Aldi bargain laser level

[andrew lynerParticipant @andrewlyner71257]

Posted by RMA on 14/07/2019 08:38:09:

Thanks for the pointers folks, but I'm assuming most of us on here are beyond a certain age and don't use trendy 'language' obviously found to be necessary by the younger population. I certainly don't intend to learn it now, I'll just ignore the posts that contain it! There must be better ways to recapture your youth, another topic maybe for the tea room?

Apologies for going off topic.

That's a shame. Language is a fluid thing and, by ignoring the recent additions, you can miss out on a lot of useful stuff. If TTFN and ITMA mean something to you, then you were part of the new wave of acronyms in the past. Stay in touch; you won't regret it.

[Nicholas FarrParticipant @nicholasfarr14254]

Hi, here's one for the level in question. NMFP It's not what you're thinking.

Answer; Not Meant For Precision, although there is a more well known answer in some of the work places that I've been into.

Regards Nick.

[RMAParticipant @rma]

Posted by andrew lyner on 14/07/2019 10:41:37:

Posted by RMA on 14/07/2019 08:38:09:

Thanks for the pointers folks, but I'm assuming most of us on here are beyond a certain age and don't use trendy 'language' obviously found to be necessary by the younger population. I certainly don't intend to learn it now, I'll just ignore the posts that contain it! There must be better ways to recapture your youth, another topic maybe for the tea room?

Apologies for going off topic.

That's a shame. Language is a fluid thing and, by ignoring the recent additions, you can miss out on a lot of useful stuff. If TTFN and ITMA mean something to you, then you were part of the new wave of acronyms in the past. Stay in touch; you won't regret it.

Sorry, I don't regard this as language in the true sense, and if you have to resort to looking up these stupid things on Google, I won't bother. It's just laziness if you only include it once, but I can see the advantage if you're having to repeat it several times so long as it's explained at the beginning!

The correct thing to do is to put the meaning in brackets following the acronym so everyone knows what you're on about. Language is all about communication, not research.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by RMA on 14/07/2019 21:25:34:

The correct thing to do is to put the meaning in brackets following the acronym so everyone knows what you're on about. Language is all about communication, not research.

.

In principle, I agree … but unfortunately, quite a few of these common acronyms contain words which would not [or perhaps should not] be considered appropriate on a 'family friendly' forum.

MichaelG.

[andrew lynerParticipant @andrewlyner71257]

I'd be interested to know the age at which these things cease to have validity for an individual. I have a feeling that I am by no means the youngest member here and I wonder if it's I who am out of step. I certainly qualify as a grumpy old man.

Does acronymophobia kick in when the free TV licence does? Does it kick in at State Pension time – or perhaps when policeman start looking younger?

Language is a tool and we all like to use new tools if they do the job.

[Neil WyattModerator @neilwyatt]

But what does RMA stand for? return Merchandise Authorisation?

I'm sure (most) younger readers will struggle as much to know what Dumpy and Cowley levels are*.

Neil

*Actually don't assume any knowledge of such things fr people of any age, I recently saw a clip from the Onedin Line where the skipper found his position using a theodolite. On its side. Under solid cloud.**

**I suppose, at a push, he could have been using it to measure the angular separation of two landmarks, although they appeared far out to sea and there was no evidence of him doing any trig.

Edited By Neil Wyatt on 15/07/2019 01:16:20

[Sam Longley 1Participant @samlongley1]

Posted by Neil Wyatt on 15/07/2019 01:13:37:

 

I'm sure (most) younger readers will struggle as much to know what Dumpy and Cowley levels are*.

Neil

Of course they are antiques now & consigned to the bin.(mine is not, I used it last year) But when Paul used a laser to align his fence & drains he could possibly have used a set of boning rods to far greater effect.

My grandfather was using water levels as did his grandfather before him & mine is hanging in the shed. But ask someone how to fill one (they do not work if they have air bubbles in them) — there is another question for you

But should they assume that because it is a " laser" the instrument supplied is adjusted for accuracy in the first place? & just because it is modern it does not always make it the best tool for the job

Edited By Sam Longley 1 on 15/07/2019 07:38:49

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Sam Longley 1 on 15/07/2019 07:29:28:

But should they assume that because it is a " laser" the instrument supplied is adjusted for accuracy in the first place?

.

Certainly not, Sam

But what they can reasonably assume is that [to within 'engineering' standards] the beam is massless and straight … which is a very good start.

The beam will not be particularly well shaped, and will be divergent; but there are 'work-arounds' for these failings.

MichaelG.

[Sam Longley 1Participant @samlongley1]

But a laser level, which is a very common use for them, could be pointing up in the air (or down)

 

Edited By Sam Longley 1 on 15/07/2019 08:05:45

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Sam Longley 1 on 15/07/2019 08:03:15:

But a laser level, which is a very common use for them, could be pointing up in the air (or down)

.

Yes of course it could, Sam … That was the point of my first few [emboldened] words !

As with so many cheap modern products, there is something useful inside … which probably has 'negative value added' tat surrounding it.

Consider the potential: A laser module probably costs less than a length of bricklayer's string.

MichaelG.

[Blue HeelerParticipant @blueheeler]

A dictionary is just as useful today as it was 50-100 years ago.

**LINK**

[RobCoxParticipant @robcox]

Concerning the use of acronyms, we had a case at work where one of my colleagues complained to a customer that their documentation contained too many TLAs that they hadn't defined. Their response was "what's a TLA?".

QED

Rob

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Blue Heeler on 15/07/2019 08:48:36:

A dictionary is just as useful today as it was 50-100 years ago.

.

I take your point, but:

Personally, I lost faith in 'the dictionary' when they updated the definition of the word "literally" to include the informal usage.

I remain a [platonic] lover of old dictionaries.

MichaelG.

[Russell EberhardtParticipant @russelleberhardt48058]

Posted by RMA on 14/07/2019 07:30:22:

I wish posters would refrain from including a group of capital letters in their post which mean absolutely nothing to me! Am I the only one that doesn't understand these things. I'm assuming it's 'text speak', but this isn't texting is it?

I don't think it is "text speak". If I remember rightly many of these abbreviations started in the early days of Usenet discussion groups. The use of abbreviations helped when you were using a modem that operated at 1200 b/s downstream and 75 b/s upstream or even a 300 b/s audio coupler. Those were the days

Russell

[SillyOldDufferModerator @sillyoldduffer]

Posted by Russell Eberhardt on 15/07/2019 09:41:44:

Posted by RMA on 14/07/2019 07:30:22:

I wish posters would refrain from including a group of capital letters in their post which mean absolutely nothing to me! Am I the only one that doesn't understand these things. I'm assuming it's 'text speak', but this isn't texting is it?

I don't think it is "text speak". If I remember rightly many of these abbreviations started in the early days of Usenet discussion groups. The use of abbreviations helped when you were using a modem that operated at 1200 b/s downstream and 75 b/s upstream or even a 300 b/s audio coupler. Those were the days

Russell

Mention of 300 baud modems reminded me of a gross example from my guilty past. We did it as a joke, but my career in computing included a time where we would use ASCII control codes in normal conversation. For example:

Question. Fancy a coffee?
Answer. NAK, NAK, NAK

In American Standard Code for Information Interchange (ASCII), Hexadecimal 15 is the control code for 'Negative Acknowledge'. Only elite members of the inner sanctum know that!

For reasons not understood by us young nerds, management were displeased when customers complained. Quite hard for chaps who fought at Alamein asking if their job was finished to be told 'NAK NAK NAK' by a spotty long-haired youth with a failed Zapata moustache, loon pants, psychedelic nylon shirt, and a smelly Afghan coat.

Dave

[Neil WyattModerator @neilwyatt]

I posted this in the 'Aircraft Radio Scanner' thread – with my tongue in my cheek

I got a USB (Universal Serial Bus) SDR (software defined radio) for my laptop PC (personal computer). It cost about 16UKP (United Kingdom Pounds). I use it for meteor detection using RADAR (Radio Detection And Ranging) scatter with free software, but it will pick up almost anything you can make an aerial for, and you can switch it between FM (Frequency modulation), AM (amplitude modulation), USB (upper side band) and LSB (lower side band) or even stereo FM.

As SOD (Silly Old Duffer) says, this is a really cheap and easy way to experiment.

Neil

[Frank GorseParticipant @frankgorse]

Neil,that sounds like a pelorus,a simple horizontal protractor with a sight that is probably still fitted on ships today. Anything which relies on a spirit level is of limited use at sea but the horizontal angle between two known points will give you ‘distance off’,add a third point and you have a position fix. The same thing can be done with a sextant used on its side. No trig required,just a couple of lines on the chart but as you say you do need to be able to see the coast.

[Sam Longley 1Participant @samlongley1]

A Horizontal angle on its own will not give you distance off because it will subtend an arc which could be any distance from the shore dependent on the length of either leg. You need a compass to determine the direction of the legs. In which case the sextant is not required. Without the compass bearing you would not know where to draw the lines.

However, Charts show the height of light houses which gives the third dimension of your triangle for distance off if you take the angle vertically. You need to be able to see the base & know the height of tide then you can calculate the distance to the object That is unless you know the dipping distance, in which case the vertical angle is irrelevant. But you still need to know the bearing from the light to get a position fix within a reasonable estimate.

The "dipping distance" is the distance at which the light appears to drop below the horizon.Add to that, the dipping distance of the observers eye above the waterline & you have an approx distance off.

Better still if you have GPS & it is not being jammed

Edited By Sam Longley 1 on 15/07/2019 16:47:42

[andrew lynerParticipant @andrewlyner71257]

There are sooo many clever old fashioned tricks to navigating near the coast. I must say that I tended to be a bit sloppy about doing it 'properly' when there are three GPS receivers on board. Natch, to get a useful course over ground will always involve adding some nowse about tidal streams; a 'simple' chart plotter can take you very much the long way round on long passages.

I did my first coastal Nav course about fifty years ago and we had to do everything the conventional ways. GPS has its problems though. Whereas you were lucky to rendezvous with another boat in the old days, you stand a significant risk of bumping into it if you both have the same destination co-ordinates punched in.

[Frank GorseParticipant @frankgorse]

Quite right.one horizontal angle needs a compass bearing to give position. Two horizontal sextant angles on three objects gives a fix where the two arcs overlap and both were still in the textbooks for RYA yachtmaster not that long ago but I’ve never tried either.and shouldn’t want to have to when it really mattered.

There used to be tables of ‘dipping distances’ in Reeds (along with useful things like emergency childbirth) and I still have a copy somewhere.

Fully agree about GPS though!

[Sam Longley 1Participant @samlongley1]

My first "foreign trip" from Burnham on Crouch to Ostend was in 1969 & I missed Ostend by 9 miles (no lessons for me) I hadn't a clue where I was.

I have just returned from 6 weeks single handed cruise to the Channel islands (picking up the June 06 D day landings on the way) & just as I left, my chart plotter failed. The best part of the trip was having to manage the navigation conventionally. Especially 2 legs of approx 100 miles – part over night,out of sight of land-, wondering where on earth I would end up. The rocks around Channel Islands tend to focus the mind .

Spot on every time- So what I learned all those years ago still worked.

Edited By Sam Longley 1 on 15/07/2019 19:07:07

[Sam Longley 1Participant @samlongley1]

Posted by Frank Gorse on 15/07/2019 18:56:03:

Quite right.one horizontal angle needs a compass bearing to give position. Two horizontal sextant angles on three objects gives a fix where the two arcs overlap and both were still in the textbooks for RYA yachtmaster not that long ago but I’ve never tried either.and shouldn’t want to have to when it really mattered.

 

With the greatest respect, Are you sure about that?

Somehow I do not think that would give a reliable fix.The RYA method uses 3 compass bearings not a sextant angle If one has a sextant one has to work from a point towards the targets

One would have to lay the compass bearing line first then set the angle with a protractor or similar tool & slide it along the bearing line until it met the target. Repeat for the third point. The whole fix would be totally reliant on the first bearing, thus making the fix very unreliable. If one had a compass to take the bearing in the first place then one would continue to take bearings.

If you think about it, there is no advantage in using a sextant which is not only difficult but would produce an inconsistent fix.

Edited By Sam Longley 1 on 15/07/2019 19:27:30

[andrew lynerParticipant @andrewlyner71257]

The RYA method uses 3 compass bearings not a sextant angle

If you have ever tried to take a fix with a hand bearing compass then you would realise the accuracy (on a rocking boat) is +/- several degrees (yes really). A Sextant angle can be measured to much less than a degree with practice. That's because you move the wheel until the two images are superimpiosed. So HSA is a very powerful tool.

I can't remember the geometry involved in using that angle to help with a fix but it's a pretty damned good method. iirc. What you see in a hand bearing compass will just NOT STAND STILL!

RYA don't expect an inshore yatchsmperson to own a sextant as everyone thinks they are for blue water trips.

Edited By andrew lyner on 15/07/2019 19:47:06

[Sam Longley 1Participant @samlongley1]

I would back the accuracy of my Sestral Handbearing compass aimed at a single point up against my sextant held horizontally, whilst trying to fix on 2 points any day.

[Ian Johnson 1Participant @ianjohnson1]

Posted by Clive Hartland on 14/07/2019 08:29:02:

Standard Instrument securing thread in the UK is 5/8" x 11 Tpi. Whit. form. There is another US style at 11/16 " x 11 Tpi. This is mainly used in Aircraft building, test equipment.. Also some military applications, just to be awkward I think.

I give up! I'm going to make my own standards! I had a quick Google for 5/8" to 1/4" adaptors and got loads of 5/8" x 27 tpi for microphones, but I'll still stick with my theory that 5/8" x UNC is a standard for surveying stuff , in the UK at least!

And as for acronyms, two common ones when I was on the tools were 'US' (Un-serviceable) and 'MT' (empty) usually written in chalk.

Ian

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