Model Boat Mayhem
Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: flag-d on April 15, 2006, 10:51:48 pm
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I have a WWII MTB and was going to fit 'grain of wheat' type bulbs for lighting (nav, mast-head, stern etc) but have 'blown' a couple of bulbs already (or they were dead in the pack). Been wondering about using mini-LED's instead. Anyone know if they're available complete with resistor as a ready to use package, as it were? I have a Tamiya truck model which is loaded with the things.
Mike
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LED's without a resistor usually drop 1.9 volts when conducting at their normal rating of 10 - 20 mA. I don't know if sub-min ones are available with a built-in resistor, but if they are, they will probably be identified by having a rather higher voltage rating.
You do see ordinary ones being used without a resistor (like the key ring lights), which have a 3 volt supply, but these rely on the internal resistance of the battery to limit the current.
If you try running one without a limiter from a source capable of high current, it will glow very brightly, very briefly, once. You don't have to let the smoke out of electronic bits for them to stop working, just re-arranging it internally is enough.
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Mike - there was a thread on the old forums that dealt with this, which is unfortunately lost now, but I did manage to save off a couple of the links before it went.
LED Information and Resistor Calculator (http://www.rc-cam.com/led_info.htm)
Article about using LEDs in Model Boats on RCGroups.com (http://www.rcgroups.com/forums/showthread.php?t=419960)
Another article on LEDs from the Model Electronic Railway Group website (http://www.merg.org.uk/led/)
I've been experimenting with LEDs and found the following ebay supplier very helpful and reliable.
Goodwill LEDs Sales (http://stores.ebay.co.uk/Goodwill-Leds-Sales_W0QQssPageNameZstrkQ3amefsQ3amesstQQtZkm)
I've found that the narrow viewing angle LEDs can be used very effectively if they're encased in some form of translucent lens. I use acrylic beads (available in red/green/amber/clear and most other colours) that I turn down in the lathe, drill out for 3mm LEDs and place a brass cap on top. The brass cap reflects the light down the edges of the lens giving an all-round light.
Hope this is of some use :)
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www.ultraleds.co.uk has some usefull info
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The biggest problem with using LEDs is that they are not as bright in all directions as a 'bulb' type light. There are 'tricks' to make them brighter in some directions, but, unless you're a lens grinder it may not be the easiest thing to do.
Figuring the size of the required resistor isn't difficult once you get your mind wrapped around how it works, simple math. 'Course, the 'wrapping' part isn't all that simple at times because of all the different ways of stringing them together. (All those 'electronics' guys are a bit 'twisted' anyway, right?)
The good part about using LEDs is that they are almost indestructable, meaning that you don't normally have to provide access paths to them. They are also not as fragile as other 'lights' One of the really 'neat' things about LEDs is that you can make them change color. Not too sure how often that would be required, but it sure opens some possibilities!
- 'Doc
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Thanks all! Wow! Rapid response and plenty of good info too. Thanks again. Looking again at the electronics 'black box' of my Tamiya truck, I see that there is a host of resisitors fitted immediately before the connection pins: so the LED's dont have built in resistors after all!
Thanks again
Mike
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Hi
I got these 2 pages off the old MB site, I can't remember who placed them on but they may help you
http://www.kpsec.freeuk.com/components/led.htm
http://metku.net/index.html?sect=view&n=1&path=mods/ledcalc/index_eng#series
riggers
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Hi Mike..
I think one of the main problems is that the LED radiates the majority of its light out through the dome on the top. I'm not sure if the sides can be polished but would be very interested to see if it could be done.
Hmm!!. Might just have a look at that.
If the wheat bulbs are blowing, could it be that you may be supplying too much power to them?
Just a though.
Declan
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The biggest problem with using LEDs is that they are not as bright in all directions as a 'bulb' type light.? There are 'tricks' to make them brighter in some directions, but, unless you're a lens grinder it may not be the easiest thing to do.
Figuring the size of the required resistor isn't difficult once you get your mind wrapped around how it works, simple math.? 'Course, the 'wrapping' part isn't all that simple at times because of all the different ways of stringing them together.? (All those 'electronics' guys are a bit 'twisted' anyway, right?)?
The good part about using LEDs is that they are almost indestructable, meaning that you don't normally have to provide access paths to them.? They are also not as fragile as other 'lights'? One of the really 'neat' things about LEDs is that you can make them change color.? Not too sure how often that would be required, but it sure opens some possibilities!
- 'Doc
Hi Doc - Of course us electronics guys are twisted - it's all that lead in the solder.
The LED's that change colour usually do so by being a pair (or more of LED's in one package, some have one common connection and one for each colour, in which case its just a question of adjusting the current for each element to get the required colour mix, either by simple resistor selection or by doing some pulse width modulation.
Those that are red/green and just have two connections have two elements, one green, one red, that are connected in reverse parrallel. This means that if the supply is connected one way, the red element works, reverse it and the green glows.
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malcolm,
And if you're really bored, try cutting the 'top' off of a metal cased transistor. Apply small currents and watch the junction light up... (Not a joke. Transistor junctions are basically (sort of) the same as an LED junction and they do light up. 'Course, if you're ~that~ bored, go take a nap.)
- 'Doc
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Hi
I'm a new kid on the block but I have some info on LEDs for lighting. I have used LEDs on a recent model tug and a lifeboat. As regards brightness, veiwed from the side they are as bright if not brighter than GoW bulbs. The are available to take various voltages. www.maplin.co.uk can supply a range of colours including red and green leds in 3, 6, 12 volts 3mm, 5mm or 8mm. and they start from around 14p each. Coloured LEDs are quite cheap it's the clear ones that are relatively expensive starting at around a ?1.00 each. They can even supply flashing LEDs. I use bulb holders from Mobile marine Models which are machine to take either 3mm GoW or LED or a larger size to take 5mm LEDs. For clear LEDs a resistor needs to be fitted in the circuit to drop the voltage.
if you want further info let me know.
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I have an R.A.F. Crash Tender and it uses L.E.D.'s for lighting. I am using a voltage regulator to keep the voltage at approximatly 3v. This means if your running a motor off the same battery it will reduce the volt drop on the L.E.D.'s so they will remain a constant brightness. Another advantage of this system is that you can add as many lights as you want by linking them in parrallel. For those who may use different voltage batteries you will not notice any difference in brightness as you would with just resistors.
For clear LEDs a resistor needs to be fitted in the circuit to drop the voltage.
It is not only the clear L.E.D.'s but all L.E.D.'s will need to be dropped in voltage to approximatly 3v.
I have made a webpage up for those who may be interested in building their own voltage regulator.
See:- http://www.modelfireboats.co.nr/ue/byoc/reg.html
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Just disasembled a birthday card, the one that plays a tune and flashes lights at you,
What a wonderful idea for a disco in the main cabin of the next boat,
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I've just lit my tug with LED's. Used a 5v regulator so I can power them from the 7.2 boat pack or from a 9v battery. I filed down the tops of the LED's, then painted the 'back' and 'sides' of the mast head light, nav lights etc, white, to reflect light back in, then black, to look right. They work well, I have a 'distribution board' that has three fixed resistors and one pot to get the light levels right between amber deck lights, white floods for the towing deck, and the running lights. The Mk II version now being built has four variable pots.l'll also add in some miniature switches for each bank of lights, and add on extra towing and stern lights.
Andy
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I've just lit my tug with LED's. Used a 5v regulator so I can power them from the 7.2 boat pack or from a 9v battery. I filed down the tops of the LED's, then painted the 'back' and 'sides' of the mast head light, nav lights etc, white, to reflect light back in, then black, to look right. They work well, I have a 'distribution board' that has three fixed resistors and one pot to get the light levels right between amber deck lights, white floods for the towing deck, and the running lights. The Mk II version now being built has four variable pots.l'll also add in some miniature switches for each bank of lights, and add on extra towing and stern lights.
Andy
I am about to do something similar.
could you post a circuit diagram, or PM me with details please
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If you need brighter lights use the higher candle power leds, I bought some and they are rated at 18,000 candle power, when turned on through the day they can still be seen even on a bright sunny day. I also have a battery pack attached under the superstructure so that the lid can come of without disconnecting wires...
Roy
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LED's with a wide viewing angle are available.
For instance, there is the 'Golden Dragon' range of LED's by Osram. These give off high luminance at a 120 degree angle- very close to a conventional tungsten lamp, but much more efficient.
They achieve this by incorporating a built in reflector. However, they are rather expensive and probably a little too bright for most model applications.
Another LED range is the S-flux LED's. These have a radiation pattern of 45 degree, which although less than Golden Dragon, is still much better than most LED's.
These are used on a lot of up market cars (i.e. 3 series BMW) for rear lights, and indicators.
I purchase LED's from these guys-
http://www.lsdiodes.com/shop/index.php?main_page=index&cPath=4
Excellent service, low prices and cheap postage.
Andy
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Maplins' catalogue is a mine of info (especially for the uninitiated) on the use and fitting of electronic components incl. LED's. Maplins also supply LED covers in clear/red/green/yellow which with a bit of careful masking & painting can become realistic navlight housings if working in a suitable scale. Try www.maplin.co.uk
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With using leds what about if you want to use them as flood lights, any suggestions as what to use for a shade directing the lights onto the deck...
Roy
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Roy,
There's no significant heat output and so you can use whatever you like.
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I'd agree with that, but with a caution.
LED's do give off heat, and the very powerful ones significantly so, to the point of needing some form of heatsink.
However for most modelling purposes, you won't require very powerful LED's, so what Barry says is largely correct.
Andy
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So if you are having down lights you have to make the shade as they are not readily available...
Roy
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I don't understand what you mean by a 'shade'.
Andy
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So if you are having down lights you have to make the shade as they are not readily available...
Roy,]
Assume you mean a decklight housing or similar deflecting light downwards? As mentioned earlier you can get LED covers which may be modified to become lamp housings. However, given the size of most LED, I would not be surprised if a light housing sold as a model fitting could not be modified. Just a matter of searching.
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In which part of north London dont they have lamp shades then ? ;D ;D
Richard
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Here's the diagram for the power supply system for my tug. 9V comes from a PP3, though I could have used the 7.2V from the battery pack, if I'd felt like drilling through the watertight deck hatch! The 5V from the regulator then goes through 4 pots, all set to give different levels of brightness.
(http://i30.photobucket.com/albums/c334/andygilbert/ledpowersystem.jpg)
Andy G
You can see the diagram a bit better at http://i30.photobucket.com/albums/c334/andygilbert/ledpowersystem.jpg
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Maybe a light shade is the wrong choice of words, what about reflector for a standard lamp. that type of thing, are these available or do you have to make your own..
Roy
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Speaking of LED's anyone got an idea how to defuse led so they give off a more incandescent glow?
I want to put an led in 2 mast head oil lamps on Jan's Puffer but want them to give off a glow....
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MARTIN,
If you want them to be duller, paint the globe with the same colour paint then you will only get a glow not a bright light....
Roy
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Use a fine file on the led, so that the surface is no longer smooth. File off the top and paint the sides that won't show, as detailed in my earlier post. Then adjust the power going to them with a resistor or pot [see diagram]. My nav lights glow but the others are brighter.
Andy G
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Speaking of LED's anyone got an idea how to defuse led so they give off a more incandescent glow?
I want to put an led in 2 mast head oil lamps on Jan's Puffer but want them to give off a glow....
LED's tend to give off a rather cold blue or greenish white light, compared with a tungsten filament lamp.
However there are now 'Warm white' LED's available, which mimic conventional lamps. They are more expensive, but will look more authentic in your case. The other alternative is to paint the LED with a thin coat of translucent yellow paint.
http://www.theledlight.com/5mmwhleds.html
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i have used suppliers listed on www.ledlight.co.uk, some great stuff on there..... the great thing is white LED's when potted in clear resin work so well underwater on my submersible.....
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Anybody
Before commit myself to a pile of smoke ::),
Could someone check my circuit for me (see below), as I don't know what I am doing.
I want to try and do things with circuits in series as it simplifies the wiring and would make it neater as I will have wiring going up one mast, along the triasic stay and down the other mast. It will also allow me to hide a single strand of wire below the rail.
I have used the calculator given in a previous link to work out the resistance needed, but I am worried that the currents may be too low.
Would I be better of with a small variable resistor, if such a beast exists ???
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That won't work.
You musn't feed different voltage LED's in series. Group the voltages together and feed them in parallel legs.
Andy
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That won't work.
You musn't feed different voltage LED's in series. Group the voltages together and feed them in parallel legs.
Andy
Why is this? I am trying to understand and learn. ::)
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Read and digest-
http://www.lsdiodes.com/shop/index.php?main_page=page_4&zenid=4104721b49f9174cf66281956e152be4
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The primary reason not to feed different voltage devices in series is that there is the chance of the max voltage of one device being exceded. That doesn't mean that you can't, just that you should take care in doing so. It also means that the higher voltage device won't give full output, but that's your reason for doing it, right? The 'other' problem with series fed devices is that if one goes out (burns up) all the others go out too (series fed Christmas lights? Finding the 'bad' device is such fun!) Still doesn't mean that you can't do it. I favor parallel feeds when at all possible... cuz I'm lazy.
- 'Doc
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tigertiger, your circuit will work since all the "voltages are per LED" are below their maximum accepted voltage however you will find that those rated at 3v will be dimmer than those at 2v. ::)
I agree with "Subculture" in that you should group the LED's together, I have attached the circuit below if you are going to use that method, this should light the LED's up at their full capacity.
If you go with "Doc"s method of wiring them in parallel I am more than happy to come up with a circuit for that too. ;)
Hope this helps! ;D
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T-tiger,
Going on that the assumption that you've heeded Doc and Subculture's advice, then it's a safe bet thet you're pretty up on LED theory by now.
For what it's worth, here's a tried and trusted method of resistor calculation...
1) Assume Red and Green LEDs to have a forward voltage drop of 2-volts. In simple terms, this means a red or green LED would need at least 2-volts in order for it to glow.
2) Assume White and Blue LEDs to have a forward voltage drop of 3.5-volts to 4-volts.
3) All LEDs will glow with a current (not voltage) of between 10mA and 50mA.
4) Do not connect the LED without its current-limiting resistor (it's bound to blow, else).
5) Do not shove more that 50mA up there.
6) As you might know by now, never mix differing-voltage LEDs in series.
While re-drawing your original circuit I noticed that you're running from an 18-volt supply. So in case you're wondering how I arrived at the resistance values shown, or if you find yourself needing to run from a supply other than 18-volts, here's how...
First of all, ascertain the LED forward voltage, then deduct this number from your supply voltage. i.e: let's assume you're using a white LED. This means you have to deduct 4-volts from 18-volts to arrive at 14-volts.
Next, decide on the needed current. 10mA would yield a less-bright LED than if you were pumping, say, 50mA through it. But bear in mind that the higher brightness will mean more drain on your battery supply. A good trade-off is a current of around 20mA.
So now you've decided on the LED, and the the amount of current flowing thru it, you need to ascertain the resistance value.
Simply divide 14 volts (your battery voltage minus the LED forward voltage drop), by 0.02Amps (20mA). The answer is 700 ohms. But since 700-ohms is a non-standard value, round the number off to the next nearest value... in this, it's 680 ohms.
It's easier to do the math than it is to explain.
Hope it's of some help.
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...The 'other' problem with series fed devices is that if one goes out (burns up) all the others go out too....
- 'Doc
I was lead to belive that LEDs (unless over driven) have extremely long lives, and it is unlikely they will burn out.
Is this incorrect?
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Read and digest-
http://www.lsdiodes.com/shop/index.php?main_page=page_4&zenid=4104721b49f9174cf66281956e152be4
Thanks for the link subculture.
Looking at it, I think I can mix voltages.
If wired in parralel I need to use resitors to balance the voltage.
If wired in series it may not be a problem, as I will get lower light emmision from the higher voltage LEDs (as suggested by Fireboat).
But there does seem to be a difference of opinions on the use of differrent voltages in Series.
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Firstly thanks for all the advice so far guys. ;D
Secondly,
Sorry for three posts in succession, but I thnk one subject, one post, helps clarity.
And there is more than one discussion. 8)
Third,
Slight change of direction here
I am unclear :-[, from diagrams I have seen, how to close the circuit (physically)
In the attached diagram, which circuit is correct. Circuit one or circuit two? ???
I always work on the premise that the only stupid questions are those that are not asked.
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tigertiger,
Use circuit #2! Circuit #1 will short circuit the battery, no lights lit, battery gets very hot, not a good idea - lol. The circuit is 'closed' ~through~ the LEDs. Or, place a switch in the line going to or from the LEDs from/to the battery (I think that sentence confused me!).
And you're right, the higher voltage LEDs on lower voltages will not be as bright.
- 'Doc
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Doc is absolutely correct. All circuit #1 would do is fry your battery in very short order!
Some mention of fusing for these circuits might not go amiss at this point? ALL wiring circuits in a model should be afforded overload and short circuit protection. The easiest way to achieve this is by inserting an auto fuse (or similar) of the correct rating in the initial (positive) leg of the circuit needing protection. Use a fuse value that is closest to, but above, the normal operating current (in Amps) of the circuit.
Modellers think of DC supplies in model boats as being pretty benign - it's difficult to get any meaningful electric shock at the normally used voltages, BUT BEWARE, short circuits that are unprotected can very quickly turn into serious fires. A short circiut might be defined as one where there is a continuous current path across the supply terminals of the power source, i.e. no device with inherent resistance in circuit.
The differences between DC (Direct Current) and AC (Alternating Current) are also worthy of mention, if only for general interest, with regard to short circuits and protection:
In a DC circuit, a short will cause an exponential and continual increase in current until someting gives, either a fuse blowing if one is fitted, or if one isn't fitted, the wiring or some other component burning until the circuit breaks itself. At higher voltages, DC circuitry is highly dangerous and has to be very carefully designed.
In simplistic terms, in an AC circuit the current reverses direction (a sinusoidal wave form) at the designed frequency, typically 50 cycles per second (Hertz) on the UK national grid. This does vary from country to country around the world. Fast operating fuses, or more commonly these days, circuit breakers, for AC circuits are mostly designed to blow or trip often within half of one cycle i.e. within 100th of 1 second. The current draw on the circuit does increase, but for such a short duration that the consequential damage is minimal. ELCB's (Earth Leakage Circuit Breakers detect current in the Earth path of the device and trip the breaker in the shortest practicable time. These have largely been replaced by RCD's in modern installations (see later post).
Given the choice, from a personal safety perspective, I would rather work on AC circuitry all the time, particularly at anything above 24 Volts.
Another word of warning, electric shocks from voltages as low as 24V have been known to kill people with certain heart conditions. And on that happy note....
My best regards,
Malcolm
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electric shocks from voltages as low as 24V have been known to kill people with certain heart conditions
Ah! So now I can achieve my longstanding ambition to fit my boat with a death ray! :D
Seriously Malc, that's very good advice. Modern batteries of almost all types now have the ability to deliver very high currents and many people are unaware of the high potential fire risk. Just look at the recent laptop battery recall for example. ALWAYS protect the circuit with a fuse or similar. It not only makes things safer but can save you a great deal of grief and money too.
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Would I be right in guessing a 1 amp auto fuse would do in most cases?
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For circuits using LEDs, yes. It is possible to get lower values intended for instrument use, but a 1A fuse will do the job. Somewhere else on the forum I mentioned using a thin enamel insulated wire - a 1A fuse will not protect this stuff, rather the other way round. Remember that the fuse is supposed to be the weakest link, so that it blows to protect the rest, and can be easily replaced when the problem is solved.
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tigertiger:-
In the attached diagram, which circuit is correct. Circuit one or circuit two? Huh
Go for circuit one, I presume your having indoor heating as well as lighting? --> Just let me know when you try it on the water and I'll get the Fireboat ready! ;D
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May I add some clarification to reply 43.
1. In a D.C. circuit under fault conditions the current will increase only to a level that is allowed by the circuit voltage (ie the battery voltage) and the ohmic value of the resistance of the fault. With a true short circuit (a very low value of resistance between the poles of the supply) this can be a high value. On a 12v supply you could be looking at around 120 to 1200A, a high enough value to completely destroy your boat wiring system quite easily. A photograph was once published of the results of someone getting their metal watch strap connected across a 12v battery. The results were not very pretty. Fusing is the only way to go to offer protection to your installation.
2. Residual Current Devices: These do not detect current in the earth path, they operate by sensing the diffference in current between the phase and neutral conductors supply a load. On a healthy circuit or installation the current in both conductors will be equal but under earth fault conditions the current in the phase conductor will be larger due to the current leaking to earth.
3. Safety (A.C. compared to D.C.) D.C. is more difficult to control in "real" situations, double pole switching and fusing is the norm and, because there is a constant current waveform (a straight line as compared with an A.C. sine wave) it is more difficult to break a D.C. circuit. This results in D.C. equipment being much larger than the equivalent A.C.
It has one "benefit" however, if you come into contact with a high voltage (mains value), normally it will throw you off.
A.C. acts on the human body very diffferently. It will cause your muscles to attempt to operate at the frequency of the supply. This often means that your muscles will seize up - and as your heart is a big muscle......... It is often a consequence of shock that the person is left hung up in contact with the live conductor (can you open and close your hand 100 times per second?) with a grip that makes Superman look like a wimp!
I hope these opinions are taken in the spirit that they are offered in. To me safety, particularly electrical safety, is essential.
Sorry to deviate from the original L.E.D. thread.
Regards
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2. Residual Current Devices: These do not detect current in the earth path, they operate by sensing the diffference in current between the phase and neutral conductors supply a load. On a healthy circuit or installation the current in both conductors will be equal but under earth fault conditions the current in the phase conductor will be larger due to the current leaking to earth.
Sorry, classic error on my part - confusing RCD's with ELCB's (it's an age thing). ;D ;D ;D
Malc
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"I always work on the premise that the only stupid questions are those that are not asked.".
Good point.
But once you've learned the answer, would the same question then become stupid again?
Sweeper:
With regards to your statement #2, you said: "RCD's do not detect current in the earth path, they operate by sensing the diffference in current between the phase and neutral conductors supply a load".
The UK 240vac system uses a method of earthing called PME. The majority of households today have their Neutral conductor bonded to the Earth. So what residual current is the RCD sensing in order to cause a trip?
What is the difference between a RCD and a ELCB?
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"I always work on the premise that the only stupid questions are those that are not asked.".
Good point.
But once you've learned the answer, would the same question then become stupid again?
Owch :'(
If the some questions recieve more than one answer... ??? or the answer is not clear to the unknowing ::) or if the answers conflict ???
I kinda hope for a little forebearance :)
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Tiger,
Don't worry mate it's not always clear what is meant, and if you don't understand ask again, and I am sure it will explained a bit better, some of the remarks you see on here should be read and either forgotten or laughed at.
Roy
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In fairness
PMK reply #38 was was very good and I am grateful for your time and effort :). You obviously spent a lot of time on the circuit diagram.
But to a total novice like me ::), there were still questions.
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All kinds of reasons why the same question can be asked more than once. It's normal for people afflicted with 'C.R.S.' syndrome, like me. Or, you may be checking to see who answered your question has 'C.R.S.'?
- 'Doc
[Only a few of us are born knowing all this stuff. We expect this type of behavior from the rest of you, don't worry about it.]
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...It's normal for people afflicted with 'C.R.S.' syndrome...
[Only a few of us are born knowing all this stuff. We expect this type of behavior from the rest of you, don't worry about it.]
Compulsive reply syndrome??? ???
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Malc,
Thank goodness I'm not the only one to have an "age thing". I feel as though I might have been around since the steaming lights were installed in Victory, one of my students suggested that I forgot about the Victory but then asked what were the conditions like on the Ark :'(
PMK,
1. True it is common practice to bond the neutral and earth together. This does not automatically make it PME. I wouldn't care to take a stab at the percentage that use genuine PME but I think that you'll find a higher proportion use a system known as CNE (combined neutral and earth). Similar principle but without the whistles and bells of a full PME setup. For info, PME was introduced primarily for use in areas where the ground conditions made it difficult to obtain a satisfactory earth electrode value. By using Multiple Earths (in parallel) this problem could be overcome. We found it not all sweetness and light back in the sixties!
2. Use of a R.C.D., the bond between neutral and earth is carried out at the supply authorities intake position. The installation is bog standard apart from this. The RCD will detect any out of balance between phase and neutral currents as a result of an earth fault being present on the circuit or installation. The conductors in the RCD pass through a laminated core which in healthy conditions is magnetically neutral (both currents being the same) but in the event of an earth fault occuring a resultant magnetic flux will circulate in the core and cause a current to flow through a separate trip coil.
3. Difference between RCD and ELCB, There used to be two types of ELCB, one current operated and one voltage operated. The current operated version is now what is classed as a RCD. The voltage type went out of use some time ago, they were very prone to failure if there was a parallel earth path on the installation as it would cause the tripping coil to be bypassed thus leaving the circuit / installation live with an earth fault on it with all the metalwork connected to the setup live.
I hope this answers your question.
Regards
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We found it not all sweetness and light back in the sixties!
Ah, you said "we". So would I right be in thinking you're an electrician, or maybe from an electrical engineering background?
And yes - you answered my questions bang-on. Thanks!
PME seems to be the order of the day around these parts. And most sparkies here - especially the young'uns - have not even heard of CNE.
In a way I'm wishing I'm never asked... I stlll have daymares whenever I'm reminded of them grotty old voltage-operated breakers (shiver!)
Anyway, thanks once again for the informative reply.
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...I kinda hope for a little forebearance :)
Hey, Tiger T, no offence meant. 'Twas written rather tongue-in-cheek. I thought you might have seen through my witty retort - it was supposed to induce a wee chuckle.
Serves me right for being a smartass.
Any questions you might have... fire away. Can't say I'll know the answer(s), but I know a man that does.
Apologies if I got up your hooter.
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PMK
Thanks :)
No problem ;D
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Great, I read both pages of this posting, and I didn't dissapoint myself. I didn't understand a word !! ??? ???
In fact there weren't many words, most of it was initials !! ::) ::)
Richard
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Whats up Richard a bit tetnicol for you mate.... :o :o :o
Roy
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Great, I read both pages of this posting, and I didn't dissapoint myself. I didn't understand a word !! ??? ???
Not something to gloat about then, eh?
Hey, Roy - nice work on the Triumph's. Beautiful, in fact.
Can't say that submarines are my thing. But your Seawolf - it caught my eye.
Scratch-built, or kit?
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It's a kit mate, Robbe type works ok, but will be better when converted shortly to become a static diver, instead of dynamic....
Roy
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Whats up Richard a bit tetnicol for you mate.... :o :o :o
Roy
Whats tetnical mate or is it supposed to be technical ::) ::)
When I've finished with English evening classes shall I send you the course papers?
I shall then do a course on tetncol bits and then all we'll have to get over is your accent :-* :-*
Richard ;)
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Maybe you ought to stay with them course papers.
Take a butcher's at your previous post. Or is that how they're teaching us how to spell 'dissapoint' these days?
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PMK,
Very good mate, he who laughs last laughs loudest,,,,remember that Richard......... :o :o
Roy
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But maybe they were coarse papers (about 200 grit I should think) ;D
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HA HA Roy ::) ::)
Told you I haven't finished the course yet!! ::) ::)
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Don't know if this is of help but here goes anyway.
I used leds on my Egrete pusher tug. Deck lights, mast lights and nav lights are all 3v superbright white leds.
Have a look at it here. - www.marine-modelling.co.uk - click on Egrete from the nav menu.
Need any more info e-mail me from the site.
Scottie
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hi Mike
God bet you didn't think you would get such a varied responce the replies got my attention .
so while you digest all the info if you pop into your local maplin they can (as they did me) provide you with a box of mixed LED's (yellow,red,green) in two sizes small and smaller for about a fiver and they will also supply you with the resistors to suit 3v,6v,9v,12v and 24v which should cover most needs.
I have them fitted to mine and the white ones are great in spotlights .I am also experimenting with white LED's in the end of clear acrylic rods as flurecent lights for walkways and wheelhouses, you gotta keep trying
daz
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:)Hi Mike
Most L/E/D will on 2 volts i/e red green etc if wish to use white L/E/D then you need at least 3 volts for them to work putting in resistors is not hard i have just wired up a model for one of our club members. Please contact all components on 01981 540781 for futher information hope this helps. :)