 pin DIN female chassis mount from them at a pretty high price. I’m trying to avoid cutting my c64 psu cord.

Any info would be greatly appreciated…am I in the ballpark with these parts (especially with the caps and 7809s)?

7809T 7809T - 9V 1A Positive Regulator (LM7809) 1 $0.30 $0.30

C00033UT 0.33uF 35V Tantalum Capacitors 1 $0.22 $0.22

C100UMC 0.10uF (100nF) 50V Multilayer Ceramic Capacitor 4 $0.06 $0.24

C2200U16E 2200uF 16V Radial Electrolytic Capacitor 4 $0.35 $1.40

C2200U25E 2200uF 25V Radial Electrolytic Capacitor 2 $0.50 $1.00

C330UHM 0.33uF 250V Mylar Capacitors 1 $0.30 $0.30

C330UM 0.33uF 100V Mylar Capacitors 1 $0.12 $0.12

C330UMC 0.33uF 50V Multilayer Ceramic Capacitor 1 $0.20 $0.20

C330UPF 0.33uF 100V Polyester Film Capacitors 1 $0.15 $0.15

Subtotal $3.93

Shipping $4.00

Total $7.93

[philetaylor]

Hi.

With capacitors, the voltage is it’s recommended maximum operating voltage but there is no problem using higher voltage caps on lower voltage circuits.

With electrolytics, I tend to use 16v caps for 5-9v circuits and 25v ones for 12v stuff. I never like to run things near their maximum so go with the highest rated voltage one that fits on the PCB. With ceramic, mylar and tantalum ones, these tend to be much smaller anyway.

Cheers

Phil

EDIT: Yes that 7809 looks fine

[cbomb]

philetaylor, thanks for the help! I wouldn’t get anywhere without you wonderful people.

cheers

[julienvoirin]

just an advice (from a confirmed amateur midiboxer) : get a cheap multimeter (10 bucks, numerical display) to check you have the right voltages to avoid frying your so rare SID chipsets (and the PIC too as it is preprogrammed)

it will also be very useful to debug, most errors being a bad/wrong soldering between +5V lines and the ground. To know if there is a short between 2 points (or lines) put the multimeter in “bipbip” mode or DIODE mode (it displays something like 001 is there is connection, error if not)

test all your voltages before stuffing the IC (PIC, SID, 74HC165, 74HC595). if it is OK, plug them and everything should work.

Get coloured flat cable too, it helps a lot to better understand what points are connected together (instead of grey one)

[cbomb]

Yes, I got a multimeter (with a speedometer-like indicator) last week, I’ve been learning how to use it. By colored flat cable, do you mean ribbon cable? I got a few feet of 16 pin and connectors from smashtv…

I’m still trying to learn how power makes its way through this device, I think that it (power supply/distribution) will be my biggest hurdle. Thanks much for the advice…got any more?

edit: This is by far the most ambitious project I’ve ever had, but I think I am meticulous enough to get it right. I’ve been studying and researching everyday, but I lack common sense in electronics. As my project goes on I will be taking pictures and seeking approval from you experts (if you would be so kind), hopefully before doing anything potentially harmful to my precious SID.

Thanks for the advice, julienvoirin!

[julienvoirin]

yes ribbon cable, sorry french abuse

Commodore supply : 1 pin is +5V, another is ground, the 2 others deliver 12V AC (from memory) design the circuit on your board like on this schematic :

http://www.ucapps.de/mbhp/mbhp_8xsid_c64_psu_optimized.pdf

If you do not have one, just get a 9V DC PSU and use a common ground for 5V and 9V regulator. Derive the tension of the 5V regulator AFTER the 9V regulator. Be carefull, the 7805 will be rather hot as it must eliminate a lot of energy (9V->5V drop). In this case, only one 2200uF and 330nF but two 100uF and 100n

for the power switch find DPST (double pole = bipolar = 2x3 pins under the switch)

[julienvoirin]

btw you don’t have to use 7pin DIN connector : only 4 pin DIN is necessary if it is cheaper. remember, you do your own connector

avoid 5 DIN for the supply as you could plug it in MIDI ports hazardly

[cbomb]

Hello once again everyone. My kits from smash arrived a few days ago, and I decided I would chill on it while I was waiting on more supplies and parts for my optimized PSU. Well, okay, I did go ahead and solder up a DOUT, just 'cause it seemed like a good way to get warmed up and everything. In my eagerness I used my 15W/30W “700 degrees max” iron, and my 60/40 .32" solder (my 63/37, .50" solder seemed too unwieldy, and my fancy iron is in the mail). I tried very hard to give the joint enough time to “set” without it really moving. edit: is it generally considered bad practice to use 60/40? What about the cheap iron? Is the danger that it could get too hot? When they say it reaches a maximum of 700 degrees, do they actually mean that? Another annoying PSU question: is the c64 PSU optimized pdf file on ucapps only for if you are using 6581 SIDs? Why would I have 14VDC for a 6582 or 8581, when those chips only seems to use 9V (correct me if I’m wrong!). Okay, I guess the regulator (7809) will take care of that? Do I leave the 7809 for my 8580 SID module UNSTUFFED like I do with the 7805 on the CORE?

I felt like it went fairly well, with just one immediately noticeable mistake. I mis-soldered (phone rang for me!) and almost shorted two joints with a big blob of solder. I tried to desolder with braid, and it seemed to work…only I think I burned a part of the board where the blob once was! There’s now a nice gob o’ black stuff there (which I assume is melted PCB). I was thinking it would be fine, but I wanted to know if this could cause any serous problems, and if it could be easily fixed…I’m sure it’s not hard, but a newb I am.

Now, the melted spot is very hard to see in these pictures, but it is visible…It’s the lower row of the resistor network between R1 and R2.

…can ya see what I’m talking about? It’s that thing that looks like a shadow, toward the middle of this shot, one of the closest joints.

I will try to get my hands on a better camera. Also, I hope this thread doesn’t become too annoying. It might eventually prove to be very helpful to others though, and I will try really hard to keep my questions informed. but I would also like to do a general documentation of this thing.

edit: so, I found some useful links that basically told me to do a continuity test and how to fix severed traces and stuff:

http://forums.techpowerup.com/showthread.php?p=1838803

[Smithy]

Looks like it might be okay, once it hasnt burnt through the track itself (the tracks are the green lines on the pcb).

A track basically is a line of copper underneath the green (silkscreen) part of the pcb, that carries the current.

Once you havent broken the track it should be fine.

Use the continuity function on your multimeter, to test between the solder point near the blob, and the next solder point on the track.

If the track is okay, your multimeter should beep if it has the beep function.

Touch the two probes together first to see if it has a beeper.

If it doesnt have a beeper, then the resistance value should drop to 0 eventually, (it might stay at 1 for a while).