You’ve pretty much described how I felt when, at age 21, I was finally diagnosed with ADHD and realised that a lot of what I thought was down to poor memory, laziness etc. etc. was actually to do with my ADHD.

It is amazing when this kind of thing happens. I guess the tough bit is what to do with the information afterwards. How much to use it to adapt to the lifestyle of others. How much to inform so that others can adapt to your condition. How much to just leave things as they were.

I have a number of friends who are ADHD, Dyslexic, Dyspraxic and Aspergers (as individual conditions not all at once – that’d be nuts!) and I have to say that they are some of the most innovative, interesting and creative people I know. I just wish that Psychiatrists had the knowledge thirty years ago that they do now. It may well have made my school life more rewarding. Perhaps being bullied less, better results (I didn’t do too badly – 7Cs at GCSE isn’t a bad result – but I know with the right help I’d have done better), less accusations of laziness from teachers.

Yes, there are people out there who haven’t seen the movie. And they only get to see it without knowing the ending once. Don’t reduce that number to zero.

As for local properties of my hand, I really don’t know, which is why I would urge people to do their own testing. I was able to observe degradation with one finger, with and without insulating layer. But the message of the post is more to make people aware that the physics is not so simple as “stick something non-conductive in and you’re done”.

In terms of something more practical, I’m taking a leaf out of Anandtech’s book and looking into what sort of tapes are available. Kapton tape that they used is said to have high resistance, and dielectric strength, but their data sheet doesn’t specify dielectric constant, which is what I believe will be the key to a useful tape-solution. I have left a query with their tech support, and will post my findings.

Update: The wikipedia article on Relative permittivity (essentially the same as dielectric constant but measured differently) gives Teflon an impressively low permittivity of 2.1, so that’s certainly where I’ll be looking now

Also, in your own tests there may not have been enough difference between your control (your bare hand) and the different tapes you tried. Are your hands oily/sweaty or very dry? Do you see the signal degrade when you put a finger over the black gap between the two antennae?

And to be honest, I’m not convinced that CR actually did test their theory. They don’t make direct reference to it in the main paragraphs about their testing procedure—which was sketchy at best—they mention it almost as an afterthought, and frankly it looks to me like they were playing for laughs more than offering consumer advice. I could be wrong, but I have asked them to clarify whether the tape was part of their controlled test and had no response.

I stand by the physics and tests (allbethey amateur; I recommend people do their own tests rather rely on mine). And I would add that Apple have now had two great opportunities to go with a protective layer—right now I’d expect them to jump at any opportunity to be seen to be doing something—but clearly don’t think it’s a viable solution. Time may prove me wrong; and if someone knows more about the science, I’d love them to tell me so, since the whole point of the blog is to learn about this stuff.

The issue could be capacitance, true. It could also be a voltage offset between the antennas with the mere conduction of DC voltage between the antennas from perspiration causing an issue for the “failing” circuit. It could even be the direct conductivity messing with the effective antenna length. If it’s either of those than even minimal insulation would provide serious improvement.

Beyond signal strength, this conductivity could explain why some people experience it and others do not. People naturally have different amounts of perspiration with differing salt content.

Consumer Reports may have limited knowledge/ability, but at least they tested their hypothesis. If they found it helped, and others stated it helped, then I can feel just fine in saying it helped.

But seriously, that’s a fair comment also, and on a new blog I appreciate getting any reply. As I re-read, I think I must’ve been a bit tetchy when writing this, and probably felt like laying down the law (s of physics).

So yeah, there should definitely be a clear disclaimer that I might be talking out my hat, and I would genuinely appreciate being shown so; it’s all part of the learning process.

But I’d be careful of outright saying something WILL NOT work before you test it properly.

It hurts your credibility