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A somewhat confused question if I may say so Eric!😲 You can't 'regulate up' only down. The regulator's job is to produce a constant lower voltage from a range of higher voltages. I often use one to produce 5V for the RX and servos from a 12V SLA drive battery. A little 3 legged device (type LM7805) which looks just like the power FETs in a high current ESC. My version of a UBEC! 😉 What is this 'regulator' you have? Type number? Manufacturer? Photo? To get 12V from 7.2V you would need to use a Voltage converter (also known as an inverter). This works by converting the DC input from the battery to an AC voltage which can then be increased using a transformer. More elegant (and expensive!) versions use a transistor oscillator and amplifier. This uses hi-power transistors instead of the transformer. The AC output of the transformer (or amplifier) is then rectified back to DC. All this is very inefficient which is why it is normally only used for very light currents, where the losses are not so significant, and when there is no other alternative, not often the case! You can't beat the physics and you will never get the same power out that you put in. This leads to a basic design question:- What is the total current consumption of the load? I.e. the motors. A simple example:- Let's say that at 7.2V the motors draw 10Amps total, i.e. 72W (or VAmps). Assuming a utopian 100% efficiency at 12V this would equate to 6A. Due to the three stages of conversion; DC to AC, transformation / amplification of AC to 12V, AC back to DC, you'll probably be lucky to get an efficiency of around 60% to 70%. Thus if you stick 720W in you'll get around 430 to 504W out. Not much of a gain is it!🤔 Your battery would be exhausted in about 2/3 the time it is now 😡 If your motors draw more than 10A the problem just gets worse. So what is it you really want to do? If you just want to up the volts to your motors stick a 12V SLA or an 11.1V LiPo (3S) in and hope that you don't cook your motors! Frankly I don't really know why you're bothering, tugs aren't sprinters! If you want more pulling power with the existing setup try experimenting with prop sizes and pitch. Will probably achieve much more than fiddlin' about with voltage converters. BTW: All this assumes that the RX has it's own separate 5V battery supply or from a BEC in the ESC. Some clarification needed from your side. Cheers, Doug 😎
The weather has quickly turned colder, giving an excuse to get back to this model. Stripped out much of the interior and the prop. shafts to replace the nylon propellers with brass. These items all needed removing for painting, so decided to paint the hull before reassembly and then moving onto the superstructure. Fortunately, examining similar naval vessels and several U Tube videos, confirmed the hull as light grey, the deck a darker one of the 50 shades of grey and the lower hull below the waterline black. Used thin Tamiya masking tape to define clean colour separations, followed by regular tape, masked the hull into colour sections and sprayed using “rattle” cans. After the colours applied a light overall Matt coat to subdue any shine. The results are satisfactory. Will now reassemble and move onto building the superstructure and the other fittings. Prior to the season closing decided to experiment with my new Flysky Tx/Rx package, shortly to be fitted to this model. This Tx has a servo limiting function, which was hoping could also be used to restrict ESC output. Would like to make the full speed motor response correspond to full Tx control position. Currently can over power the model; which lifts the stern, causing it to come off the plane and then dig the bow in. Was thinking that if full throttle could be set at around 90% forward control movement and 40% sternwards the model would retain adequate performance, but without being overpowered or very sensitive to control lever movement. As the Brave was not available, tried the idea on my Daman Stan 4207 model. This is brushed motor powered and a good performer. Obviously the settings for the Brave will be different, but at least could try to see if the idea would work – it did! This Tx function is easy to use and adjustments can be made whilst the model is on the water. Once the ideal settings are achieved they can be programmed and then retained in the Tx. Will try this on the Brave when back on the water next Spring.
Hi TJ, Answer to both questions is NO! 1 Connecting all the ESC switches together is like leaving all three of the red wires in the RX leads connected. If you mean a main power switch for the ESCs (not the little slide switch attached to the ESC) then consider that the switch would have to cope with a current of 3 times the max current rating of the ESC!!! For example; for 30A ESCs that would be 90A 😲 pretty big switch! 2 The object of the mixer is to control the ESCs of the two outer motors depending on the rudder setting, not to replace them somehow. If you mean two of the little slide switches being made redundant; again NO! They are there to switch on the ESC's internal circuitry, incl. BEC, without it they won't woik 🤔 Cheers, Doug 😎
Your more than welcome TJ. Re paragraphs etc; was a well meant 'Word to the Wise', just to make your interesting contributions easier to read. 😉 Keep up the good work👍 Which configuration did you decide on in the end? On my single screw boats, like my Sea Scout, I tend to just use the BEC from the ESC and no separate RX battery. On my multi screw ships, the majority actually, from two to four screws (PTB to HMS Belfast cruiser) I always use a separate RX battery. On the basis that I reckon that the drive battery already has enough to do 😉 So I use 4.8 or 6V NiMh batteries of around 1500 to 2000mAh. Always put a switch between the batt and the RX. Also a switch and a fuse, approx 5A lower than the ESC max current rating, between the drive battery and the ESC(s). All the best, Doug 😎
Hi TJ, RE: RX battery. Any 4 or 5 cell (4.8 or 6V) NiMh of 1000mAh up will do. Use the biggest one you can without upsetting the boat's trim or reducing it's performance / planing etc. BUT: don't forget to disconnect the red wires between your ESCs and RX to disconnect the BECs in the mTroniks speed controllers!!! Also check that your RX and mixer module etc can handle 6V+! If not use the 4 cell pack. A fully charged NiMh will be significantly above 6V. Some modules; e.g. Action Electronics / Component Shop don't like that 😡 Alternatives are, esp if you need to save weight, 1 use ONE of the red BEC leads from ESC to RX, e.g. the centre one, and disconnect the other two, 2 Use a separate 5V UBEC module to syphon power off the drive battery for the RX, AND disconnect all three red BEC wires from the ESCs. Cheers, Doug 😎
Basically ads is correct, but that's only half the story! The clue is to look for 'LiPo Safe' when buying ESCs. That tells you it has a programmable Cut Off voltage setting to prevent damage to your battery. Default is usually 3.2V per cell. Absolute minimum is 3.0V. Below that you risk irreversible damage to the battery due to chemical changes that can't be reversed. The alternative is to fit a battery monitor which can trigger an audio and/or visual alarm to warn you to 'make nearest port best speed' before your battery is deep discharged, from which it will not recover! Some ESCs have a programmable function which allows to preset a reduction of the max power to the motor (instead of a total shut down) to give you the chance to get home before disaster. PLEASE don't ask me which ones. Check the specs carefully before you buy. Many current TX/RX sets will tell you on the TX display when the battery volts are low. Cheers, Doug 😎
Does anyone know if a Sanwa Rx will work with Futaba Xtals. Both 35 mhz (planes only)👍🤔 More modern battery packs can replace the old DEACS so no probs there Westie.👍 I too use Bang Good and also Gear Best Both excellent.👍
Thanks jbkiwi, 2.4ghz isn't a problem, most of my vintage rx's are from the 60's through to the 80's. 27mhz and 40mhz. But it's good to have all the information I can get about all systems as I expect 2.4ghz will become vintage one day. Cheers Colin.
The FSR6B will work with the FR Sky i6, i 10, T6 (which might be the HK-TR6A-V2), CT6B AND TH9X (which is the 'Hobby King' (FR Sky) 9x). I have bought the (Fly Sky) FSR6B and the FSR9B (8CH) and they both work fine on the 9x. Not sure what the difference between FR Sky and Fly Sky is, but it's probably just branding. I think Hobby King puts their own names on everything and modifies model numbers just to confuse everyone, like saying only their receivers match which is not true (perhaps in their product line but not in the real world) you just have to look around and take a punt. FR Sky make the TH9x (HK 9x) probably the 9XR for HK, the Taranis and a few others. Fly Sky seems to make the cheaper ones i6 (which I think has replaced the 6df) TR6a HK-6DF TGY 6X (hard to find the XR5000,- 7000 RXs anywhere for the 6x) etc. It might be worth a crack at the 6ch FS-R6B receiver as the matches mention a T6 TX, not much to loose and if it works, buy a bunch (check EBay, AliExpress and Banggood,-prices vary for the same items) like I did just in case HK dumps it and leaves everyone high and dry, as they have with a number of products. Now days you have to do lots of research and risk a few dollars to win, with all the B/S you get from suppliers,-not just R/C.
Hi Bryan, I have found problems, even with matched crystals, the usual problem is that the some of the old rx's would not operate with a tx from a different manufacturer. I have acoms, futaba, Fleet and magregor as well as some unbranded tx's, but some of the models which I have aren't working with tx unless it's the same brand as the rx. This problem is mostly on the 27mhz models, although a couple of 40mhz systems have had the same problem. I always buy matched pair crystals. Even some am sets which never have a problem. So I thought if I can make a chart showing what is compatible with what. Cheers Colin.
Colin, when Doug repaired my faulty (at factory) Spektrum DX5e Tx, I sent him my Orange 6 channel Rx and a recently bought black one (just a number) and he bound both to the repaired Spektrum. I think you only need to make sure the compatibility with the operating system is right. But I'm sure he can explain all that better than I. Martin
As a vintage model restorer and user it would be handy to have a chart showing which branded tx's will work with which rx's. I have an assortment of radio gear from the early 60's to quite modern 90's, but as most of the models I have were donated to me without either the tx or occasionally the RX sorting out with such a chart would be easy. 27mhz and 40mhz. Along with the more recent 2.4ghz. Could be split into 3 sections, to show compatibility. Sounds like a challenge, but together we could compile such a chart. ANY TAKERS. Cheers Colin.
I know what you mean, i have altered my Mcgregor TX to Futaba, the receiver was gutted and a Futaba RX hidden inside!!! this was for use on some 60's models so it looked the part, modern internals with a retro outer case
Evenin' Mike, I like and agree with your basic attitude👍 BUT- How's your electronics!? Whereas it MAY be possible to obtain a 2.4Gig TX module for the Mac (but I doubt it cos it's probably too old) there's no way you can mod the RX to match. And which hopping system would you use? FAST, HOTT, AFHDS ...? Assuming you can find an appropriate TX module you'd have to replace the RX anyway. Your best bet might be to look for a 40MHz TX module, there were a number about before the 2.4 craze started! You'd still have to replace the RX though, unless your electronics is up to a rebuild and retune! And make sure you have a match; AM, FM, PCM, PWM ?? The UHF (459MHz) sets never really got off the ground(!😲) so modules for those are probably as rare as rocking horse droppings! Look for 40Meg bits. Bon chance mon ami,👍 Cheers, Doug 😎
Hi John, think somehow you've got the wrong end of the stick!🤔 All BECs are Battery Eliminator Circuits of one sort or another. The objective is to eliminate the separate receiver battery, sometimes necessary purely to save weight and/or space in small models. If you do that then the RX power must come from the main drive battery, which then has to supply all RX functions; servos, switched lights etc etc. Personally, if the boat / ship can carry it, I prefer to use drive batteries for just that and use separate battery for the RX and special functions. Some of which, like smokers for instance can be current gobblers. Cheers, Doug 😎 PS If you ever find a way of eliminating all batteries and still get the RX to work and the boat to move PATENT IT QUICK!! 😁 Cheers, Doug 😎 Hmmm! Maybe a raft towed behind with an array of hi-current solar panels!? 😁😁 Years ago in my work in NAVAL COMMS systems I once suggested to a shipbuilder, who was complaining about the number of antennas needed, to put some of them on a raft behind the ship 😉 Now they are doing just that with antenna buoys from submerged submarines! No credits 🤔 ... SIGH 😉