[Milsurplus] A thought on capacitors -

[Bill Cromwell]

On Sat, 2013-02-02 at 08:06 -0800, Mark J. Blair wrote:
> On Feb 1, 2013, at 16:39 , John Hutchins <jphutch60bj at gmail.com> wrote:
> >   The surface mount caps that are now available are there carriers available on the marked to use in wired applications?
> 
> 
> I haven't seen anything made specifically for that purpose. I've occasionally soldered wires onto the ends of surface mount caps while debugging boards in the lab, where I needed to add a capacitance at a node that didn't already have pads on the board. This was just for experimental purposes, and was a matter of doing it "right now" with whatever I had on hand. Otherwise, I would have ordered leaded caps.
> 
> I uses leaded components when repairing equipment that uses them, but all of my new designs (both at work and at play) use surface mount components almost exclusively. At work, I get to do things like cramming an entire GPS receiver into less than 50 mm^2. My hobby designs aren't that sexy, but I still use surface mount components and multi-layer PCBs since that's what I know how to do.
> 
> It would certainly be possible to manufacture tiny PCBs with a pair of surface mount pads for a particular size of capacitor, and a pair of through-hole pads to add wires. You could solder on a cap, solder on a pair of wire leads, and then optionally dip the whole thing in epoxy. I don't see the point, though, as that would be a lot more expensive than just buying a suitable leaded capacitor. Am I missing something?
> 
> 

Hi,

I have some carriers here for SMD integrated circuits and I thought I
saw similar carriers for other parts but it's been a while and I don't
remember seeing them for caps or resistors. I remember one difficult
repair where a circuit board had been burned and needed a cap. A short
distance away the two traces came close together and I soldered an SMD
cap across the gap. That was a field expedient and it worked. I think
the cost of buying carriers like that just so you can use the caps you
have on hand would be penny wise and pound foolish. You can get leaded
parts for that money and not need a carrier card. You will also lose the
miniature footprint.

More recently I have been considering how SMD parts and "dead bug, ugly"
construction might be combined. I need to go shopping for more parts to
investigate that.

73,

Bill  KU8H