Interested in getting comfortable with SMT?

[garcho]

Thanks Perrow

[Perrow]

You're welcome

Please note that it is unverified, but, with seven components I guess you can double check it before committing to the build

[Perrow]

Went looking for something a little 'more' than an LPB-1 and the Big B*stard popped up on the 'show new replies page'. So here goes, totally unverified, SMD 386 drops in the empty space, through hole components on the reverse side (back of screen). Test for the value of 'VR1' and order a resistor of the appropriate value.



300dpi. Board measures 2.4 x 1.5 cm, 0.95 x 0.6 inches. I printed it to test the size of the SOIC-8 pads, it's sooooo small  

No, seriously, you won't believe how small it is before you've printed it, it's the width of my thumbnail and as long as 1.5 thumbnails.

Top row is input, 9V and out. Gain pot on the two pads in the middle and ground on the bottom.

[therecordingart]

Went looking for something a little 'more' than an LPB-1 and the Big B*stard popped up on the 'show new replies page'. So here goes, totally unverified, SMD 386 drops in the empty space, through hole components on the reverse side (back of screen). Test for the value of 'VR1' and order a resistor of the appropriate value.



300dpi. Board measures 2.4 x 1.5 cm, 0.95 x 0.6 inches. I printed it to test the size of the SOIC-8 pads, it's sooooo small  

No, seriously, you won't believe how small it is before you've printed it, it's the width of my thumbnail and as long as 1.5 thumbnails.

Top row is input, 9V and out. Gain pot on the two pads in the middle and ground on the bottom.

What program did you use for this layout? I want to do SMT layouts in DIYLC, but I don't know how to create parts.

[thelonious]

Went looking for something a little 'more' than an LPB-1 and the Big B*stard popped up on the 'show new replies page'. So here goes, totally unverified, SMD 386 drops in the empty space, through hole components on the reverse side (back of screen).

This is awesome, thank you!

[Perrow]

What program did you use for this layout? I want to do SMT layouts in DIYLC, but I don't know how to create parts.

I use DIYLC. The resistors and caps are just regular components (length = 2mm, width = 1mm for 0805). I adjust the regular pads (hole size 0) to fit my needs, the SOIC pads are actually two pads per leg, size 0.03 inch and on adjacent grid points - grid spacing 0.025. Did a Google image search for SOIC-8 and found that the legs are in fact 0.05 inches apart, so it's quite easy to adjust the grid setting to fit.

As Tayda doesn't stock SMT electrolytics or J201 I used regular through holes for those. I thought about allowing space for a trimmer but those are just so big I decided against it.

[bluesdevil]

Thanks for the layout, Perrow!! Only wrench in the works is having to figure what resistor should go where the trimpot would be used before ordering parts for the project.
I recall someone who goes by the handle "culturejam" made up a surface mount Tubescreamer pcb, I believe. Not sure if it was just for personal use or not, because I've never seen a layout for it.

[Taylor]

Well my goal was to get some SMD talk going and make some converts - looks like that has happened! Not sure then if the kit thing would go through but I will definitely resurrect some of my old circuits that no one built and do SMD layouts for them and post them here.

[garcho]

sounds good to me. once i was done being scared of SMT, i started getting excited 

[chromesphere]

It sure has Taylor.  I have even gone as far as making an SMD layout of the LPB1 for fabrication!  Only 6 boards (for practice) but the fab process is another new for me (a test run), and was actually not as hard as i thought it would be.

I've been thinking of trying smd for some time now.  Your post was the kick in the ass i needed

Thanks again,
Paul

[pickdropper]

I won't repeatedly spam this thread, but I posted a few extra SMT protos in the for sale section if anybody is looking to give SMT a shot.

Mods:  if it is bad form to post this here, please delete this (or ask me and I'll delete it).

[Perrow]

Thought I'd scan the bay for a "starter kit" and found this. 50 different resistors (x 30) and 40 different caps (x 20) for $10 + $1 shipping.

That's less than half a cent for each component 

Electrolytic caps kit search (check voltage so you don't get 10V ones). Looks like you can get a nice starter kit for $10 plus a few for shipping there as well.

[pickdropper]

The thick film resistor and ceramic cap seems like a decent deal, but I would verify that they are bagged or labeled first.  There are kits out there that come in binders that keep things straightened out.  Particularly the caps, which generally have no label on them.

Personally, I'd skip the SMT electros.  I always skip those in favor of Tantalums.