One of the many lessons I have learned the hard way from using instrumentation, electronic systems, and cables is simple: tie stuff down and do it well. In other words, use lots of strain relief (or “strange relief,” as my spell-checker says) and tie-downs on cables, and make sure any lightweight instruments are securely fastened to a shelf or bracket (unless they are being used in a handheld mode, of course).
When I didn’t do this, I have had all sorts of aggravating, hard-to-track-down intermittent problems, especially as many of the connectors were inexpensive, non-locking, mass-market consumer models without firm, reliable retaining clips or other retention techniques. Showing respect for “cable management” is a key to consistent, long-term performance and a lesson learned through experience.
I was reminded of this when I was going through some old, defunct electronics I had saved – not sure why – and came across this cable modem which had been totally fried by lighting about ten years ago (Figure 1).
Figure 1 This Motorola cable modem (approximately 10 years old) may look modern, but when you actually connect cables to it (see rear view), it literally falls down on the job. Source: 192.168.1.1
It, in turn, had replaced a slower, obsolete unit, which was housed in a nice, low, plain, very functional rectangular box that stayed in place on the shelf. The cables used with that earlier modem were low to the enclosure back side and thus rested nicely on the surface of the shelf on which the box sat.
But its replacement, the now-zapped modem (a Motorola SurfBoard model SBV5121), seems to have been designed solely to look sexy and cool, and I don’t mean that in the thermal sense. It was a stand-up unit with minimal inherent stability by itself, even without any attached cables. When you actually connected the coax cable, the Ethernet cable, and the dc-adapter cable, it got worse: you had a lot of weight pulling down and across the lightweight box.
Of course, there’s no way it would remain standing up in use. Even if you did get everything balanced just right, any jostling or vibration in the area from the normal flow of the day’s activities in the area was enough to tip it over, especially with the cables attached making it top heavy. Since the cables connected in a vertical row, they were also harder to tie down.
I thought of making some kind of bracket to hold its modem’s base to the shelf, but that didn’t work out. The base had an “artistic” curvature from front to back, plus a V-shaped angle to its footing as it rose up, so you couldn’t hold on properly if you could grab it—which you couldn’t do, anyway, as there was not enough lip width at the base.
Another possibility I considered was to use rugged double-sided foam tape (have you ever used 3M’s 411 Outdoor Mounting Tape with its extra-strong grip?—it’s really handy, even indoors). I would use that to attach the modem to a wide, thin base of wood or plastic for stability and then for attachment to the shelf, if needed. But the bottom of the modem was not a flat surface so the tape would not have enough area to grab. Hold on, this is all getting way too complicated.
There was one semi-satisfactory solution: tie all the cables down in several places, so the modem box stays indirectly supported and thus standing although it is actually floating free, so to speak. That’s what I did, although I regarded it as a “just OK” solution aesthetically and technically. I used self-sticking cable tie bases and cable ties (Figure 2). I like these bases for all sorts of projects since they are self-sticking but also can be screwed down if you want to commit, and they can accept a cable tie in either right-angle orientation, even after they are stuck down in place.
Figure 2 Stick-on cable-tie bases, plus some cable ties, solved the cable management and strain-relief problem of this attractive but impractical modem package. Source: Cable Ties & More
What happened in the design of this basic cable modem, I think, is that the package designer or marketer wanted something that looked sleek, sexy, and trendy. All well and good, but functionality somehow got pushed aside by form. It may look attractive when standing by itself or in a photo, but a cable modem isn’t going to function without those pesky cables attached. Apparently, they were either forgotten or ignored in the design and approval stages.
Admittedly, it isn’t a big problem in the scheme of things; I can manage this issue. But it didn’t have to be any problem at all if the vendor thought about—or cared about—how it would actually be used as much as how it looked in the photos or standing on a shelf by itself. Plus, I suspect many users who don’t think of cable tie bases or similar found it needlessly frustrating.
Have you ever dealt with package design that was at odds with the intended function? Or where you were frustrated by an enclosure design done a certain way for no apparent or useful reason, but which made actual installation and use difficult or unreliable? Have you ever been persuaded by others (such as marketing) to go with a package form factor that you felt was a misguided design?
- Give Me Back My External Wi-Fi Antenna Connector, Please
- Teardown: The DOCSIS 2.0 cable modem falls out of favor
- Giving Connector Contacts Adequate Consideration
- Spade lugs and screw terminals eliminate wiring rat’s nest