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    DodgyGeezer
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    Member No.#1291
    RegisteredπŸ“…18th Dec 2010
    Last OnlineπŸ“…15th Jun 2019
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    Recent Posts
    πŸ“ Aerokits Plans
    2 days ago by DodgyGeezer ( Warrant Officer)
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    "....
    I think this might be one for our 'Dodgygeezer'!? He runs a site with some vintage plans..........Just tried 'em and they don't work.πŸ€”
    At best they'll redirect Dodgy's site needs updating!....."

    Yes, indeed.

    My sites (unusually for me!) try to comply with current legislation. Very simply, this means that I need to get permission from the rights holder, or declare the item to be an 'orphan'. If you want a discussion of my interpretation of the current copyright legislation, ask for it in a separate thread!

    In general, where vintage model kits are still being sold, I do not publish plans, since these can be obtained commercially. All the plans which are available for free from my sites either come with explicit written permission from the rights holder, or documented evidence that I have researched the history and found any rights holder to be unavailable.

    That is the case, for example, for all 'Marinecraft' models, which were created by Model Aerodrome Ltd, merged with Model Aircraft (Bournemouth) Ltd, became Model Aircraft Stores, and then reverted to Model Aerodrome. At some point in the 1970/80s the kits were discontinued, and Model Aerodrome was sold to an entrepreneur in 1987 who resurrected the business under the name 'ModelZone'. This went bust in 2013, and W.H.Smith bought the name to sell imported model cars under. Their legal department do not seem to know whether with that they also obtained the rights to some model boat plans designed in the 1950s by a company started in the 1930s. Nor do they seem to care. They have, of course, no existing plan data, so as usual I have to reverse engineer from surviving examples..

    Tracking this kind of thing is complex, and the Aerokits models have been through a bewildering series of ownership (and claimed ownership). Often this seems to be the same people trading under different names. At the moment SLEC seem to be making (and selling) the kits, while Cornwall Model Boats, Jotika, Lesro and Vintage Model Works and a good few others all distribute them. Of particular interest is Belair, who have an agreement with Colin Smith to produce the old Phil Smith range of kits. But while all these are being commercially provided I will refer plan requests to the rights holders.

    Tracking all this it time-consuming, but it looks as if I should do a bit of link updating at some point...
    http://www.belairdigital.co.uk/content.asp?id=13
    πŸ”—

    models
    Model Aircraft
    model cars
    Cornwall Model Boats
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    πŸ“ Reversing Field-Wound motors
    2 days ago by DodgyGeezer ( Warrant Officer)
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    I would pause a bit with promises. AFAICS, this approach is quite novel, so it's untested beyond my desk. And while I may think it's fine, someone else may find all kinds of issues with it. Different frequencies and/or pulse formation compared to my ESCs, for instance, might create instability, even though the simulations look OK. This is still 'bleeding edge' work, I'm afraid...
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    πŸ“ Reversing Field-Wound motors
    3 days ago by DodgyGeezer ( Warrant Officer)
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    That would be very useful! It's not a lot of components - and you don't need to drive a relay. Just an LED would show the operation, though to ensure that you don't get relay chatter you really need a complete circuit and a big, noisy motor to test...

    Here is a pic of one of my test boards - power from the battery on the left, while the (input and output from the ESC) are on the right...

    Correction - for 'input and output from the ESC' read 'connections to the cross-over coils'. πŸ€”πŸ˜Œ!

    relay
    test boards - power
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    πŸ“ Reversing Field-Wound motors
    3 days ago by DodgyGeezer ( Warrant Officer)
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    Field-Wound motors - of which Taycols are the commonest example for model boating - used to be used extensively as hobby electric motors until the Japanese started producing decent permanent magnet motors in the 1960/70s. They are not easy to reverse, however, requiring a polarity switch of the field coils, OR armature coil, but NOT both. This means that vintage modellers cannot easily use a polarity-reversing radio control ESC to control such a motor.

    A common technique to address this problem uses a diode rectifier to maintain the initial polarity on one set of coils while letting the others be driven in reverse. This is a simple to apply solution, but it has a few drawbacks - it lowers the voltage available for forward running, for instance. An ideal method of reversing would be to switch the coil connections as specified by the original designer.

    Such switching could be done physically by an extra servo, but that brings its own ergonomic difficulties. A better method would be to detect the polarity change and switch the coils using a relay. The circuit below is designed to do this, with few components (though more, of course, than the rectifier!)

    The PWM signal is smoothed, then fed into an op-amp acting as a comparator. Hysteresis around the switching point is achieved with a resistance feedback. This seems to cope with the problem of generated back-emf interfering with the polarity detection quite effectively. The output switches a 5-20A relay (depending on the motor being used) via a mosfet. The relay is, of course, set so that it is on for reverse, so that the only circuit drain during forward running is the op-amp, which is a matter of uAs.

    This approach appears to be novel - I can't find anyone else doing it - so I am cautious about recommending it for widespread use. I have tested it on several ESCs and motors, and put it through simulators on a circuit forum that I follow. The circuit seems to work reliably with these component values, but I would appreciate it if someone else would trial it with their system. There are so many different ESCs out there that it would be hard to test them all!

    There are some PIC-driven polarity-detector units on the market place for other purposes - reversing steam engines or water-jets, for instance. I have tried one, and found that motor interference made the logic circuits very unstable. Using a standard op-amp avoids that problem.

    motors
    relay
    op-amp
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    πŸ“ Battery backup
    3 days ago by DodgyGeezer ( Warrant Officer)
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    "....Hi Dodgy, welcome backπŸ‘
    I see you've been tickling the grey cells. BrainstormingπŸ‘
    "The web is full of low-battery detection circuits ... "..."

    Yes - I've been thinking about reversing Taycols. The diode rectifier method is very simple, but does drop a volt or two, and I was wondering about a more elegant solution - which I think I have now. Unfortunately no one else has ever wanted to do this, so there are no prior examples on the web that I can find. Apart from this one now...

    I will put something up on another thread, because it's only peripherally connected with battery back-up....
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    πŸ“ Battery backup
    3 days ago by DodgyGeezer ( Warrant Officer)
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    The web is full of low-battery detection circuits - including those with latchable switching to stop the circuit turning back off when the main battery recovers voltage as it is rested. See the link below.https://www.google.co.uk/search?client=opera&q=low-battery+detection+circuits&sourceid=opera&ie=UTF-8&oe=UTF-8

    An alternative approach might be to detect, not the dropping of a voltage to some specific level, but the actual failure of the R/C signal at the servo due to low voltage. You can do this with a 555 easily enough and less than half a dozen components - this is often used to drive a sound generator to find a missing aircraft (just turn off the radio), or some other failsafe action. For instance http://www.circuitstoday.com/missing-pulse-detector-circuit-...

    A latchable missing pulse detector coupled to a switch to add a single C NiMH battery to the main power (and an LED warning) would let you get the absolute maximum out of a battery and then boost the voltage sufficiently for a short home run. That is, if you want to run your batteries down to their limits and you are running on such a low voltage that the BEC is the first thing to go. You could also take pulses off the prop-shaft if you didn't mind the circuit switching in whenever the boat stopped.... 😊

    Usually, a boat running slowly would be the best indication to come in and change batteries....
    https://www.google.co.uk/search?client=opera&q=low-battery+detection+circuits&sourceid=opera&ie=UTF-8&oe=UTF-8
    πŸ”—
    http://www.circuitstoday.com/missing-pulse-detector-circuit-using-ne555
    πŸ”—

    battery
    sound generator
    batteries
    boat
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    πŸ“ Glue
    1 month ago by DodgyGeezer ( Warrant Officer)
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    That is indeed a bargain!

    I have noticed that my small bottles of MEK tend to disappear through evaporation more rapidly than through use! Have you noticed any such issue?

    bottles
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    πŸ“ Recent Down Time
    1 month ago by DodgyGeezer ( Warrant Officer)
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    "I wonder how many of such actions goes back to the international fight against terrorism.."

    You can actually trace it back to the fall of the Berlin Wall, and the realisation shortly afterwards that an influential community was short of an enemy which justified its existence.

    I try to run my life on fixed principles (which is a foolish thing to do - vide Socrates), and was very unhappy about the Western response to the end of the Cold War. But discussing this would move us into politics, and I cannot see a Politics thread on this site (for which I am deeply thankful!). I will therefore say no more.

    My principles also encompass Richard Stallman's approach to the web, in that everything ought to be freely created. You will note that the four web sites I run neither have adverts nor do they solicit cash donations. People have tried to provide these in the past, and I have turned them away. So I have also established my position on that very many years ago...
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    πŸ“ Recent Down Time
    1 month ago by DodgyGeezer ( Warrant Officer)
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    ".....More concerning is that they are even scanning the databases... that does mean they're checking through all user data.............. I personally think it's wrong that they do this. Albeit a robot that does it..."

    Given the current move towards extensive web censorship by the Government, and the consequent legal impact on any site which is held to be in breach, I can see why your web host does this. They could well be following Government direction to do it. They may also be required to secretly report any suspicions they have, like the 'Prevent Duty' for schools. See https://www.gov.uk/government/publications/protecting-childr...

    False positives from this are going to be fun...



    "....If spam is in the database, it's pretty harmless unless it's executed on the website and there are measures in place to prevent code from being surfaced...."

    I wouldn't think of Spam as being executable - if it is I would count that as Malicious Software, and I would have a policy of removing it to a safe repository immediately. And telling the Webmaster...

    There is a balance to be attained between being fairly safe from Web attacks, and being able to operate with minimum disruption. It is up to your host's security team to define and maintain that balance, and they really ought to gain customer agreement and involvement in how they do that.
    https://www.gov.uk/government/publications/protecting-children-from-radicalisation-the-prevent-duty
    πŸ”—

    Malicious Software
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    πŸ“ Glue
    1 month ago by DodgyGeezer ( Warrant Officer)
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    Pool Noodles are the foam insulation for pipes, used as flotation devices. See https://en.wikipedia.org/wiki/Pool_noodle

    They can be used as fenders for large model boats, and look very similar to the inflated tubes in an RIB, so they can be used to make RIB hulls. But joining them and shaping them is often a problem...
    https://en.wikipedia.org/wiki/Pool_noodle
    πŸ”—

    Pool Noodles
    flotation devices
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    πŸ“ Recent Down Time
    1 month ago by DodgyGeezer ( Warrant Officer)
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    "The hosting company say the database was locked by the security team as SPAM content was detected in the forum table. Getting it unlocked proved slow and now it is unlocked, I can't see any issue with it."

    That raises a lot of questions!

    Did they know that locking the database would drop the site for 24 hours? If not, they made a technical error. If they did, I would like to see the security justification for this.

    Malicious software - maybe close down the site if you can't clean it immediately.

    Spam - surely inform the webmaster and ask what should be done? The spam would have to be very bad to take the site off-web. And surely you would be able to show the webmaster what the problem was later?

    I wonder if there was a technical balls-up and this is a convenient excuse? Security is NOT about closing things down if you hear a rumour that there might be a problem - it's about running a business so that there are no nasty surprises. The security team is responsible for running a service just as much as the ops team are. Security should be running things safely - with the accent on 'running'. If they don't, they are just another DoS threat.

    I would ask for a report from security which includes the reason for the locking decision...

    software
    DoS
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    πŸ“ Brushed to Brushless upgrade
    1 month ago by DodgyGeezer ( Warrant Officer)
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    In some respects you can think of a brushless motor as part way between a standard brushed electric motor and an I/C engine.

    The brushless can turn on and off like the electric motor, and is clean like the electric motor.

    It has a high power-to-weight ratio like the I/C engine, can't run slow like the I/C engine, and you need to make sure that the heat is flushed away....
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    πŸ“ Brushed to Brushless upgrade
    1 month ago by DodgyGeezer ( Warrant Officer)
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    "...I am much wiser about this subject now..."

    Court comment attributed to the famous barrister F E Smith, in the early years of the 20th century:

    "Judge: Smith, I've listened to you for an hour on this case and I'm still not one bit the wiser.
    Smith: None the wiser perhaps, my lord, but certainly better informed."

    😁
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    πŸ“ Brushed to Brushless upgrade
    1 month ago by DodgyGeezer ( Warrant Officer)
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    "...So would you say that if you made something like my HMS Cottesmore (1/48 scale) and was to run it at more realistic speed it would be better to use brushed motors?..."

    1 - Do what you are happiest with, and experiment to learn more...!

    2 - Brushless are a more efficient motor type, use a more advanced technology, and will probably supersede brushed technology at some point. They are being used more and more often in household appliances. I expect that we will eventually move to them 100%.

    3 - I don't know your particular model, but if you moved to brushless you would get more power and a longer running time out of the same batteries - though maybe not enough to notice...?

    4 - If you want to maintain slow running, you might think about gearing the brushless down, or using a Sensor motor. Both of these options involve extra cost, and you might not find the performance advantage worth while. Sensor prices seem to be coming down, so that might be something to think about for the future. That's probably what I would use if I were making a big slow-speed model at the moment...

    motors
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    πŸ“ Brushed to Brushless upgrade
    1 month ago by DodgyGeezer ( Warrant Officer)
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    ".....brushless motors the main question is speed controller as I would need forward and reverse...."

    Simple answer.

    You can get reversible brushless ESCs. However, watch out, as boats are a minority interest and many cheap reversible brushless ESCs are designed for car use. These may have a 'braking' feature, which means that the controls work like this:

    forward stick = forward
    backward stick = motor braked
    quick forward and backward again = motor goes in reverse

    which is optimum for cars, but cumbersome for boats. A proper boat designed brushless ESC will be fine, as will be a cheap car one where you can turn off the 'brake'. RNinMunich recommends the Quicrun series of Chinese brushless ESCs, but of course products change all the time.

    So check that the ESC you are after is reversible, and has a 'no-brake' setting....


    Rather more complex background explanation.

    This is my understanding of how one particular 'brushless' system works - there may well be other technologies out there... :

    'Commutation' is the process of switching each coil in an electric motor on at the right time to get attracted to the nearest magnet and off when it passes the magnet, so that the armature will rotate in one direction.

    In a brushed motor this happens mechanically, and we don't need to worry about it. If you want to know a bit more, get a Taycol motor and start reading papers like this: http://what-when-how.com/electric-motors/commutation-electri...

    In a brushless motor, commutation is done by software inside the ESC. So the ESC is essential to a brushless motor - it won't run without one.

    What the software in a brushless ESC does is start the motor with a pre-programmed series of activations of coils. Once spinning, the software detects the generated back-emf as a magnet passes each coil, and uses this to work out the motor speed, timing, and hence which coils to activate next, depending on the throttle signal. Obviously, this happens very fast.

    If the motor went round slowly, the generated back-emf would be very low, and the ESC would have difficulty detecting it. So a typical brushless motor has a minimum speed which is quite high compared to a brushed motor.

    In a sensor motor, the ESC can be much more precise about timing because it reads it off the Hall-effect sensor. It can also run at much slower speeds. But the extra kit, and the low production levels mean that these are going to be more expensive motors.

    For a brushless ESC the starting process, and the reversing process, are much more complicated than they are in a brushed motor. In each case the software has to try to detect what the motor is doing and adjust the timing to get it running in the right direction 'blind', with possibly odd feedback from the coil back EMF. For a brushed motor, the ESC just reverses the polarity and the mechanical commutation automatically applies a force in the direction you want.

    The result is that brushless starts can be a bit jerky, and brushless reverses need 'setting up' with a process of signalling from your transmitter or using a program card. Since cheap brushless ESCs are often turned out with little documentation, making them reverse can sometimes be difficult for an inexperienced purchaser.
    http://what-when-how.com/electric-motors/commutation-electric-motors/
    πŸ”—

    stick
    car
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    cars
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    πŸ“ Help me please
    1 month ago by DodgyGeezer ( Warrant Officer)
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    I use this fairly extensively.

    https://www.lutonmodelboat.co.uk/hints/RC%20Switch%20Iss3.pd...

    The advantage is that you have complete flexibility - you can build a cascade of switches or switch multiple voltages as you require...
    https://www.lutonmodelboat.co.uk/hints/RC%20Switch%20Iss3.pdf
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    πŸ“ Brushed to Brushless upgrade
    1 month ago by DodgyGeezer ( Warrant Officer)
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    Yes - S3 / S4 etc refers to number of cells in a Lipo. Lipos are 3v-4.3v per cell, need special chargers and critical care compared to the more robust NiMh batteries. Unless you really need the small, light, ultra- powerful Lipos for racing or something, I think it's best to stick with hi-power NiMh cells.

    S4
    Lipo
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    πŸ“ Brushed to Brushless upgrade
    1 month ago by DodgyGeezer ( Warrant Officer)
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    "....that is why I was looking at this thread with interest.
    As I hoped to learn something!."

    My thoughts about brushless motors...

    - they are a different kind of motor, so they have different characteristics. In particular they need different ESCs.
    - Their ESCs come with three cables. You can connect them to the three inputs to the motor in any order. If you want the motor to go backwards, simply reverse any of the two connections.
    - you can get In-runners, which are high-speed ones. Out-runners are higher torque ones. There is a special type called 'Sensored' which can go very slow and are used for rock-crawling vehicles, but they need special Sensor ESCs and are expensive.
    - they are much more efficient without a sparking commutator to pass electricity through.
    - they don't have tight limits on the voltage they must be run at. More volts = more speed, and hence power.
    - they are happiest running at high speed. They don't much like trying to run slowly, and tend to start with a jerk.
    - the main limitation on them is thermal. You can run them until the coils get too hot for the magnets to work (upon which they are fatally damaged!).
    - you can get astonishing amounts of power out of quite small sized motors if you give them enough electricity and keep them cool. They suck up power from batteries given the chance, and high-output batteries like Lipos are ideal for them. If you use other batteries, check that the battery can output a lot of power - if it can't, the brushless performance may be disappointing...
    - I find it is best to run them at low voltages (12V or less) at which point they don't heat up at all. The motors are often capable of running from 6v to about 20v...
    - Rather than power, the motors are measured on size of can and KV. KV is the speed in RPM that each volt will produce. So a 1000 KV motor will do 12,000 RPM on 12V. If it is specced as a 2824, that means it is 28mm wide and 24mm long.

    - Cooling is important, and hard to specify precisely. Depends on the power being used, and the cooling technology you provide. Most brushless are designed to run in aircraft where there is lots of cooling air. For boats, you can get cooling jackets for in-runners and cooling mounts for outrunners. Having some air throughput is a good idea - but hard to arrange on a boat... Unless you are sure that you are running well below the power limits, you should use a Watt-Meter to track the power usage rather than try to calculate things. This discussion may provide an idea of how to worry about brushless motor limits:
    https://www.rcgroups.com/forums/showthread.php?1329612-Brush...
    https://www.rcgroups.com/forums/showthread.php?1329612-Brushless-motor-rated-voltage
    πŸ”—

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    πŸ“ Help me please
    1 month ago by DodgyGeezer ( Warrant Officer)
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    Something like this will switch an LED lighting circuit on. If you want more complex lighting switching you can get more complex switching solutions, but this is simple and cheap. Takes 1 channel...

    https://hobbyking.com/en_us/turnigy-receiver-controlled-swit...
    https://hobbyking.com/en_us/turnigy-receiver-controlled-switch-1.html?countrycode=GB&gclid=EAIaIQobChMIlb_HwYGW4gIVibHtCh0ZPwayEAYYASABEgLuEfD_BwE&gclsrc=aw.ds
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    πŸ“ Help me please
    1 month ago by DodgyGeezer ( Warrant Officer)
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    "...what would be good is what you need is this speed controller this for the leds ect ..."

    Every modeller has their own preferred set of materials, equipment, etc. I tend to go for very cheap kit - other people will prefer more expensive and more reliable items.

    I'd be surprised if a motor specced at 1-2A would exceed 80A under stall. Are those figures no-load rather than under optimum load? If so, we may be looking at 5-10A under running conditions? That still sounds a lot - I might expect 2-5A running, and fuse at 10-15A. So you might use an MTronics Viper 20 like this: https://howesmodels.co.uk/product/mtroniks-viper-marine-20-p...

    The drain will depend on the battery capability, of course. I tend to design for 7.2NiMh - that means that it is easy to drop the voltage to 6 or rise it to 12 if I need to. You will need a bit of ballast for that boat - you might find that lead-acid can provide the power needed, and that would also provide the weight!

    If you want to decide based on data rather than ideas from others. perhaps it would be a good idea to actually measure the drain under running conditions? Do you have a recording wattmeter? If not, just go to ebay and search for 'Watt Meter Power Analyzer'. For about Β£8 you get a little blue box that attaches between battery and motor, and records current and maximum power drain...

    https://www.ebay.co.uk/itm/Digital-Monitor-LCD-Watt-Meter-60...
    https://howesmodels.co.uk/product/mtroniks-viper-marine-20-plug-n-play-electronic-speed-controller/?gclid=EAIaIQobChMI-72y5fmV4gIVibPtCh099gtiEAQYAyABEgKaI_D_BwE
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    https://www.ebay.co.uk/itm/Digital-Monitor-LCD-Watt-Meter-60V-100A-DC-Ammeter-RC-Battery-Power-Amp-Analyzer/362444865559?_trkparms=aid%3D1110001%26algo%3DSPLICE.SIM%26ao%3D1%26asc%3D20131231084308%26meid%3Df08eeb60704a4dd2a85883d23b7b8959%26pid%3D100010%26rk%3D5%26rkt%3D24%26sd%3D362580489901%26itm%3D362444865559&_trksid=p2047675.c100010.m2109
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    equipment
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    πŸ“ Help me please
    1 month ago by DodgyGeezer ( Warrant Officer)
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    So you already have an appropriate motor installed. All you then need is a radio (Tx and Rx), a servo, a speed controller and a radio-switch if you want to add switchable lights. Oh, and a battery.

    You will need a radio because 35mhz is an aircraft band. Boats can use 27mhz, 40mhz (both old technologies now) or 2.4ghz. I would strongly recommend 2.4ghz - it's cheap and has lots of advantages. You can get a set for less than Β£50 - I have seen them for less than Β£20! But get one with more than 2 channels if you want to do extra light switching.

    The hull is a displacement one - I suggest a standard 7.2v NiMh battery pack (though I don't know your motor voltage?). Do you have a charger?

    radio-switch
    Boats
    charger
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    πŸ“ Help me please
    1 month ago by DodgyGeezer ( Warrant Officer)
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    Do you have a radio control? And what is your budget? Do you have a brushed motor?

    Broadly, I would guess that you have a wide choice between cheap Chinese from HobbyKing or Ebay, or more professional kit from somewhere like Action Electronics...

    kit
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    πŸ“ Brushed to Brushless upgrade
    1 month ago by DodgyGeezer ( Warrant Officer)
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    "A Hobbyking 3639-1100kv 800Watt on a 3S 5800mah Lipo battery with a 100Amp ESC and for a prop 2 blade 40-45mm.
    If you require a faster motor a 3648-1450kv is a straight change over with all the other bits the same.
    Also you can change the battery to 4S and it will be a rocket...."

    How hot would that get, and what sort of cooling would be needed?

    I have a number of 36mm brushless that I would like to try out, preferably with high-output NiMh batteries. The largest brushless I have is a 42mm, and I really don't know what that would be suitable for...

    Hobbyking 3639
    800Watt
    batteries
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    πŸ“ Ace Nautical Commander
    1 month ago by DodgyGeezer ( Warrant Officer)
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    ".....don't want to stick a finger up and say 'Here I am, come and sink me!'
    That was DΓΆnitz's big mistake in the Battle of the Atlantic! "


    It is hard to make general statements about the technology in the Battle of the Atlantic, since to a large part it was a technological battle, and the balance between the relative capabilities of different technologies altered - sometimes on a monthly basis or less!

    RDF was well understood by the Axis powers, and they were required to keep their messages short to avoid a fix. For a mechanically rotated aerial, which the Germans used, getting a fix required a fair bit of time, and getting an accurate fix could take a minute or more. Shore stations then had to transmit the information to interested parties, and so a U-Boat was fairly safe if it sent occasional short messages and kept moving.

    I believe that the Royal Navy responded with the Huff-Duff dual loop antenna which you will find on
    most RN ships of the period, feeding into a CRT PPI indicator. This could give immediate accurate directions, sufficient for an attack to be mounted directly down the bearing. Though, of course, this could also be used to tempt a corvette off station to enable another boat to attack. It had originally been developed to track lightning strikes...

    LΓΌtjens, of course, sent a famous long message enabling precise identification of the Bismark, but the British then made a plotting error and sent their Task Force in the wrong direction for a while....

    CRT PPI
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    πŸ“ Ace Nautical Commander
    1 month ago by DodgyGeezer ( Warrant Officer)
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    Looks like not - though that site has a lot of useful other 'how-tos'. See link.

    I wouldn't convert a Tx by carving the existing sticks away anyway - I would make a new unit with plugs to go into the existing radio. I just found that site on a web search, and put it out to show that this was what some people were doing...
    http://wmunderway.mysite.com/cont/cont.htm
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    πŸ“ Ace Nautical Commander
    1 month ago by DodgyGeezer ( Warrant Officer)
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    This article might be helpful...
    http://wmunderway.mysite.com/cont/twinstick/twinstick.html
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    πŸ“ Ace Nautical Commander
    1 month ago by DodgyGeezer ( Warrant Officer)
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    Twin stick systems are much sought after by scale boat enthusiasts - and command a high price everywhere.

    27Mhz / 40Mhz systems are sought after by submariners...

    I have not needed a twin-stick, but I have thought that if I ever did I would simply make one. Much cheaper! The pots don't need complicated self-centering, they just need mounting sideways and having a stick joined to each, with perhaps a friction pad. You can buy commercial dual sticks of course - at a high price - but I suspect that anyone with a lathe could make ones equally as good.

    And then you could have a cheap 2.4Ghz Tx with a unique fitting...
    https://www.krickshop.de/Electronics-Motors/R-C-Sets-and-accessories/RC-Sets/Accessories/Futaba-F-14-FC-16-Twin-Boat-Stick.htm?shop=krick_e&SessionId=&a=article&ProdNr=roF1564&p=347
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    stick
    lathe
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    πŸ“ Ace Nautical Commander
    1 month ago by DodgyGeezer ( Warrant Officer)
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    It might be a shame to alter the innards of such a radio - vintage radios like this make a lot of money if sold in original condition. See https://www.rcgroups.com/forums/showthread.php?2980389-ACE-N... Perhaps $200?

    To convert it to 2.4Ghz you would have to obtain a 2.4Ghz transmitter module. If you can do that, you can probably obtain a full 2.4Ghz combo and use that radio if interference is the primary issue.

    To convert you need to obtain a radio module, and then find the position in your transmitter where the signal is passed to the RF section. You then connect Vcc, GND and Signal to the new 2.4Ghz module. Some radios have a separate RF board, making this part easy, but if not you will need some way to find the bit to connect....
    https://www.rcgroups.com/forums/showthread.php?2980389-ACE-Nautical-Commander-7-ch-NIB-AND-FOR-SALE-AGAIN
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    radios
    transmitter
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    πŸ“ Rivets
    1 month ago by DodgyGeezer ( Warrant Officer)
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    "....although I did try some as an experiment and broke a pair of small cutters so ended up using pliers.
    They're tough little things to cut..."

    Decent quality dressmaking pins are made out of hardened steel, and are probably best cut with a Dremel disk.

    The cheapest Chinese Ebay pins are often made out of soft wire, and are easy to bend or cut. They are useless for dressmaking, but they are cheap, and would do this job perfectly...

    pliers
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    πŸ“ NAAMA Tug Plan
    1 month ago by DodgyGeezer ( Warrant Officer)
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    You don't often hear of that kind of luck! Can you choose my lottery numbers next week? !!
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