Simmons SDS 3 - DIY?

[elmegil]

xpmtl:

How hard is the SMT built? I have done one tiny bit of SMT soldering, a bunch of 1206 (I think?) bypass caps on a wogglebug.

I like the idea of 1U MOTM, since that's the format I use, but I'm a bit intimidated by all the tiny things in yours .

[THeff]

Hi elmegil,

I built xpmtl's SMD board and it went together very easy and worked the first time I tried it.

I would recommend three things:

1.) Liquid solder flux for the IC's, they will solder much easier. It doesn't take much, just a little dab on each IC pad.

2.) A good set of tweezers, cheap ones will shoot the part across the room if you are not careful.

3.) A magnifying head lens (depending on your age )

If your budget allows, a hot air solder/desoldering machine is really helpful for parts that have more than two leads.
I don't own this model but it will probably work fine. http://www.circuitspecialists.com/i-182127.html

Regards,

Theff

[elmegil]

Thanks THeff

I have the good tweezers (though I'm not sure offhand where in the mess that is my desk that they have wandered to) and I bought syringes (?) of liquid flux and I think solder too, along with a few schmartboards, because I accidentally bought the SMT version of the CA3140 a little bit back But I haven't actually used them yet.

I appreciate the advice.

[jmejia]

[xpmtl]

Well Tim responded already, building is not very difficult.

For the resistors/caps, put a small amount of solder on one pad, align the component and slide it in place as you heat the pad. Then solder the other end. For the ICs, use Flux and solder one pin first as you align the component with tweezers. After that solder the remaining pins one by one or use the sliding method ( look on Youtube, there a bunch of tutorials for soldering SMT).

I have a Hot air station but i find the results less clean than with a soldering iron. Usually components pop out of their place when i apply heat. I think my soldering paste is not very good. It's new tho (Chipquick™ water washable leaded)

As for my lack of updates lately, i had a car crash and i need to find/finance a new car so SDIY is a bit on hold... should resume mid cctober when i get back from holidays. I'll make a prototype of the frontpanel then and post the .fpd file on my site.
If anyone wants the file now i can PM it but you'll have to triple check it as it still has errors.

x.

[THeff]

Wow xpmtl,

Sorry about your car man! that stinks!
Hope you are ok?

Hang in there...

-Tim

[xpmtl]

Thanks Tim,

I'm fine, it was just crushed metal and a lot of paper work, waiting for the insurance company to pay back, ordering new car, etc...

I'll get the new car when i come back from holidays early october so things will settle down by then.

x.

[diablojoy]

SMT isnt difficult at those sizes
I normally do that size with a standard iron , normal solder and little blobs of bluetack to temporarily hold things in place while i solder the other end:lol: certainly quicker than thru hole

[silwerfeldt]

I just want to say thank you for all your hard work and I really look forward building my SDS 3. I´ve always wanted to tray it out...

Cheers

[jmejia]

Thanks! Been waiting (too long) on replacement FETs from futurelec to do final testing! Hopefully they'll get here soon!

[paulstone]

wow interest in this project and pcb's
great

[silwerfeldt]

Any news on the PCB´s?
Sorry for stressing but I´m so thrilled to know that maybe I´ll get to build a SDS 3 Clone!

Cheers and keep up the good fantastic work

[arnoid]

Any news ?

[duff]

Just wondering if this is still happening.

[DickyKnee]

Hi all,

I only recently came across this thread and got real exited and purchased some boards.

Ive been looking at the schematic, and see some potential improvements (if there is ever another design revision) since most people seem to be aiming to use this in a modular setup, with a shared power supply.

1. LEDs. Namely connected to the ground. The lfo led bothers me the most because its hard switching 10-20mA continuously onto the ground. better if it was connected to a rail. Or if crazy anal, also constant current sourced with a shunt FET to switch it. As much as I would like the LEDs, I'll probably leave them off my build because of this. Another thought with the lfo is to stick a bi-colour in the feedback around the Schmitt trigger.
2. The voltage rails being used as voltage references. The resistor in the noise source, pitch/offset/null pots. There is possibly some others.

It probably works fine as is, but good practice in modular design is to use the ground as a reference (not a current sink), use voltage references for other voltages and to use the power rails only for power. Much of this would not have been an issue in the original stand alone unit.

[n.d]

So, you know

BUMP!

[arnoid]

I recentley build 4 boards from xpmtl sounds very nice

Somebody knows how to add the Drum mic inputs + the Mic. sensitivity pot ?

[mono-poly]

weird i've built a couple of these boards but non of them did work

[arnoid]

Simmons clone containing 4x sds3 and 1x sds5 channel + some extra's finally ready

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[xpmtl]

Very nice Arnoid

I finished mine aswell, been waiting to do a panel for almost 2 years will post pics this weekend.


@mono-poly : what's not working exactly? we can help you troubleshoot if you want.