A crossover clipboard (switchboard) that really works
Anyone who has ever tried to develop a loudspeaker certainly knows the problem of the often necessary change of components in the development diverter. Various solutions This most comfortable, fast and vA. Reliable metrologically in this regard are "in circulation".
In the sound and sound 3 / 2007 has been a switchboard with the cheap speaker terminals. I had ordered a bag full of such terminals. After the inspection of the terminals, I decided not to set up the switch board.
The problem with these terminals was the excessive contact resistance. Then a thin and very soft sheet is pressed onto even softer plastic, and the whole thing with the power of, let's say, household rubber ... How is there supposed to be a joint equal to the solder joint?
Not much better cut for this purpose gladly taken crocodile clips. Contact resistance of ~ 0,3 Ω is not uncommon.
Remains only the reliable, but not exactly comfortable luster terminal, or just about everything soldering ...?
A small linked picture in the Diy hifi Forum but then it still brought me to the funnel ...
The alternative is called Wago, and looks like this:
To understand why these clamps work so well, I recommend the following video:
(Product information from Wago)
So, off to the hardware store (better of course to the local electronics retailer) and 2 packs purchased and glued with hot glue on a piece of pressboard:
The finished crossover clipboard
In this case, an 2 way execution. Red is the plus lead, blue goes to the drivers, black the mass. Time required approx. 20 minutes. Cost ~ 15 €.
The orange levers are clearly on train. There is really tension behind it. If one removes the connected components again one sees that actually a notch in the metal is => If one the same component often one, - and again removed the wire will break off eventually. The best thing is to provide the components with wire and tin the ends. The recordings of the Wagos record everything up to 2,5mm². Whether solid cable or stranded wire.
Even cables that are "permanently" installed should be tinned to prevent any corrosion of the copper.
What else should be mentioned: The board is extremely flexible, and so some application opens up only during use. Just measure a driver? Clack Cable Pull Measuring Plug Clack Finished ...
But now to important part: How do the Wagos beat compared to soldered components?
To find out, I first 6 resistors á 0,15Ohm first in the terminal board in series and then soldered the same resistors and measured both variants.
With quite a surprising result:
The soldered variant has higher contact resistances than the Wago variant (0,002Ohm distributed over 5 connections).
To make sure that no solder joint was faulty, I still measured these individually:
R <= 0,001Ohm. The result was the same for all solder joints.
It is definitely to be assumed that the switch created on the "wagon clipboard" will coincide with the soldered person. In the development of Direct-HA Edition the switchboard came into action for the first time and did exactly what it should do. The measurements of the soldered points were identical to those of the terminal board. Also came to me the idea to build series in some of my points Wagos, eg. for the voltage divider of the tweeter, in order to carry out modifications easily and quickly at any time.