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fastfordrc

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  1. hi, just checked out your old item about converting old transmitters with hacking modules.

    Unfortunately your pics have disapeared (thx to photobucket...). I want to try it with an ond Graupner C4-X. As listed in your description, only thing I couldn't figure out is: cutting the track at the yellow line on the Vcc track.

    Otherwise everything seems easy to understand and execute. For the inductor L5, does it matter what side I cut? You sai left hand side: looking at the PCB straight I suppose?

    thx...

  2. The Fokker Dr.1 only has one set of ailerons, on the upper wing: It was the Sopwith Triplane that had ailerons on all 3 wings. As the Dr.1 only has one of the wings 'active', you could use the conventional RC aileron control method of either 1 centrally-mounted servo with control rods running through the wing ribs to 90-degree bellcranks to operate the ailerons, or 2 slim 'wing' servos fitted in the wings to operate each aileron directly. You should only need a 4-channel radio (throttle, elevator, rudder, ailerons), or possibly 5 if you want a switch channel to operate a sound/light unit for the guns. You will definitely need rudder control - rudder and elevator are the 2 most basic controls for flight (they were the only controls on the first RC planes). Even if you use aileron banking to turn the aircraft, you have to apply rudder at the same time to stop the plane losing height in the turn. Rudder is also essential to keep the plane running straight on takeoff and landing. NiCads aren't really used as a power source for electric planes these days - they usually use LiPo packs and brushless motors due to the lighter weight (LiPo has a higher energy capacity for a given weight compared ot NiCd/NiMh) and more efficient power delivery. A BEC (battery eliminator circuit) steps down and regulates the voltage from the drive battery to a constant 5 or 6V so you can power the receiver and servos from the main drive battery You can either get a standalone BEC, or some aircraft ESCs have them built in (as they are with most car ESCs). Some aircraft modellers are still a bit suspicious of using BECs in planes and prefer the added safety a keeping a separate receiver pack - if the drive battery 'dumps' in flight and you lose power to the engine, you would still have power to the receiver and servos to make a controlled glide to land. The other important thing to consider when flying model aircraft is insurance - a 1/10th scale wooden aircraft with a powerful brushless motor swinging a big prop can cause serious damage to property or injury to people in the event of a crash. It you aren't already a member and don't fancy organising you own third-part public liability insurance, it's highly recommended that you join the British Model Flying Assocation (usually via joining an affiliated flying club), and you would then be covered under their insurance scheme: http://www.bmfa.org/.../insurance.html
  3. The same radio (Core RC is a brand owned by Schumacher) is also sold in the UK branded as the Tamco TAC330 (distributed by Amerang) and Etronix Pulse EX3GPro (distributed by CML). The Etronix version is available in both a stick and pistol-grip versions, and the pistol-grip version is also sold as the HobbyKing HK310/GM Racing (Graupner) XG6i/Robitronic TL-3C/Venom V3RT/Modelcraft (Conrad) MC30. The case of the pistol-grip version looks to have been 'inspired' by the Sanwa MX3. The OEM manufacturer for the radio is Xinyi/HiSKY (Guangzhou Chiyuan Electronic Co., Ltd, China) http://www.tradeeasy...2/selling-leads http://www.chiyuan.n...llClass=&page=1 The pistol-grip version is the CY-310. The stick version (CY-330) uses the same innards but built into the case of the CY-200 model, presumably created for markets where stick radios are still popular (such as the UK). The OEM version of the receiver is the XY3000 - some of the rebrands have kept this number (Robitronic), or modified it slightly (Hobbyking HK3000). The original version of the pistol-grip radio also appears unbranded as the 'N4-Q'. There are 3 versions of this model - the original 40MHz FM model, a 2.4GHz DSSS (non-frequency-hopping) version, and the current 2.4GHz FHSS (frequency hopping) version, The stick version appears unbranded as the 'N3-S'. some the rebranded models (Etronix, for example) were originally the DSSS versions and were later replaced by the FHSS versions (but with the same model number!). The DSSS and FHSS TXes and RXes are unfortunately mutually incompatible. The lower-spec pistol TX models (CY-220 and CY-300) and the receivers are also found in a lot of RTR car sets branded as the manufacturer's own products (OFNA/Hobao and Great Vigor, for example). I have also seen this lower-spec TX sold on it's own packaged with a XY3000 receiver as the Intech/Power Racing/Etronix CY300 If you find any 2.4GHz 3-channel receivers from the above brands they will probably work with the Code radio as well. If it's one of the unbranded 2.4GHz receivers to make sure it's the FHSS version.
  4. It's possible that the blue/purple wire might be a 'centre tap' from the battery pack, to provide 4.8 or 6V to the receiver PCB (i.e. a cheap way to avoid having to include a BEC circuit). The only way to find out for sure is to put a voltmeter between the black and blue wires and black and red wires.
  5. As I explained above, as it's been built around a 2.4GHz RF module it can only use PPM modulation, which limits it to 8 channels. The large piece of heatshrink on the antenna is a cover - unlike your Futaba antennas which are just coax cable with the 1/4 wave section of the centre core exposed at the end as the antenna, the 'lump' at the end of the Turnigy antenna is a 'sleeved dipole'. The coax will be threaded through a plastic sleeve, with the 1/4 wave centre core going straight through it and the outer braid (or a wire connected to it) bent back over the side of the tube. The heatshrink over the top is to keep it all in place. The effect is to try and get better reception sensitivity from a single coax antenna. This is Flysky/Turnigy's solution at trying to give their receiver some kind of antenna diversity without totally redesigning it. The very early V1 FlySky systems only had a single antenna (as is seen on most 2.4GHz surface and short-range 'park flyer' receivers), and had reception problems when used in aircraft as a result (on top of the interference problems the V1 system had due to not having frequency hopping). Most other 2.4GHz aircraft receivers have radio sections designed to use 2 antennas to give better reception at whatever orientation the receiver is to the transmitter (this is known as antenna diversity). To combat this problem quickly, Flysky simply added a second radio section into the same case (known as a 'satellite' receiver) .See the pic below - the V1 receiver is on the left with the tacked-on satellite PCB, and the V2 is on the right: The V2 FlySky receiver's digital section design has been modified to implement frequency hopping, but the radio section designed around a single antenna has been retained. However, to reduce costs they have removed the satellite radio section, and added the screened dipole antenna as a cheaper alternative solution.
  6. It was very successful. Delta had been one of the big names in 1/8th onroad racing since the late 1960s, and Art Carbonell was their star driver, wining numerous championships. Towards the end of the 70s 1/12th onroad was becoming more popular, so Delta started looking at producting a car to compete in that class (their first design, the Phaser, was an upgrade kit for the then-dominant Associated RC12E). Delta signed up Kevin Orton to assist in this effort (he already had a reputation for innovative ideas in the 1/12th racng scene). Kevin's first big improvement was introducing the t-bar and oil damper suspension system for the rear motor pod on the Super Phaser: This then went on to be universally adopted by everyone else, and is still the template for current pan car designs. Art Carbonell won the 1982 1/12th Modified World Championship with the Super Phaser, but he was still using a resistor-based speed controller at the time (the one to have then was called the 'Work-Rite', which used a bank of 8 resistors). Kevin came up with a clever modification for the throttle stick on the team's radios - a switch that moved the servo arm just past the upper limit of it's throw. This was turned on before putting the car on the grid and the stick was pushed full forward. When the race started the switch was turned off and you got instant full throttle off the line without having to wait for the servo to move it's full throw (similar to what a lot of full-size sports cars can do now with full-throttle starts), When the AutoDrive ESC was introduced though, the MSC became obsolete in racing. Orton also developed the technique of matching cells to build packs - before this racers usually brought a crate of packs to each event, using a new pack for each race. The Delta factory drivers with their matched cell packs would only bring 3 packs for an entire event. The other major development Orton came up with was peak detection charging, with Delta producing the first commercially-available chargers (hence why they became known as 'Delta Peak' - the name is a 'Hoover/Vacuum Cleaner' situation). Unfortunately, as seems to be the case with a lot of technically brilliant people, he was not a brilliant businessman. By all accounts he did not have very good interpersonal skills.either (which is one of the reasons Delta were happy for him to leave and set up Tekin) and it became apparent to his employees he had mental issues. He invested his money into property which did very well for him, so when running the company became too much (he ended up refusing to answer phone calls or orders from distributors) he wound it up and disappeared from the RC world. He has no connection to the current Team Tekin company.
  7. They seem to be OK, though at that price there will be an element of 'you get what you pay for'. A lot of people have commented on the variable build quality (Turnigy seem to be very keen on hot glue). They use the FlySky V2 FHSS 2.4GHz TX and RX modules, which although better than the original FlySky V1 system (which did not frequency-hop, and had some serious problems as a result), still has some drawbacks - the receivers have no built-in failsafes, and only have a single antenna so there is no antenna diversity. It's for these reasons that a lot of aircraft modellers have upgraded their 9Xs with FrSky DIY modules and receivers. Turnigy have made this more difficult in the V2 version of the transmitter though, as the TX module that clips in the back can't be fully removed - the antenna is hard-wired though to it via holes in the rear case and PCB, so it either has to be cut or desoldered off the TX module PCB to allow it to be removed. If you aren't going to use it for aircraft or nitro cars then these issues aren't really a problem - I went with the FrSky module to mod my MC10 as I wanted the failsafe for my 1/8th scale tank (I didn't want something weighing 70kgs going out of control). If you want to use it on Tamiya trucks with an MFU then having digital trims instead of analogue ones will make things awkward (though I see that some of the open firmware hacks have a mod to make the throttle trim buttons work like a slider - you would need to apply this to all of the trims). The only other thing is it's intended to be an aircraft radio, so the Y-axis on one of the sticks will be on a ratchet to be the throttle. If you want both sticks to centre in both axes, you will need to get the parts (coil spring and centring lever) from another 9X, or a radio that uses the same stick units. The '9 channel' thing is a bit of a misnomer as well - the 9X V2 can only ever use 8 channels as that's all the PPM signal through to the 2.4GHz TX module can carry. The V1 version of the transmitter had a fully removable TX module (the 2.4GHz antenna was on the back of the module). The radio had a telescopic antenna on the top of the case for use by 72 or 35MHz TX modules. When one of these modules was fitted, the radio could be switched from PPM to PCM encoding, and that is how the extra channel could be used (you needed their specific PCM receivers to decode the signal though). Unfortunately this facility was removed from the V2 version, as the 2.4Ghz module can't be fully removed, and the telescopic antenna was deleted in place of the fixed 2.4GHz one.
  8. The first ESCs for use in RC cars were made by Don McKay of Jerobee/JoMac in the mid-seventies, forming part of their 'Brick' integrated receiver/servo/ESC module. You can see the heatsink at the rear on this old ad picture: Also see this link where someone has gutted an original unit to fit modern gear into a on old Jerobee car: http://www.rc10talk....hp?f=33&t=29015 The JoMac design was relatively simple though, and although people started developing the idea a lot of drivers continued using MSCs, which were also still being developed (with braking resistors being added and so on). The first solid-state MOSFET-based ESC as we know them today (the Delta AutoDrive) was developed by Kevin Orton in 1981 while he was a driver for the Delta factory 1/12th onroad team (he then went on to form Tekin): The Mk1 version is on the left here, with the Mk2 on the right: Between the JoMac and AutoDrive speed controllers there were other designs around in the late 70s/early 80s for 1/12th onroad that were either simpler transistor designs or electro-mechanical (a mixture of transistors and relays used to switch between multiple speed steps - the Hilux E-MSC was similar to this except it used a servo to switch between the steps). It was around the early 80s when they first started appearing in 1/10th offroad (once it was possible to make them at least semi-waterproof). Acoms even made the AP35 specifically for the SRBs ( http://www.studio68....ult.asp?id=6400 ) though that was still an electro-mechanical design.
  9. Not quite - you will have to bind/link the new receiver with your transmitter (if you bought a transmitter-receiver combo for your first truck they come already linked together from the factory). It looks like the procedure for the 6EX is turn the transmitter on, then turn the receiver on and press the 'Set ID' button for 1 second. The receiver's LED should turn green when it's linked to the transmitter (it's on page 9 of the manual).
  10. The BEC (Battery Eliminator Circuit) was originally introduced to power the receiver and servos from the main battery pack, removing the need to use a separate 6V receiver pack on electric models. The packs were either 7.2 or 8.4V which was too high for the receivers and servos, so the BEC is a voltage regulator circuit that takes the input voltage from the battery pack and outputs a regulated 5 or 6V (though now they are available up to 12V to power high-torque servos). BECs originally started off as separate module you plugged into the receiver battery socket (The Hotshot came with one in the kit, as it had no space for a receiver pack), then started being built into receivers and ESCs. Nowadays with LiPo packs available in higher voltages, servos being available that can take more than 6V or need a high-current supply and micro receivers with no onboard BEC, external BEC modules have made a comeback. Electrically, there should be no reason why you couldn't use 2 BECs together in parallel - for instance, say the ESC's BEC could deliver 3A at 5V, and you plugged in an external BEC that had the same rating then theoretically you would have the ability to supply 6A at 5V. However, in real life this would only work if both the BEC circuits were of the same design and the same type. There are 2 methods to deliver a regulated voltage - a linear regulator circuit (mostly found in receivers) and a switched-mode regulator circuit (which is used in most ESCs). External BECs can be of either type. You can only use linear regulators in parallel, and then only if they have the same output voltage. Trying to use a linear and switched-mode or 2 switched-mode regulators in parallel is not a good idea at all, and it what BMT is referring to when he says about harmonics interfering with each other (which is what you get with 2 switched-mode regulators). They interfere with each other's load-detection circuitry which can cause them to go into overload, get hot and either be damaged or go into thermal shutdown (if they have been designed properly) BMT's advice about isolating the positive supply pin in the ESC's lead to the receiver is correct, and usually appears in ESC manuals to cover installs where they will be used with an external BEC.
  11. Just a bit more info for if you get a 4-channel stick radio for a truck or 3-speed and find the throttle axis of the left stick is on a ratchet instead of a self-centering spring (this is what my Techniplus 4 was set up as, even though it was meant for use with 3-speeds). That is the throttle setup that is commonly used on 4-channel aircraft radios (known as 'Mode 2' - 'Mode 1' is where the ratchet throttle is on the right stick), but it's not ideal for use with a 3-speed. Open up the back of the radio and look at the back of the left stick mechanism. The Y-axis (throttle) will have a flat metal spring screwed on that presses against a toothed surface on the back of the stick to provide the ratchet. The X-axis (gears) will have a plastic lever that presses against a cam on the stick axle, held against it by a small coil spring. This lever is what pulls the stick back to the centre. For a 3-speed, you want the throttle axis to self-centre, but it's not a problem having the gear axis on the ratchet (it stays in whatever gear position it's in when the throttle goes back to neutral). To do this, you just need to carefully unscrew and remove the ratchet spring, unhook the coil spring and lever from the X-axis and refit it on the Y-axis (tweezers or needle-nose pliers are usually required), and then screw the ratchet spring onto the X-axis. Of course, if you want to have it self-centering on both axes, you can move the ratchet spring over to the Y-axis of the right stick instead (which is the same as converting from 'Mode 2' to 'Mode 1' on an aircraft transmitter).
  12. <p><p> The one in the first link is a 72MHz aircraft radio, which you shouldn't be using in a surface vehicle unless you convert it to 2.4GHz using a DIY Module. The one in the second link is a 75MHz set, which is the surface frequency in the USA so that should be OK for you. As it seems you are in the US, I've also found this: http://www.ebay.com/...=item19d6e3290 from the same seller as the second radio. These are also these, which is the type of cheap 2.4GHz systems I was talking about - still analogue sticks and trims, but with a 2.4GHz RF section: http://www.ebay.com/...=item20b2c6341f It's still a 4 channel radio with analogue trims, it just has a 2.4GHz RF transmitter insteas of an old AM or FM one. Also, here is a link for a nice alloy shift gate to go on the throttle stick: http://www.ebay.com/...=item5897bfcba7
  13. I have recently added a new model to my showroom and made some typos in the description text. I click on 'edit model' and get the editor, correct the mistakes and then click on the 'update' button, but the changes to the text don't appear. Does it take some time before the updates appear? I'm on Win 7 and have tried it on IE8 and Firefox 16.0.2
  14. Well, my package has arrived from GiantShark, so it's time to stop waffling on about theory and actually do a conversion. The contents of the FrSky V8HT DIY Module package looks like this: There are 3 sets of leads coming out of the module - the aerial coax cable (with the gold-plated fitting on the end), the Bind button/Status LED lead (with the small PCB on the end) and the power and PPM input. This is the important one, and of you look closely one of the 3 wires in this lead has a heat-shrinked section at the end. This is the PPM input, and the heatshrink is covering a zener diode which has been soldered onto the end of the lead. This was an important modification suggested by the users on the RCGroups and GiantShark forums that protects the module's circuitry from being damaged by the PPM output generated by certain designs of transmitters. To install the module, you need to find somewhere to put the module, aerial, Bind/Status PCB and then solder up the 3 connections. The transmitter I chose was the Techniplus MkV, as it's my favourite one to use, and in my opinion probably the nicest-looking of the Acoms units I have. Firstly i looked for a location for the module. In my previous post about the MkV I said there wasn't much room in the case, and I found this to be true. A few temporary fittings using sticky tape showed that the best place to fit it where it didn't interfere with the stick mechanisms and gave easy cable routing was on the far right of the rear case, snugged up against the top of the battery compartment: Notice the heatshrink on the yellow wire - I have moved the zener diode further up the PPM input wire. I needed the connections to the PCB to be flexible, which wouldn't have been the case with the diode at the end. Next, I looked for a position for the aerial. As I wasn't keeping the 27MHz RF section functional, I decided to use the existing position, but this meant the case needed modification. The aerial support boss on top of the case is moulded as part of the front half of the case, but there is a thin section under the base which is split in half between the front and back of the case. I cut the boss off flush with the top of the case, then added a half-ring of ABS underneath to reinforce it and give a level surface for the aerial fitting to be bolted up to (this required the thin section on the rear half of the case cutting away to fit as well): The next thing was to find a position for the bind/status PCB. Some people mount these on the back of the transmitter case, but I wanted the LED somewhere where it was visible in use. As I wasn't keeping the 27MHz RF section functional, that meant the hole for the crystal socket was available. Again, a few trial fittings showed that this needed a bit of modifying. If the bind PCB was sandwiched between the hole and the radio PCB, it meant the radio PCB sat about 2mm too high and the case wouldn't fit back together, and the hole was too deep to use the bind button. I ended up cutting 2mm off the back of the hole for the crystal, which meant the bind button would end up flush with the front: The reinforcing webs were also trimmed to make room for the cable and to let the PCB sit squarely. The original PCB now fitted back in place, but when the button was pressed the bind/status PCB would push inwards as well. The solution to this was to put a blob of hot glue on the back of the PCB. One it cooled, it meant the crystal socket on the original PCB was pressing against the back of the bind/status PCB, holding it firmly in place: The 4-way cable fits through the gap between the original PCB and the bottom on the case, then folds upwards and runs in the gap between the solder side of the PCB and the battery box in the rear half of the case. it can be seen at the top of this picture: The power and PPM input cable can be seen above, running diagonally down to the PCB. This also folds at the bottom when the case is reassembled, which is why I didn't want to leave the zener diode at the end. The connections and cut tracks can be seen in more detail below: The black wire is the Ground, which was soldered to a convenient pad on the ground plane. The red wire is the power supply, and is soldered to the track that supplied power to the existing RF section. The yellow wire is the PPM input, which is soldered to the output of transistor Q4, as identified in my previous post. The 2 cuts isolate power from the existing RF section. In my original post on this radio I suggested 1 cut, and disconnecting one of the legs of inductor L4. The upper cut in the picture above does the same job as lifting the leg of L4, as I was not keeping the original RF section switchable. The aerial connector was then bolted in place and the 2 halves of the case were carefully put back together, taking care not to snag any of the new wiring. The transmitter was then powered up, and the flickering LED indicated that a valid PPM signal was being received by the module. I then connected up the 4-channel receiver to a battery pack and servo, and went through the bind procedure (very simple - power on the TX with the 'bind' button pressed, them power on the RX with the 'bind' button pressed, though you have to be careful not to have them too close together while doing so). Everything is now working OK: I have another TX module to use, which is for my Graupner MC10. That should be easier, as it has a trainer port connection on the PCB so the power and PPM signals are easily accessible.
  15. The Acoms AP401 Techniplus 4 is also suitable (if you can find one as it has been discontinued for a while too). If you are in Europe, look out for the Conrad Razor X4 - it's the same radio rebadged by Conrad. There are also lots of cheap new 2.4GHz twin-stick 4 channel radios with analogue trims around on ebay too thanks ot the foamie/park flyer market (I have just found 2 TX/RX sets on the first search page that were under £40). If you are really struggling to find one, another idea might be to get an old AM/FM 4 (or more) channel twin stick transmitter and convert it to 2.4GHz using a 'DIY' module. As it's going to be running 2.4GHz, it doesn't even need to be a surface radio to start with, and there are lots of cheap old 35MHz (or 72MHz in the USA) aircraft transmitters available that are suitable subjects for conversion.
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