Horstmann T50 thermostrat time setting

And another one.  To get to time set you press ‘Select’ and ‘Set’ buttons together for 3 seconds.  Up/down as you would expect, with ‘Select’ to switch from hours to minutes.  Then ‘Set’ to finish

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How to change time on Danfoss TP5000

Just spend 20 minutes trying to find out, and web not helping, so for future travellers … Press ‘Prog’ and the minus button next to it as the same time and you can change the time.

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UK is averagely obese (ish), NOT the second most obese country in Europe

I try not to get to irritated by poor standards in stats in journalism as much as I used to.  Random Daily Mail reports based on flaky sources I can just about get past without more than a few seconds of seeing red (mostly by not looking, I admit).  But, sometimes you hear something from more credible sources that feels surprising enough to want to check whether it really is true.

Over Christmas, I heard reports that the UK was the second most obese country in Europe, behind Turkey.  Whilst I suspect obesity is an issue, and UK average diet is hardly good, I was surprised to hear it was relatively that high.  It also felt fairly hard to measure on a like for like basis, raising the risks of dodgy stats

And, it wasn’t the Daily Mail; I saw it on the BBC ‘what the papers say’ (see here), with reference to the Telegraph (see here).  Though the Daily Mail did cover it too, here.  And the Times here, and the Guardian here.  They all point to an OECD report here, which I would expect to be a pretty solid source. But, reading the source info showed a bit more light.

Page 59 is where the relevant data is graphed (See here).  And, it does clearly show the UK as second highest.  But, it also flags the UK, along with Hungary, Ireland, Luxembourg, Czech republic and Slovak republic as being measured rather than self reported.  5 of these are in the top 6 countries.  And, there is a callout on the previous page noting that  “Estimates from health examinations are generally higher and more reliable than from health interviews”.

What it doesn’t do, which feels pretty naughty, is to give any indication on what correction one should allow for, given that these are effectively two different statistics.  However, there was a review done in Canada in 2008 (see here) that did do both measures, which found that errors in self reporting moved the percentage of those classed as obese from 15% to 23%.  If one had the base information you could probably approximately correct for this in the 6 that were measured, but by good fortune for this purpose, the UK is listed 24.7%, which is pretty close to 23%, so at a first order, one could assume that the UK was roughly 16.5%.  The average will also be overstated by the contribution of these different metrics, but as it stands it is 16.7%.

So, from fag packet maths, I would judge the UK is pretty much average on obesity.  Not that good for an avoidable issue that causes harm, but nothing notable.  Which feels more like what I expected.

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Scottish referendum was a good idea done badly

So, the people have spoken.  Which is a good thing.  Except that it isn’t, or at least not the way it was done.

There seems to be a view that for really big decisions what is needed is a one person one vote decision for that topic – a referendum.  It seems to be held out as a kind of gold standard for good representative decision making, for example demanded and offered for European changes.But, people are bad decision makers, especially when they are not used to seeing that type of problem through and learning from how they turn out.  And the bigger and more unfamiliar the problem the worse they get.  You can see it in the recent financial crisis – lots of hand wringing from many many people, but the ones who were useful were the ones who had got experience in smaller crises.  They weren’t perfect – far from it – but they were much better prepared than those who had no experience of what apparently counter-intuitive moves were required.  When to be tough and when not.

So the problem with Referenda? Its that these are kept for really big decisions, with most smaller decisions taken by representatives elected for the purpose.  For those, you get to see the outcome of the decisions, but there is a huge difference between observing and doing.  It’s like cooking only beans on toast, easting in Pizza Express from time to time and thinking a little bit about how it was made, but then being expected to rustle up a three star Michelin starred  meal for 20.

So, whilst it is really good to see the focus people have made on this vote, and the discussion of various elements, the tough reality is that you just cant go straight to these decisions and judge them well.  Desire and focus is not enough, even if the cat posters would have you believe it is.  And the way the information has been made available to people is just positively unhelpful – from both no and yes sides.  The adversarial system used in courts and politics is a rubbish way to educate people, never mind that they don’t have the experience.

In my mind, a better way would be to vote for representatives to properly consider the topic, spending enough time on it.  Representative democracy in other words.  If it is OK for most decision, why is it not enough for major ones?  In other situations, it is exactly what is asked for, for example a judicially chaired enquiry.

So, whilst I would have voted for Scotland to stay part of the UK, and believe I am moderately well grounded, I know it is only moderate.  And I know many people who did have a vote wouldn’t be that good.  For the future of the UK to be put in the hands of such a poor process is irresponsible.

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Removing the IR lights in a Foscam FI9805W

A year or so ago we bought a CCTV camera for the house, as we seem to have oiks throwing stones at our patio doors every year or so, and we wanted to at least know what they looked like.  We got a Foscam FI9805W which is a high definition, weather resistant, motion detecting WiFi camera that allows us to connect to it from anywhere – and fairly cheap and cheerful, but seemed to have what we needed.  In general, we’ve been happy with it, but it has one really annoying deficiency.  At night, it turns on a bunch Infra Red LEDs, and ta-da, night vision.  The trouble is, that the various bugs and spiders quite like the warm light, and fly/crawl up, and the motion sensing triggers.  Roughly every minute or two, all through the night.

My first thought was to use an external IR light, and one quick ebay later we had one.  But, it turns out if you turn off the IR illuminators on the camera, it turns out it also leaves the IR filter in place in front of the lens, so you see nothing.

A quick web search shows that similar issues with other Foscam cameras.  The IR cut filter is triggered by the IR illumination tuning on, so if you turn it off, the cut filter stays in place.  I can see how it happened – first came the illuminators, then the IR cut filter was added.  But, it’s really annoying.  The web also has some guides on how to bypass the LEDs, but not for this model of camera.  So, for future searchers (yes, this WILL do damage to any warranty!) …

First, remove the sun cover and unscrew the front glass lens cover :-

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Then, remove the four screws holding the illuminator and camera boards into the camera

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Now the illuminator board can be detached – there are four screws, and two cables (one with yellow wires, the other with red) to be removed – watch the cables; the plugs are hard to remove and I suspect that it would be easy to break them.  I had a temporary hope that one of them would be the LEDs, and the other the sensor, and one could just be left unplugged.  No joy.  They both appear to have power and ground, with the yellow one also having an activation line.

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The aim here is to take the LEDs out of circuit, but leave the sensing working.  The LEDs appear to be in 6 parallel sets of 6 series connected diodes with a dropper resistor across the end of each. Tracing the circuit is a pain as its a multi-layer PCB.  The dropper resistors are easy to find as they are just the 6 biggest ones.  In the picture below, they are labelled R3 and R7 on the left hand side half way up, and R17, R18, R5, R2 on the right hand side running from half way down downwards.  They all need to be taken off – not too tricky with fine nose pliers and some care with a fine soldering iron.  Keep them if you ever might want to reverse the process.

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I did hope this would e enough, but it wasn’t quite.   The trigger is now floating unconnected unless activated, and needed to be tied to the power line.  So, I added a 220k ohm resistor from between the +Ve rail and the old resistor feed.  there is no easy way to find the +Ve line, so I traced through a set of the LEDs until I found the end of a chain of 6, that was a sensible distance from one of the resistor feeds.  If you find the same board as me, you can see this below.  Note that the upper lead of the resistor is soldered to the lower of the pads for the resistor, even though the photo makes it look like it is the upper one.

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In customary fashion, reassembly is the reverse of the above.  And … it works exactly as desired.  The IR control now affects only the IR cut filter. 

If you wanted to be able to switch this all back to the way it started, you could put a waterproof switch on the back of the case, switching a replacement dropper resistor in and out – the pull-up resistor could be just left.  But, I can’t think why I would want more video of flying insects & spiders!

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