I have been working on building a pedal and wanted to build it using smd components and pcb's. The first requirement was to get all the switch gear on a single pcb that i could use in all the pedals i make.
This pcb has input and output jacks , psu jack, led, effect circuit protection and batt clip all on the pcb. the second pcb has the entire effect wth the pots . The two boards connect together with 4 wires that carry power + - and input output. I hope some of you have some good feedback on what improvements i can make and pro's / con's of what i am trying to do.
The first pic is the full unit from the top
[img][http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/29072008303.jpg.html/img]
the second pic is the switch board from the copper side and the effect with no pots
http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/29072008298.jpg.html
Sorry im having a bit of a prob uploading the pics
here is a link to the first pic
http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/29072008303.jpg.html
Incredibly neat build - I like the 4 wire thing. What's the effect?
This efect is a simple overdrive with gain tone and level.
(http://i90.photobucket.com/albums/k243/lenny1dog/29072008303.jpg)
(http://i90.photobucket.com/albums/k243/lenny1dog/29072008298.jpg)
that is B-E-A-utiful :D
Thanks for the comment Snufkin. i hope to improve on a few bits. not sure if i want to make them a one pcb affair or eep them seperate.
If i keep them seperate the any effect board i do will just connect to the main board with the same 4 wire. there is still quite a bit space in the box for the effect pcb. I am going to try and get a flanger in the same size 1590bb size case, only problem i think i will have is geting the bbd chips in a surface mount package. Does anyone know of a surface mount bbd chip ??
Nice built Ice-9,
Is that a true bypass? 3PDT? no mil circuit isn't it.... haven't tried smd yet :-\
Roger
@Rogeryu_ph - Yeah its a true bypass that ive used in the pcb with 3pdt. If anyone want the pcb pattern to make themselves i can post it up
Nice work.
The thing I hate about SMD is that film caps don't shrink like silicon and resistors do. You're stuck with having to choose either ceramic caps, huge nominally surface mount films, or a hybrid surface/through hole board.
Impressive! I'm envious of your packaging skills. :icon_wink:
Thats a good point about the caps i agree totally . Although i do have a 10uf tant smd on there and its not too big. The one thing i'm not sure about is the quality of caps in smd packages, i am using mostly ceramics which if i was to build a project using through hole caps i would prob use silva mica and film not ceramic for improved sound. I'm not sure if you can get silva mica in smd package ? and film are big as you say.
Ice-9, that's an amazing build :o
Did you solder the smd parts with a regular station or with special equipment like a soldering oven?
That is great !
All components were soldered on using a pair of tweezers and an antex tc 50 watt iron. I just run a flux pen over the pcb after etching it and touch the tip of the iron with solder and the flux does the rest. Its quite easy when you get a bit practice.
Not to say it must not be really hard [it looks like quite a few new tricks to this 'ol perf-dog], but you've proved to us it can be done, thank you for the details such as the iron and techniques used !
Your intuition and learning has allowed you to create a nice working OD, sort of a first around here {You probably saw the same youtube on working with SMD's that a member here was nice enough to show a link to?}.
Congradulations on your success with it !
Hi again !. If you have a link to the youtube video you mention i would like to check it out.
The way i decided to try out using smd was because ive done a few repairs to Dv equipment removing the likes of tsop48 pin chips and replacing them using the likes of a feeler guage (car tool for checking plug gaps) and a soldering iron, what i got from doing this was finding out that the key to success in removing / replacing smd components is , in my case down to using a good flux pen. It makes it easy to do.
What was hard for me to do was etching the pcbs well. I first tried the laser print on paper ironed ont the copper board, I got some half decent results but decided to try and make a uv light box from uv leds, that was total failure, so i bought a 8watt uv tube and things started to get much better.
Over the next few weeks i'm hoping to improve on all the pcb's and get a few different types of pedals made. If there is any interest in smd and nobody mind me posting some pictures of my results as i go then i will keep on posting some info here.
Thanks everyone that has looked in.
Quote from: Ice-9 on July 29, 2008, 09:26:01 PM
Hi again !. If you have a link to the youtube video you mention i would like to check it out.
Neh... The guy just did it by himself.
Great initiative !
Refreshing !
Yes, also a link to how to read those smd resistor and other component value ::)
Maybe you could use circuit cable and socket for easy replacement for head and mainboard such as replacing between a tubescreamer board and SD1 board though the only problem would be pot value. Is there an in-circuit detachable terminal for pot easy replacement?
Roger
I'm impressed with how small the SMD componets are. A bass fuzz would be invisible! :D
Great job Ice-9
Magnus Nordbye
Respect!
Man! That's impeccable!
That's the neatest thing I've seen in *ages*!
Congrats!
:icon_lol:
Quote from: R.G. on July 29, 2008, 07:33:38 PM
Nice work.
The thing I hate about SMD is that film caps don't shrink like silicon and resistors do. You're stuck with having to choose either ceramic caps, huge nominally surface mount films, or a hybrid surface/through hole board.
e.g. Farnell has:
http://industrial.panasonic.com/ww/i_e/21088/smd-film-capacitor_e/smd-film-capacitor_e/ecpu/index.html
Yeah ! i like your idea roger. Using a socket and plug on the wiring harness at one end will allow the quick swap of different types of fx board. I think i will keep the pots mounted to the fx pcb and just have the connection betwen two pcb's. thatway i keep the fx circuitry complete.
Thanks for the farnell link Snap. i will check out the uk farnell web site for these.
reminds me of those MOD boards
great job, do you use a typical soldering iron or a special one/modified one???
+
if i were you, id solder some jumpers across the back of the pots and wire it to the input jack ground
Yeah, i use a normal soldering iron , no mods just a standard antex 50 watt. Great idea about grounding the pot cases also. Something i totally overlooked.
Quote from: snap on July 30, 2008, 04:10:31 AM
Farnell has: http://industrial.panasonic.com/ww/i_e/21088/smd-film-capacitor_e/smd-film-capacitor_e/ecpu/index.html
Yeah, I know they exist. I use them all the time.
My point was that a film cap is roughly the same volume (length x width x depth) for a given value of capacitance whether it has PCB mounting pins or metalized end caps. So a 0.1uF film cap will be roughly the same volume whether it has pins or not. Perhaps even worse for the PCB layout guy, a through-hole film cap is always turned so it stands on the thin side on the PCB. For SMD, the cap MUST be oriented so the maximum-area side is down to ensure it is held firmly to the board. So an SMD film cap takes up as much or MORE of the board area than a through-hole cap of the same value.
This is particularly frustrating when a resistor has shrunk from a footprint of 0.1" x 0.4" (0.04in^2) to 0.08 x 0.05 (0.004 in^2), or by a factor of ten. And when resistors as small as 0.02" x 0.01" (0.0002 in^2) are available, a factor of 200 smaller.
0805 ain`t that large...
The 4-wire thing reminds me of the little Danelectro Fab series. Same deal with the switch and jacks on one pcb, and the effect on another.
One question: do you feel like the in/out jacks are solidly connected? In other words, would you worry about repeated plugging and unplugging causing them to come loose?
Wow, that is sweet!
Really nice looking pedal... my question is... why smd??? just for fun?
Quote from: puretube on July 30, 2008, 02:00:55 PM
0805 ain`t that large...
Unless my calculator has been making gross missteps, it is - 0.6376 nano-Acres, 0.258 nano-hectares, 2.58 mega-microns squared.
I'm pretty sure I have area in "hides" in here somewhere.... :icon_biggrin:
Nice job on the SMD build. I've converted a lot of my builds to SMD. Once I got the hang of how to solder the devices, etc, it actually goes fairly quickly.
The devices that are the biggest pain to me are SMD electrolytic caps. They come in seemingly endless varieties of sizes for a given value which, of course, changes the design. Plus, I find them to be the most difficult to solder securely. Tantalum caps are far easier to solder, at least for me. Mixing through-hole caps is easier still, but now the "back" (nee front) has components as well.
@ earthtonesaudio , The jacks and switch are secured to the metal case the same way a wired build would be meaning the pcb and solder joints take no pressure at all. the board is really susspended from the components rather than kepping the components in thier place.
@ waveman, I just bought a evh phaser from mxr and took it apart to check out the circuit and seen it was 99% smd and looked really neat , so i thought why not build an smd fx myself just to see if i could. Then i realised that it can give so much more scope as to what you can fit in a box (and the components are cheaper and there are no holes to drill in the pcb apart from the pots) now i have the smd bug and want to build them all like this.
I made 2 circuits for testing 1 smd and 1 normal components and to be honest i cant hear any difference in the sound from the 2
One more photo of the fully assembled and tested pedal. Just needs a paint scheme now. Spose its time to move onto a new pedal now. Hmm phaser or flanger ?or maybe a smd BSIAB2 poss with 3 band marshall style tone controls.
cya all in the next build.
(http://i90.photobucket.com/albums/k243/lenny1dog/31072008305.jpg)
Okay, one more question:
How did you get the Jacks/Switch pcb in the enclosure? Since the jacks stick through the sides, don't you have to bend the board quite a bit to get the jacks through the holes?
If you use those ALPS or ALPHA mini pots you can put several more knobs in there, taking advance on the tiny smd board!!. Very nice build!
The jacks are not the type that stick through the holes. they like up exactly with the inside of the case then a chrome threaded net scews into the jack internaly. i will post a pick of this when i get to my home pc.
The pots i have in there are alpha minipots and probs get 6 in total in there for any fx that need that many. Im thinking of doing a 3 band tone and gain and level next so that makes it 5 for my next pedal. I will see how that goes.