Perf vs. Breadboard

[gaussmarkov]

more great stuff!  for a beginner, this is the shared experience of this forum that helps a ton.  so how many tie points do you usually need?  i wonder with a big board (like korgull's 3220 pointer) whether you might work on more than one circuit on a single board?

again, many thanks for all the suggestions above.

[RedHouse]

"Breadboard" or more precisely Proto-Boards are great for banging-up a circuit no doubt, but the down side of Proto-Boards is they have huge stray capacitance issues, all of them.

One can build a circuit and think you have it tweaked-out, but it can often act differently when you finalize it on a PCB or perf-board.

I bolted a big Proto-Board into a cookie tin (12"x12"x3") added I/O jacks, a few holes for pots in the lid, and a cheap stomp switch ('cause they press easy and don't bend the tin can) so when I proto a circuit I can close the lid and try it out while still maintaining shielding.

[DiyFreaque]

"Breadboard" or more precisely Proto-Boards are great for banging-up a circuit no doubt, but the down side of Proto-Boards is they have huge stray capacitance issues, all of them.

My experience has been that stray capacitance can be an issue at times, but for the vast majority of things I've breadboarded and transferred over to protoboard, it hasn't made a difference, at least for the circuits I build.

Having said that, most of my circuits are for synthesizers and are not stompboxes, so there may be a whole side of it I'm not seeing.  Also, I take precautions when soldering the circuit together - I usually put in small value feedback caps on high gain sections to prevent high freq oscillations that mayoccur in the circuit now that it is relatively free of any stray capacitance, on the off chance the circuit liked to have the stray capacitance there so it wouldn't oscillate.  And finally, I use protoboard that has a breadboard type layout, so a lot more arrangement of parts is going to be similar to how it was on the breadboard to begin with.

The only time I recall where stray capacitance gave me fits was when a FET op amp wouldn't work on breadboard, but a bi-polar worked fine (actually Thomas Henry turned me on to what was happening there).  This was in a fairly critical part of a VCO circuit.

There are issues other than stray capacitance that you want to consider as well - sometimes things can work worse once you've soldered it up, particularly if you are using a PCB instead of protoboard or stripboard.

Why?  Because a breadboard with a lot of nice common busses will, to a degree, naturally optimize your power and grounding into a star pattern.  If you don't follow the same philosophy when designing your layout and you end up 'daisy chaining' power and ground more than was on the breadboard, things can get crappy in a hurry.

so how many tie points do you usually need? i wonder with a big board (like korgull's 3220 pointer) whether you might work on more than one circuit on a single board?

It depends a lot on your style.  I like using larger breadboards with lots of tie points, because, yes, you can breadboard more than one circuit, or several sub-circuits, for experimentation on the breadboard.  You can keep the circuits fairly isolated on a single breadboard.  For example, one breadboard I have has a 10 step sequencer and an SSM2164 based VCLPF on it.  Another has an ADSR envelope generator and another CEM based filter on it.  In all cases, the circuits work happily independent of each other (no interaction).

On the flip side of the coin, some people like to get breadboard that's about the size of the protoboard or stripboard that they use so they can easily copy the circuit directly over.

Best regards,
Scott

[DiyFreaque]

Forgot to mention, if not technically correct, and semantics laid aside, the more generally accepted term is "Breadboard".   Calling it anything else serves more to obscure than to clarify.

More often than not, protoboard is in reference to a board that is either wire-wrapped or soldered upon.  Terms for this are also:

Vero, which is a brand name much like Dumpster but is used in a more generic context these days (probably to the chagrin of Vero).  Veroboard was the original stripboard, and often is used in place of stripboard.  But, not all the time.  Some people associate Veroboard with any type of perfboard.

Stripboard, which is a particular layout of protoboard that is used with a spot face cutter or similar tool to form the final trace pattern.

Perfboard, which can have plated holes, or unplated holes for 'flea clip' type connections.  Variations of this is that they can can include particular bus patterns or 'breadboard' type patterns much like stripboard, but do not require a spot face cutter.  Often, when it has this type of pattern, protoboard is used instead of perfboard.

And finally, "protoboard" can refer to none of the above.  Often, boards are designed for specific devices to be used (such as an FPGA or ASIC, etc.) that are also called protoboards, or proto-typing boards.

So, really, 'breadboard' is the one term more often than not unerringly brings a specific item to mind.  Please, I beg of you, don't take this one certainty in life away from me  

Now, what can really get confusing is if someone makes a printed circuit board in a breadboard pattern.  What the heck do you call that?

Cheerio,
Scott

[KORGULL]

so how many tie points do you usually need?

I just barely fit a PT-80 delay on my 840 point Radio Shack board- if that helps give you a rough idea. Any circuit smaller than that was no problem at all.
I wanted a larger board just so I didn't need to concern myself too much with parts placement/layout and to be able to spread things out more so it is easier to see connections and change parts.

[vanhansen]

Here's an interesting question, and I'm sure there will be lots of differing answers.

With your breadboard oriented so the power and ground buses are going left/right (horizontal), which way do you build your circuit?

Left to right
Right to left
Top to bottom jumping the middle separation line between the upper and lower sections
Bottom to top jumping the middle separation line between the upper and lower sections


I've been laying things out right to left so they follow the normal in/out jack order.

[KORGULL]

Mostly left to right. If I start to run out of space anything goes.