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Parallel Series stuff again ;/

Discussion in 'Electronic Basics' started by Abstract Dissonance, Jan 12, 2006.

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  1. I went ahead and came up with a solution to my problem of trying to switch
    components in all possible series and parallel configurations... a graphic
    of the basic idea is at

    Basicaly I would have a matrix of switches.. each switch though contains 7
    possible ways to connect the 4 wires at a junction(excluding rotational
    symmetry). In the graphic you see the 7 paths and several sample circuits
    that can be generated by using certain paths. I believe I can generate all
    series/parallel combinations with atmost (2n)^2 switches(but may be much
    less. For 2 switches it requires at most 8 junctions to get all 12
    series/parallel combinations.

    My idea was simple to create a switch with all these paths in it and I could
    electronically select the path by some means to to configure the array to
    get any combination I desired.

    The 8th circle is all the "paths" stacked together but each one rotated
    slightly and there would be a non-conductive material between each
    "path"(the grey stuff) which, ofcourse, would be conducting. I figured that
    I could make rotary switch out of this and then rotate the switch with some
    small motor that is controlled ultimately by a MCU so I can select the
    different combinations.

    Another method for the switch would be to stack them all directly on
    top(without the rotation) and be able to select the paths by pushing in and
    out of the shaft... it would require all the "rotational" symmetry to be put
    back in though... 15 or so paths instead of 7.

    I initally was going to do this with relays but it would end up, from what I
    have figured out, to be quite expensive and very bulky. Another thing I
    looked into was a crosspoint switch but I have not been able to determine if
    they can route to all the possible wire combinations and they tend to be
    quite expensive too.

    My requirements is mainly that I can switch from one combination to another
    in < 1 sec at most but I'd be happy with about 0.5s. The switching voltages
    and currents are quite low too but I don't see this as much of a problem
    unless I could miniaturize the switches(which won't happen for a long time

    My main questions are: Is there another method to do this? I mainly need
    relay like action(not solid state stuff but that it could be an option if it
    is cheap).

    The second problem I'm having is trying to actually rotate the switch to
    select the appropriate path. I want this things to be cheap and I'm not
    sure how I can switch the paths easily with a very simple mechanism. I
    guess I'll have to dive into how stepper motors work and see if I can find a
    way to do it effectively and cheaply but any ideas or comments would be
    appreciated on this.

    I have several ideas about how to actually create the "wafers"(the circular
    disks that each contain a path and will be stacked like plates to form the
    switch) but maybe someone can offer an efficient method. My inital idea was
    simply to cut out the paths by hand with some thin copper and place them on
    some cardboard(probably not) or plastic "punches" about 1in in diameter for
    and put a plastic shaft down the center for rotation... this would atleast
    give me a prototype to work with. Another method I thought would be to just
    get some conductive paint and use that to paint on the paths. I could make
    templates for each path and probably even get them to be pretty small(maybe
    even a 1/4in in diameter which would be good enough for me).

    For my project it would require about 144 of these switches and so if I used
    some transistors or relays then the cost would be several hundred
    dollars(from my initial look into it). It would be nice if there was a much
    better way to do this but I can't seem to find anything that is appropriate
    and this is the best thing that I can think of. (My main drive is that I
    cannot alter the original signal to any appreciable degree(which means that
    solid state stuff is most likely going to be out of the question... not
    because it might only affect the single by 1 part in 1M but because of other

    Anyways, Any comments would be appreciated.

  2. ehsjr

    ehsjr Guest

    I think this does almost what you want, for < $25.00
    I haven't figured out, in this circuit, how to do series
    parallel where you have two series strings of 2 parts and
    you want to put the strings in parallel.

    For four components, this circuit uses 4 relays (4PDT),
    and one switch for each relay. (daigramed below)

    If you want to add phase reversal, you need 4 more relays
    (DPDT) and 4 switches. (diagramed below)

    If you want to be able to turn components off, you need
    4 more relays (and the component must be switched to
    parallel). These component on/off relays are not shown
    in the diagrams below - the relay points simply go in
    series with the component leads.

    If you want to place 2 or 3 parts in series and put the combo
    in parallel with the other part(s), you need 1 more relay.

    Parallel bus ----o------o------o------o-------- ==> output

    Parallel bus +---o------o------o------o--------
    serial bus +---o o---o o---o o---o o--- etc ==> output
    1 2 3 4 etc

    A 4PDT relay for each part (component). When the relay is in
    the parallel position, the part's leads are connected to the
    parallel bus pair, and the contact is closed on the serial
    bus for that position. When in the serial position, the
    part's leads are connected to the contacts on the serial
    bus. Example:

    Parallel --------+-------------------------------{{--- ==> out
    o o----------------+
    Ry1-1 ---part--- Ry1-2 |
    Serial +---+---o o---+---serial-- | ---{{--- ==> out
    | | | |
    | | | |
    | +---o o |
    | Ry1-3 ---+-------+--- Ry1-4 |
    | |
    Parallel +----------------------------------+---{{---

    4PDT relay

    Ry1-1 is connected to RY1-3 and to the bottom parallel bus
    rail. No other RYn-1 point is connected to the bottom
    parallel bus rail.

    For phase reversal:

    ---+---+ +---+-----
    | | | |
    | o o |
    | ---Part--- |
    | o o |
    | | | |
    | +------------+
    | |

    For series parallel:

    Parallelbus --------------+--------- ==>Output
    | o----+
    ParallelBus +------------ | --- |
    | o |
    Serial Bus +-------------- |
    o--------+ ==>output


    4 4PDT and 5 DPDT relays and 9 switches
    DCTX-2460 $4.50 * 1 = 4.40 24V dc wall wart
    RLY-464 $1.20 * 9 = 10.80 24V DPDT relay
    RLY-466 $1.00 * 4 = 4.00 24V 4PDT relay
    SSW-37 $0.25 * 13 = 4.00 DPDT slide switch
    Total $23.20

    (Switches are 4 for $1.00)

    The switches can be replaced by your automation circuitry.
    You mentioned that the switching voltages and currents are
    quite low, so you'll need a transistor driver for each
    relay when you automate. You'll need to figure out
    the logic of what relay needs to operate when and sort
    out the signals to drive the transistors. The pesky
    parallel of two series strings bugs me, but it's 2:30 A.M.
    and my brain is in shut down mode. If you figure that
    out, please post it!

  3. Jasen Betts

    Jasen Betts Guest

    ["Followup-To:" header set to sci.electronics.basics.]

    the way I see it for each device a 4PDT and DPDT relay can be used together
    to selest forwards/reverse/isolated/shorted+isolated

    or a DPDT and 2PST to select forwards/reverse/isolated
    (isolated is neither input connected to the device)
    or a DPDT amd SPST to select forwards/reverse/open
    (here open is one of the inputs not connected to the device)

    or SPDT and SPDT to select forwards/reverse/shorted
    (here shorted is both outputs connected to one input)

    a further 4PDT can select series/parallel
    (or you can use a DPDT here if you don't mind the phase of one of the
    devices reversing when you switch from series to parallel)

    anyway 5 relays can do the job. (and thus 5 input signals)

    tyring to manufacture switches can be a really tricky...

  4. colin

    colin Guest

    have you considered a 3 pole 7 way rotary switch ?

    you could easily make the wafer part on a pcb,
    many multimeters have quite complex rotary switches of this type
    if you can see inside one youl get an idea of construction.

    Colin =^.^=
  5. I think the main thing you guys are missing is that I need to build this for
    n components and not just for 2. You can see that even for n = 3 it is a
    much more complex circuit than for n = 2 since one has all kinds of series
    and parallel combinations. Since I will be using around n = 6 or 7 it would
    require many many relays(probably atleast 50+ if not more). The graphic was
    just an example for n = 1 and n = 2... just to get the concept across.

    Although I might be able to accomplish this with the 4PDT relays since ehsjr
    has pointed out that they can be found for ~1$(everywhere I've looked they
    cost atleast 4$ ;/). The problem with the quad relay is that I need it to
    be latching and I'm not sure if its a good idea to have it where I control 4
    switches with one input(what I mean is that it seems for relays that one
    always has to flip all the switches inside the relay together and one can't
    control each switch individually). This seems that it would require a lot
    of thought to all the actual combinations I would end up using(and for n = 6
    it is huge) but I might be able to get it done just using 4PDT relays.

    Another thing is I cannot use solid state or mechanical switches because I
    have to have no degredation of the signal(except during switching it is ok)
    and I cannot have them manually controlled(since that defeats the whole
    purpose of the project... I already have a "prototype" that uses dip
    switches to do most of the combinations).

    So the reasons that I feel I would need to come up with my own method is
    simply that it seems to be cost effective(in the long run atleast) and
    allows the circuit to be easily built and directly to the point of what I'm
    trying to do... and ofcourse that I need a latching type of switch since I
    don't want to waste power to hold the state when I don't have to(hence my
    method can be used with no power except when one wants to switch.... Which
    isn't very often... could be hours or even days without needing to switch).

    Ofcourse this isn't to say that it still can't be done with relays and also
    be cost effective(actually I think the relays tend to be quite expensive
    though compared to my switches since it involes just basicaly punching out
    the paths then stacking them together... except for the motion control which
    might make it more expensive(Still working on how to control the switch
    electromechanically)). I'll look into it some more and see what I can do...

    Thanks for the help,
  6. Can this get all those paths that I need(such as all the "poles" connected
    together) and if so can it be gotten for ~$1?
    My idea was simple to somehow make the layers and then I could easily stack
    them and glue them together then I could worry about the contacts
    later(which I have an idea how to do but I'm not quite sure if it will be

    One could make the conductive paths by punching them out on copper
    sheets(I'd have to make a punch which will be somewhat difficult to do to
    get it accurate I think, but if my switches are large then the accuracy
    decreases... once I get a prototype then ofcourse I can worry about how to
    make it smallter later).. I could use the etching method to generate a lot
    of the paths but I don't have a laster printer to do it... I'd still have to
    place the paths on the wafers with the proper rotation... I might be able to
    do this easy by including a little notch or something to align them up with
    the wafer.

    Once I am able to make the actual switch(which I think would actually be
    pretty easy once I get a good method down) then I'd have to figure out how
    to electromechanically control it. I'm not sure how hard that will be but I
    have several ideas that may or may not work.

    Ofcourse there will be many precision problems and I'll have to work them
    but end the end it might be worth it since it seems to be the only option I
    have that covers all my requirements(atleast at this point in time).

  7. Si Ballenger

    Si Ballenger Guest

    You might want to look at the design of the mechanical switches
    they use to use at the telephone office. They both rotated and
    moved vertically to do the telephone circuit switching. If you
    describe the use for the switching setup somebody may already how
    it has been solved.

  8. What do you mean the use for the switching setup? It is simply to select one
    of the many possible series and parallel combination circuits for n
    components. (n being fixed ofcourse).

    That is all you guys need to know as that is pretty much exactly the
    project... ofcourse there are more details but they will just get in the way
    and for some reason it already seems like a confusing topic... not sure why
    its so difficult to understand what I want to do.

    To explain it again,

    Given N electrical components how can one design a circuit that will allow
    you to realize the components in any wiring(one that make sense of course...
    any way to combine them in combinations of series and parallels(since thats
    the only two ways) to get a new circuit).

    What I mean by a combination is simple a certain, but arbitrary, wiring out
    of one of the many possible ones. e.g., for N = 3 one can have the first
    component in series with the two who are in parallel and all in phase, i.e.

    --> --- ----

    or all can be in parallel


    and the components order does matter... hence

    C1 -->
    --> --- ----

    is distinct from

    C2 -->
    --> --- ----

    which is distinct from

    C2 -->
    --> --- ----

    (where C1's phase has been changed)

    It is simple as that. Now for my specific project I require circuit
    conditions such as:

    1. I can select any one of the combinations electronically(i.e., it cannot
    contain mechanical switches that the "user" has to mechanically push in
    order to get a combination). Actually I will have switches that are
    "presets" that the user can press(and setup) to select a certain
    combination... but they will not have to press more than one switch to get
    at one combination...

    2. The time to change from one combination to another has to be ~ < 0.5s.
    It doesn't have to be "fast" be it can't be "slow".

    3. The switching mechanism cannot degrade the signal except momentarily when
    it switches except by adding a little resistance cause by wires.

    4. Would be nice is the switching mechanism was latching(which means I could
    latch it into a combination so that it will stay there without power being
    supplied... this would reduce power consumptions a great deal I think).

    5. It doesn't have to switch a great deal of voltage or current levels(not
    really a requirement but helps reduce the size).

    6. It should be relatively small. i.e., one can port it.

    7. Should be relatively cheap. For N = 6 it should cost at most 100$ but
    more like $50 or even cheaper like $25(I'm guessing here though).

    8. Ofcourse it should be slightly rugged. It doesn't have to be build like a
    tank but it can't die if, say, bumped or maybe even dropped once or twice.

    and thats about it(I think).

    My first idea was simply to use relays. It solves all the problems except 6
    and 7. Solid state stuff might work well except for 4 and 3.

    The only method, as of yet, seems to be the the method I describe in the
    first post. That is, ofcourse, assuming I can make the switches and control
    them such that 2, 6, 7, and 8 are satisfied. All those issues, I think, are
    easily solved after some tinkering to find the right method to build the
    switches. I do believe the switches themselfs are entirely possible and
    easily to manufacture(and really they will just involve the armature and not
    any type of housing). The hardest part will be to actually electrically
    rotate them and this will be the biggest variable of my project if I decide
    to go with making these switches.

    Maybe that clarifies something ;/

  9. Jasen Betts

    Jasen Betts Guest

    even your 28-way switch will be needed in large numbers to handle all
    series/parallel/polarity combinations for 7 items.

    I don't see that your 28-way switch offers a great improvement over using
    relays, you may find that it's difficult to makke reliable contacts, and
    driving them isn't going to be simple.

    they could easily cost more to manufacture than the equivalent circuit
    builtt using relays.

    ISTM that your 28-way switch could be replaced by 6 SPST relays.
    and apropriate driving hardware.

    by spaciing the contacts unevely it may be possible to use a simpler wiring
    pattern and fewer positions, there are only 15 ways the switch can connect
    the 4 terminals so gives a lower limit.
    a solenoid operated ratchet is what they used in phone exchanges. it might
    be fast enough.

    probably the simplest way to do it for N devices is using 2N N+1 throw
    switches (eg single pole slide or rotory switches) one on each end of
    each device,

    Unless you can find some old telephone exchange equipment (could be hard -
    most of this stuff was recycled 10-20 years ago) _and_ it proves to be
    suitable you'll need to to build these switches and the servos to operate
    it yourself.

    | |
    -o- = connection -+- = no connection
    | |

    a b c d e f gh i j k l m n o

    | | | | | | | | | | | | | |
    1-o---+--+---+--+---+--+---+--+---+--+---+--+---+-- (+) immagine the o's
    | | | | | | | | | | | | | | are connections
    2-+---o--o---+--+---+--+---+--+---+--+---+--+---+-- beween the lines
    | | | | | | | | | | | | | | and can be moved
    3-+---+--+---o--o---+--+---+--+---+--+---+--+---+-- up and down the
    | | | | | | | | | | | | | | columns to alter
    4-+---+--+---+--+---0--0---+--+---+--+---+--+---+-- the way the
    | | | | | | | | | | | | | | devices are
    5-+---+--+---+--+---+--+---o--o---+--+---+--+---+-- interconnected
    | | | | | | | | | | | | | |
    | | | | | | | | | | | | | |
    | | | | | | | | | | | | | |
    8-+---+--+---+--+---+--+---+--+---+--+---+--+---o-- (-)
    | | | | | | | | | | | | | |
    `<A>' `<B>' `<C>' `<D>' `<E>' `<F>' `<G>'

    to reverse the polarity of <A> switch a code to position 2
    and switch b to position 1

    to put <D> and <E> in paralled j goes to 4 and i to 6

    for all devices in parallel

    a b c e d f g h i k l m n o
    1 8 1 8 1 8 1 8 1 8 1 8 1 8


    with this setup the number of actuators needed is 'only' 2n...

    it is be possible to do it with some of switch positions missed
    I'm just not sure what the optimal reduction is. and I don't
    think there are many that can be ommitted.
    i think the maximum reduction is N(N-1)/2 ) switch positions

    If you need a way to islate the devices from the circuit without
    short-circuiting them add another row but don't wire it accross.

    the above (with 7 devices) could be done using 3 relays per column
    (SPST+DPDT+4PDT) for a total of 14 of each type, total 42.

    (you were't far out with your prediction of 50 relays)

    latching relays (which stay switched with no power applied) will
    cost extra, but should offer high reliability ...

    At retail it's probably about (ballpark) $150 worth of relays,
    wholesale or in bulk the price will drop.

  10. yep, but they would probably be very easy to make and only a fraction of the
    number of relays that would be needed(atleast with my initial estimate).
    Well, If say the relays cost 1$+ and I need 4* as many for for each switch
    and I can make the switches relatively easy(which I think I can else I
    wouldn't even bother going down that path) then I think it is a very good
    improvement. After all, I doubt I could make any decent relay that would do
    the job at half the cost I could buy them... but surely this switch has a
    chance. I have some ideas for the contacts though that will make them
    pretty reliable. The biggest issue is making them motorized and of
    alignment. I'm still working on those ideas to see what I can do but if I
    can overcome them then I think its viable... ultimately I think this switch
    handels what atleast 4+ SPST relays can do easily(and thats a low estimate).
    It maybe that one could wire some relay combinations up in an a certain way
    to get the same effect but I doubt it can be done about the same cost as
    using the rotary method.
    I doubt it... except for the motorized part. Think about it a little and
    you will see just how easy and cheap it can be made... after all, I don't
    need a tank of a switch. I could be wrong though but I have a feeling it
    would be must cheaper than going the relay method. If one says that they
    need atleast 4SPST relays to accomplish this(which is the min I think in the
    general case) then thats 4$ for as compared to one switch which might cost
    0.5-1$... or even 2$ if, say, the motorized part costs a lot. It could be
    that to get any reliablity would increase the cost though. I could be
    totally wrong but until I make my first switch(which I hope to get to work
    on soon) I will not know how difficult it will be.
    Its possible, I personally can't see how but thats still approximately
    6$(atleast) for compared to one switch which, I believe, shouldn't cost more
    than $2... Ofcourse I'm excluding the labor costs and some other possible
    issues but I just can't see how it could be more than a few dollars(except
    for the motorized issues... if that can be done cheap then I think the
    switch is a real possiblity).
    Yeah, I thought about that too. I'm not sure what the optimal case is
    though. It was just the best thing I could come up with that easily solved
    the problem. I'm going to have to look at it in more detail though to see
    what if any optimizations can be made. I'm sure that there would be many
    times in the matrix where some switching paths will not be used. It might
    turn out that I would need far less number of relays that the rough estimate
    of n^2*m where m is the number required for one "node".

    I have several ideas to electromechanically control the switch... none of
    which might work. Also, it isn't necessary that I use a rotary method but I
    could also use some type of push-pull method. The switch would be designed
    on the same basic principles though. I'm not sure if it would be easier or
    not to use that but I will probably do some tests to see.

    Well, I feel that it would be a good learning experience. Maybe the outcome
    won't be to my liking but atleast I'll learn something.

    I'm not sure I understand your matrix. if the +'s at the nodes are open
    connections then I can't see how we can get any circuit because there is
    always open nodes everywhere. Although I think I get your drift I'm just
    having some problem understanding your method ;) If it does work and gives
    all combinations I think it would be much easier to implement and cheaper
    and actually not require any relays. I would require some motorized slides
    and 2n total like you said though.




    is just a level that will push on a movable wire like this:

    ---------* *---------

    so one could easily open the "line" by "sliding" to the right position.

    I guess, not sure if that makes to much sense though and I'm not sure if it
    goes with what you mentioned above(and it might be backwhere where you want
    to make a connection instead of break it... but its pretty easy to fix.

    I'll work on it some more. I've been a little under the weather lately and
    its been kinda hard to think ;/

    Thanks for your help,
  11. John Fields

    John Fields Guest


    Do you have a solution which you can post for any number of circuit

    I'm sure... Think about it this way when you get over the weather:

    If you have a number of elements in parallel, you can consider them
    to be connected across a bus which needs to be connected in series
    with the series elements of the circuit. But, if there are no
    parallel elements, then the bus will be open-circuited and, if it's
    in series with the rest of the circuit, you'll get no output.
  12. Jasen Betts

    Jasen Betts Guest

    I ment the straight lines to be continuous conductors that cross but don't
    contact except where indicated by the "o"

    they don't have to be straight sliders they could be 8-way rotory switches

    It might be possible to arrange so that two motors could control a number of
    these switches bay using rotora switches all on the same axle and the axle
    having a bulge with teeth that engage the centre of the switch to turn it.

    it could be tricky switching more that four or five in less than 0.5
    seconds though, so that might not be a good approach,

    a single solenoid could be used to advance the switch around the 8 positions
    it'd need careful design to do it in 0.5 seconds but is certainly possible,
    (I ran an electromecanical counter at 3 times the required rate) an 'index'
    contact would need to be added so the system could reset and get the
    switches into a known configuration.

  13. Si Ballenger

    Si Ballenger Guest

    If you used three dimensions instead of just two, you probably
    could get a lot more circuits and save some space too! ;)
  14. ehsjr

    ehsjr Guest

    Right. And it can get really ugly ... for example, say R1
    has to be in parallel with C1 and C2, and that combo has
    to be in series with R2 - and that combo has to be in
    parallel with another similar setup of R3, C3,C4 and R4
    and so forth. The problem is there are an ever increasing
    number of ways the components can be combined as their
    number increases - something involving N! springs to mind.

    Originally, I thought he wanted this for 4 components.
    Turns out, I missed what he wanted by N-4 :)

  15. ok, I gotcha.
    Can you explain to me how to get say

    | |
    | |---B->---| |---D->---| |
    | | | | | |
    --- A-> -+-+ +------+ +-+- F-> ---
    | | | |
    |---C->---| |---E->---|

    I can't see how to get that with just 'o' being making the horizontal
    conductor contact the vertical one(i.e. a 4way).

    It seems to be that one can't get "sub-parallel" circuits from your matrix
    with just the 'o' I described? Am I missing something?

  16. If you mean arbitrary number then ofcourse not... as one doesn't exist. My
    method works for any arbitrary bux fixed number in such a way that it is
    very easy to do and is cheap(assuming one has the proper components). The
    relay method is also somewhat easy to do but can get expensive really
    quick(which my method might get expensive too if I can't make the components
    cheap enough). i.e. These methods are direct in the sense that they are
    straight forward and scale directly with an increase in the number of
    components. There might be other methods that uses some extravagant
    circuits to get the same result be are more complicated to build. I doubt
    those methods would reduce the cost a half an order of a magnitude than the
    easier methods though. (Ofcourse if they do then there extra complexity
    might be worth it).

    Any easy method that requires N "devices" for N components is simply to use
    ADC's and DAC's. One can then simply create the desired combination through
    software. This is not an option though.
    this bus though only allows for one parallel arrangement? If you look at
    the other post I mention the same problem. i.e., how does it deal with
    "sub-parallel" and "sub-series" circuits? that is, series and parallel
    circuits within series and parallel circuits?

  17. yeah, well, my N is about 6 but can go from 4 to 8 for all pratical
    purposes. It would be nice if I only had to deal with N = 4 ;)
  18. I thought about that but my 3rd dimension was just stacking(or folding) the
    2-D circuit to save space... I'm not sure if I could come up with a true 3D
    circuit that will do what I want (I guess its possible though). It would be
    hard to figure out how to make the switches too ;)

  19. Jasen Betts

    Jasen Betts Guest

    ["Followup-To:" header set to sci.electronics.basics.]

    a b c d e f gh i j k l m n o

    | | | | | | | | | | | | | |
    1-o---+--+---+--+---+--+---+--+---+--+---+--+---+-- (+)
    | | | | | | | | | | | | | |
    | | | | | | | | | | | | | |
    | | | | | | | | | | | | | |
    | | | | | | | | | | | | | |
    | | | | | | | | | | | | | |
    | | | | | | | | | | | | | |
    | | | | | | | | | | | | | |
    8-+---+--+---+--+---+--+---+--+---+--+---0--+---+-- (-)
    | | | | | | | | | | | | | |
    `<A>' `<B>' `<C>' `<D>' `<E>' `<F>' `<G>'

    A from row 1 to row 2
    B and C from row 2 to row 3
    D and e from row 3 to row 4
    F from row 2 to row 4
    F from row 4 to row 8

    The rows represent the nodes (junctions) in the diagram.
    1 and 8 I have chose to be in power connections.

  20. Cool. I believe it will allow for all combinations? If so then it is much
    easier to implement then my original idea by far. I'm not 100% it works for
    all combinations but I do believe it can. The rows seem to "control" the
    "parallel'ness" and the columns the "serial'ness" I'm going to go ahead and
    try and prove it can get all the combinations and if I can do it then I'll
    probably use your idea as it seems much much easier in the sense that I
    don't really have to manufacture much as compared to having to make my own
    switches(which I might do for fun one of these days but I'd rather get my
    project done).

    Thanks for the help,
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