27 Jan
2016
27 Jan
'16
10:31 a.m.
On Jan 27, 2016, at 7:48 AM, Ethan Dicks
<ethan.dicks at gmail.com> wrote:
Practically, I would not want to use 60 way connectors and cable. They are
not as easy to get as the 40 way ones.
I just did some pricing and 60-way cable is a touch pricey. Through
cable surplus vendors, I saw one quote of $1.33/ft and from the same
vendor, prices close to $0.30/ft for 28-34-way (you need twice as many
feet, of course, but it's still half the cost. Not a big deal for one
10' run, but trying to cable up 4 RK05s, for example, it would start
to add up). 3x 40-way wouldn't be too bad, if designing from scratch
(I totally get the design goal of a simple double-sided paddle card to
simplify the construction of that - I'm not complaining about Guy's
design, just investigating costs for different methods. For just one
pair of paddle cards and one set of cables, the differences aren't
going to be enough to matter. Wanting/needing multiples for multiple
systems or drives might start to tip the balance).
I just ran some numbers (Digikey*, so YMMV) and here?s what I came
up with:
60 pin connectors (PCB & cable ends): $46.60
4 PCB connectors
8 cable connectors
2 10? 60 conductor cable: $42.12
40 pin connectors (PCB & cable ends): $50.46
6 PCB connectors
12 cable connectors
3 10? 40 conductor cable: $45.30
I believe when I started these, I looked at both. Given that the 60 pin
solution is marginally cheaper (going with new parts which if I?m selling
that?s what I use) and results in fewer connectors (and was simpler to
route).
Note, that *if* I do end up selling the paddle boards, I?ll sell just the
boards and the connectors on the boards. I will *not* be selling the
cable itself (nor the cable connectors).
As you can see from the above, any solution is going to be expensive.
This does not include the boards (since the price for either solution is
the same). I just wanted to illustrate the comparison between 60 and
40 pin cables.
TTFN - Guy
* - I used the same family of connectors for both (from 3M). The only
difference was the total number of pins (60 vs 40). This wasn?t the
most expensive solution either and was pretty close to the cheapest
as I recall but I this is what I?m using for my ?prototype? run and will
probably investigate more fully if/when I do a production run (of course
if folks want just the bare boards they?re free to ?do their own thing?).