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The New Hotness

  • AD8310 Log Amp Module: Sidesaddle Bracket

    This little bracket attaches to a proto board holder, with holes for M3 inserts to mount the AD8310 log amp module:

    PCB Side Bracket - 80x120
    PCB Side Bracket – 80×120

    Thusly:

    AD8310 module bracket on proto board holder - component side
    AD8310 module bracket on proto board holder – component side

    The OLED display looks a bit faded, which seems to be an interaction between matrix refresh and camera shutter: looks just fine in person!

    Not much to see from the other side:

    AD8310 module bracket on proto board holder - solder side
    AD8310 module bracket on proto board holder – solder side

    I should have included an offset to slide it a bit forward; then I could mount it on the other end with clearance for the Nano’s USB port. Maybe next time.

    The OpenSCAD source code as a GitHub Gist:

    // Test support frame for proto boards
    // Ed Nisley KE4ZNU – Jan 2017
    // June 2017 – Add side-mount bracket
    Layout = "Bracket";
    ClampFlange = true;
    Channel = false;
    //- Extrusion parameters – must match reality!
    ThreadThick = 0.25;
    ThreadWidth = 0.40;
    function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);
    Protrusion = 0.1;
    HoleWindage = 0.2;
    //- Screw sizes
    inch = 25.4;
    Tap4_40 = 0.089 * inch;
    Clear4_40 = 0.110 * inch;
    Head4_40 = 0.211 * inch;
    Head4_40Thick = 0.065 * inch;
    Nut4_40Dia = 0.228 * inch;
    Nut4_40Thick = 0.086 * inch;
    Washer4_40OD = 0.270 * inch;
    Washer4_40ID = 0.123 * inch;
    ID = 0;
    OD = 1;
    LENGTH = 2;
    Insert = [3.9,4.6,5.8];
    //- PCB sizes
    PCBSize = [80.0,120.0,1.6];
    PCBShelf = 1.5;
    Clearance = 2*[ThreadWidth,ThreadWidth,0];
    WallThick = 4.0;
    FrameHeight = 8.0;
    ScrewOffset = 0.0 + Clear4_40/2;
    ScrewSites = [[-1,1],[-1,1]]; // -1/0/+1 = left/mid/right and bottom/mid/top
    OAHeight = FrameHeight + Clearance[2] + PCBSize[2];
    echo(str("OAH: ",OAHeight));
    FlangeExtension = 3.0;
    FlangeThick = IntegerMultiple(2.0,ThreadThick);
    Flange = PCBSize
    + 2*[ScrewOffset,ScrewOffset,0]
    + 2*[Washer4_40OD,Washer4_40OD,0]
    + [2*FlangeExtension,2*FlangeExtension,(FlangeThick – PCBSize[2])]
    ;
    echo(str("Flange: ",Flange));
    NumSides = 4*5;
    WireChannel = [Flange[0],15.0,3.0 + PCBSize[2]];
    WireChannelOffset = [Flange[0]/2,25.0,(FrameHeight + PCBSize[2] – WireChannel[2]/2)];
    //- Adjust hole diameter to make the size come out right
    module PolyCyl(Dia,Height,ForceSides=0) { // based on nophead's polyholes
    Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);
    FixDia = Dia / cos(180/Sides);
    cylinder(r=(FixDia + HoleWindage)/2,h=Height,$fn=Sides);
    }
    //- Build things
    if (Layout == "Frame")
    difference() {
    union() { // body block
    translate([0,0,OAHeight/2])
    cube(PCBSize + Clearance + [2*WallThick,2*WallThick,FrameHeight],center=true);
    for (x=[-1,1], y=[-1,1]) { // screw bosses
    translate([x*(PCBSize[0]/2 + ScrewOffset),
    y*(PCBSize[1]/2 + ScrewOffset),
    0])
    cylinder(r=Washer4_40OD,h=OAHeight,$fn=NumSides);
    }
    if (ClampFlange) // flange for work holder
    linear_extrude(height=Flange[2])
    hull()
    for (i=[-1,1], j=[-1,1]) {
    translate([i*(Flange[0]/2 – Washer4_40OD/2),j*(Flange[1]/2 – Washer4_40OD/2)])
    circle(d=Washer4_40OD,$fn=NumSides);
    }
    }
    for (x=[-1,1], y=[-1,1]) { // screw position indexes
    translate([x*(PCBSize[0]/2 + ScrewOffset),
    y*(PCBSize[1]/2 + ScrewOffset),
    -Protrusion])
    rotate(x*y*180/(2*6))
    PolyCyl(Clear4_40,(OAHeight + 2*Protrusion),6); // screw clearance holes
    translate([x*(PCBSize[0]/2 + ScrewOffset),
    y*(PCBSize[1]/2 + ScrewOffset),
    OAHeight – PCBSize[2] – Insert[LENGTH]])
    rotate(x*y*180/(2*6))
    PolyCyl(Insert[OD],Insert[LENGTH] + Protrusion,6); // inserts
    translate([x*(PCBSize[0]/2 + ScrewOffset),
    y*(PCBSize[1]/2 + ScrewOffset),
    OAHeight – PCBSize[2]])
    PolyCyl(1.2*Washer4_40OD,(PCBSize[2] + Protrusion),NumSides); // washers
    }
    translate([0,0,OAHeight/2]) // through hole below PCB
    cube(PCBSize – 2*[PCBShelf,PCBShelf,0] + [0,0,2*OAHeight],center=true);
    translate([0,0,(OAHeight – (PCBSize[2] + Clearance[2])/2 + Protrusion/2)]) // PCB pocket on top
    cube(PCBSize + Clearance + [0,0,Protrusion],center=true);
    if (Channel)
    translate(WireChannelOffset) // opening for wires from bottom side
    cube(WireChannel + [0,0,Protrusion],center=true);
    }
    // Add-on bracket to hold smaller PCB upright at edge
    PCB2Insert = [3.0,4.9,4.1];
    PCB2OC = 45.0;
    if (Layout == "Bracket")
    difference() {
    hull() // frame body block
    for (x=[-1,1]) // bosses around screws
    translate([x*(PCBSize[0]/2 + ScrewOffset),0,0])
    cylinder(r=Washer4_40OD,h=OAHeight,$fn=NumSides);
    for (x=[-1,1]) // frame screw holes
    translate([x*(PCBSize[0]/2 + ScrewOffset),0,-Protrusion])
    rotate(x*180/(2*6))
    PolyCyl(Clear4_40,(OAHeight + 2*Protrusion),6);
    for (x=[-1,1]) // PCB insert holes
    translate([x*PCB2OC/2,(Washer4_40OD + Protrusion),OAHeight/2])
    rotate([90,0,0])
    cylinder(d=PCB2Insert[OD],h=2*(Washer4_40OD + Protrusion),$fn=6);
    }
    view raw Proto Board Holder.scad hosted with ❤ by GitHub