Mortymore

Lets observe the 1st schematic, since C1 and C2 works as reference (0v) of the other when one has 9v, I see that it would only be possible to power the 2 secondary receivers alternatively, i.e., when the upper one is powered because C1 has 9v to the GND reference, then C2 has to have 0v, meaning, the same as the GND reference, and so the lower receiver is not powered at that moment. If the inner lines of the primary receiver where switched, by a reverse command, then C1 goes to 0v, and C2 to 9v, powering the lower secondary receiver, and shutting down the upper one. Hope I made myself clear. I don't know also if that's what you are expecting to achieve. Cumps

I agree. Thought I never did any experimentation, just looking to the schematic of the 8884, you can see that an 8884 receiver only gets the regular power from the outer lines of the cable, and inner control lines are not connected. If they were somehow, then it would be possible that you could activate the second receiver, only when the first one enabled it. But the receivers pass the input voltage directly to the outputs, through the outer lines, and that's why that cascading receivers is nothing more than an "expensive cable extension", as Milan called it. Cumps

Well.. for what I've read here and there, the Excavator 8043 is taking care of the M-motors without needing any extra help. Now I don't know if I laugh of the joke, or should cry I don't see any problems by adding 2 receivers in parallel to power one motor. That same motor if was running directly from a battery box would draw at most the same current, and I don't see how that can shorten the motors life. I mean... it's not possible to make some amount of current flow through how many receivers you want, that the battery box can't provide. Cumps

That makes sense, since the dual channel H-bridge motor driver LB1836 that's responsible on the receiver 8884 for running the motors has a 1A current limit, and a XL motor 8882 may well draw instantly more than that at start-up, if the power supplied provides so, giving the motor 2 channels, each from 2 receivers, is allowing it to draw a maximum current of 2A. Then, when the motor is running normally, if it only draws 200mA...600mA... there's no difference if its power is provided trough 1 or 2 receivers, because only one was perfectly capable of keep him running at that speed. But the guy of this video is nuts for reversing the output of the receiver, since is making a short circuit and serious damage could occur. I believe that has LEGO provided current limit protection on the 8881 battery box, the same may be true for the 8878 battery box, or else it could have ended up dead. Cumps

Back to the 8884 IR receiver, I left you with the latest images of mass destruction. A primary hand made schematic that I hope it has no errors The components marked on the schematic with a cross over them, have their place on de board, but they were not assemble there. Note: Observe that almost every pin of the mistery chip (Alpha) as a connection with a test point (TPxx) on the board. BrickShelf (after moderation): http://www.brickshelf.com/cgi-bin/gallery.cgi?f=442112 Cumps PS: Schematic image was replaced because a correction was done. Any corrections or suggestions are welcome.

I agree. And makes sense to me since the datasheet of the motor controller LB1836says that the maximum ground pin flow-out current is 1A, being that the common terminal for both outputs, the sum of the current provided by both outputs must be balanced in order not to surpass that 1A or it would kill the motor controller. The datasheet says also that the LB1836 has the following protections: - Spark killer diodes built in (killing sudden raise of voltage, for instance when a motor starts, suddenly reverses, or stops) - Thermal shutdown circuit built in (when there's to much current being drain from the controller, making it hot, this could act as follows: lowering voltage -> forcing the current to drop -> drop temperature; or ultimately completely shutting down the controller until it cools down) So with all this gathered info I conclude that the battery power box 8881 don't limit current to 800mA. That said, if 1 or more motors are connected trough the receiver 8884, their total current provided should see a limit of approximately 1A. If those 1 or more motors are connected directly to the battery box 8881, depending on the batteries used, they should see the current limit at a maximum of 1.4~1.5A cumps

It's always a pleasure to do something for the community. The promised video It was hard to this one, because I had the camera in one hand, and at the same time had to push buttons, stall motors, pay attention to what is going on, and my daughter buzzing in my ear... Hope the video and the explanations helps somehow. cumps

Last night I was... well... experimenting again. Again, took some photos and made a video, but I haven't work out the video yet. My idea to test how far the battery box supplies current was, instead of power it with batteries, I soldered a couple a wires to provide power through an external lab power supply. This power supply has voltage and current regulations, so I started the test in a safe zone, limiting the output current to about 1.2A that I already have seen come out from the 8881 battery box with alkaline batteries on it. When I stalled the 2 motors 8882 and 8883 connected to the battery box, the lab power supply went to his current limit, and voltage start do drop, meaning that the battery box was letting all the current go through. When I raised the current limit to about 2A, the lab supply did not limit the current, but the battery box did, at around 1.5A (if I recall correctly) and the motors fast lose power, because it was notorious to me that they stop pushing my hand that was stalling them. When I set them free, they recover slowly, taking about 2...3 seconds to achieve normal speed again. This is not the most accurate way to test the current limit of the battery box, but was what I came up with. Suggestions are always welcome. When I have the video available I'll let you know. cumps

Good observation. If the batteries were reversed, current will flow through R2 and D2, once power ON, and that will be a short circuit with the diode D2 directly polarized and R2 with almost zero Ohm, doing nothing if it wasn't the fact that she is calibrated to fuse at a determined amount of current flowing. I will not test this, though. I already opened my 8881 battery box, and R2 has a slightly different inscription from the one that is seen on Philo website. His is "HL5L" (or maybe "HLSL" ). Mine is "H85L" (or "H8SL", the "5" could be an "S"... I gess). cumps

You're right. There's a resettable fuse inside the 8881 battery box, for current limit. Philo has shown that, and provided a schematic: http://www.philohome.com/alimservo/alimservo.htm I just don't know what's the current limit. But it could be tested. I just recall that once measured a peak current of 1260mA when playing with the 8265 front loader fully motorized. (photo / )cumps

Speaking of current... Fresh work. The setup The load for the 8884 receiver are 2 motors (8882 and 8883) in parallel, connected to just one output. With the 2 motors running freely, no more than 150mA was pulled. With the M motor 8883 stalled, the current went up at around 600mA. With the XL motor 8882 stalled, was around 800mA. With the 2 motor stalled, about 950mA. The maximum input current measured was 1A, and for the output 980mA. The batteries used were regular alkaline ones, and they're not fresh as can be seen from the voltage measured by meter at the left, so higher values for current may be achieved with fresh batteries, though the maximum current that the motor controller LB1863, allow through GND pin is 1A, so we are close here. I could do some tests with a regulated power supply instead of the batteries, but that wouldn't be a real scenario, and if unproper limit to current would be set at high level voltages, I might kill my receiver and it would be the end of the fun. Or maybe it could be a test for the thermal protection of LB1863 if done smoothly. I have something else left to do, but it will take some time. The partial (possible) schematic of the receiver. Cumps.

Yes, the chip allow you to have separate voltages for control (Vcc), and for H-bridges (Vs1 and Vs2), i.e, for motors if that's what you plug at the output. Trouble is that chip allow 10.5v max, for all kind of voltage supplys, Vcc or Vs. I'll do my homework as soon as possible. cumps EDIT: Vcc pins 1, 4 and 11 of the LB1863 are directly connected to Vcc line of the battery box, and GND pins 7 and 14 of the LB1863 are similarly connected to GND of the battery box, so the Vcc line on the motor controller IC has the same voltage as the battery box.

That was one thing that I checked and they are the same. The voltage provided by 100% duty cycle to the motor, is equal to the voltage provided by the battery box. No drop-out. I know it's best to put some notes on the video, but I hadn't find time to do it so far, but can be seen on it. cumps PS: About the LB1836, you may be right, but I found somewhere that there's a LB1836 listed as been made by Fugitsu, and the LM1836M always appears as being made by Sanyo.

Well... my curiosity was awaken, and I didn't sleep much. So far I manage to take some photos to the IR receiver 8884 board. http://www.brickshelf.com/cgi-bin/gallery.cgi?f=442112 It has a hidden controller under a drop of black epoxy And on the other side, has a dual channel H-bridge motor driver LB1836 I can´t find the datasheet for the exact reference LB1836. So far I only found the datasheet for LB1836M. Though they may work the same way, there's probably a slight difference on some specification, because the "M" should stand for something and I didn't find so far what it is, so be aware. One note for now. The LB1836M has max voltage supply of 10.5v and since some people here has applied more than that to the 8884 receiver, or the LB1836 has higher specs on this, or I still have work to do on finding what is the Vcc voltage for it at different supply voltages for the 8884, because is has to be somehow lowered by some of the extra components seen on board. Maybe I'll try to sketch a partial schematic, if I find the time and mood. Made also a video where some measurements can be seen. Devices attached to the 8884 receiver, and controlled by the 8879 remote, are regulated by PWM signals at a frequency of 1150Hz, and 7 forward, and 7 reverse, levels are provided, plus stop. Duty cycles of the PWM control signal are: 0%, 26.6, 38.9, 51.2, 63.0, 75.0, 87.2 and 100%. The corresponding DC level output, depends on the voltage supplied by the battery box, and at a level of 100% the output of the receiver 8884 has the same voltage level as the voltage supplied to him by the 8881 battery box. For now, that's all I could find. Suggestions or corrections are welcome, since part of the time spent on this I was probably more asleep than awaken. cumps PS: Square voltage AC from the PWM output of the 8884 receiver was measured accurately, because a TrueRMS meter with a passband of 20KHz was used. A traditional multimeter wasn't able to measure it correctly.

Try here for some pictures (though I think they are not valuable for what you need) http://www.brickshelf.com/cgi-bin/gallery.cgi?f=402995 See if you can find useful info here: http://www.philohome.com/pf/LEGO_Power_Functions_RC_v110.pdf I believe though, that the 8884 IR receiver has to have an internal power regulator, that despite the power supply (in acceptable levels), can keep the data signals on a desired level. But if you intend to use a voltage regulator, use a low dropout one to avoid run out the batteries fast, rather than the usual 7805. Now you have to consider the current need to supply the receiver, and I guess that will depend on what you have connected to it. cumps EDIT: Conchas brought to my attention that there's an earlier version of LEGO PF document, v1.20

Found this on youtube and loved it Lego - Io Carlo Non esiston case sufficientemente grandi da potere contenere tutte queste cianfrusaglie costruite, trasportate, comperate, rivendute non mi interessano telepromozioni di affaroni garantiti le vetrine di stilisti con le firme sui vestiti. Non mi interessano i consigli per gli acquisti io mi diverto ad ascoltare i miei dischi non mi interessano i bollini della spesa saranno anni che non vado più in chiesa. Dove son finiti tutti quei mattoni colorati quanti menti son cresciute, quanti sogni irrealizzati. Quando ero piccolo giorni interi trascorrevo a costruire con il lego ancora non sapevo a cosa stavo andando incontro Ora che sono diventato un adulto non mi riesco più a guardare allo specchio della televisione proprio me ne frego io mi diverto a costruire coll'ego. Dimmi cos'è che non va con me stesso dimmi qual è il meccanismo che è rotto dammi un ricambio perfetto così la smetto la smetto di riflettere, di ragionare, di cercare di capire, il senso delle cose Non mi interessano i consigli per gli acquisti io mi diverto ad ascoltare i miei dischi non mi interessano i bollini della spesa saranno anni che non vado più in chiesa

As a Technic lover, I sure wanted all sets, but since money don't stretch, I'm another one that may buy only the excavator 8043 this semester. This container truck 8052, though similar in aspect to the Cherry Piker 8292, is not mechanically as complex, and not as pretty IMO, but as a positive point on his side, the LA extra. Speaking of LA, though they have an internal clutch, I'm one of those that doesn't like the sound it makes when they reach their course limit, and in the 8052 case, they could have easily added that white clutch gear, as pointed in some previous posts here. The Hauler 8264 misses it too, but with the motor directly attached to the LA, that would be harder to do, but not in 8052 case where it's just a case of swapping gears. I was curious though, about the bucket raising mechanics on the 8052, so I de-assembled my 8292 Cherry Picker, and with some extra parts, and some improvise for those I still didn't have (mostly new Technic panels), I decided to build a kind of 8052, since LEGO as made the manual available (book_1, book_2) Cumps BS: http://www.brickshelf.com/cgi-bin/gallery.cgi?f=441236 Youtube:

E-motor comparison with other PF motors The following information about XL and M motors was collected from Philos website XL-Motor (8882): 40 N.cm / 220 rpm M-motor (8883): 11 N.cm / 405 rpm E-motor (W979670): 4.5 Ncm / 800 rpm cumps

Well... the list at Bricklink isn't correct either, since they list sets yet to be released (correction: I think some sets are actually freshly available but only in S@H UK), but observing it, I believe that Blakbird may have 2 more parts from the 8041 Race Truck, since I believe he has all Technic sets, and may not have those from other themes. cumps

First let me thank Blakbird for this great review. Next, I just want to say something about the comment on the 4L stop axle Actually, based on Peeron there is only 2 sets and a total of 6 of those 4L stop axles, but there's at least one parts list missing on Peeron for the set 8049 (Tractor with log loader) , and this set has 9 of those 4L stop axles. If I guess right, you sure have one 8049 set also, so you sure have more of those parts than you thought you had. Cumps PS: I don't know about the batteries lifetime, but about changing them, you can see how to in Sariel's video (@1.43 minutes). Thanks to him too.

2 images of the mobile crane 8053 Motorized B-model Cumps source: http://www.mytoys.de/LEGO-Technic-LEGO-8053-Technic-Mobiler-Kran/LEGO-Technic/LEGO/KID/de-mt.to.br01.21.11/2002573

According to what's written at TechnicBRICKs, those panels were painted. http://technicbricks.blogspot.com/2010/06/...murcielago.html Cumps

If I recall right, the walker of the picture above, only walk forward and backwards, and seems that Sternford is trying to do something a step forward, since he want that is walker be able to turn also. I can't be of much help here, but I wanted to add something to the information given by efferman about the parts he mentioned, to say that you can see how they can be assembled and work at Blakbird's Technicopedia, in this particular page: http://www.ericalbrecht.com/technic/1994.html The image I'm referring to is this: Good luck for your work. Cumps EDIT: Not that I've seen much, but here's the most complex gearbox I've seen so far (7 speed + rear), by Sheepo http://www.mocpages.com/moc.php/180863 And as you can see, it uses the parts suggested earlier

In Technic field I asked for: I´d like to see a LEGO Technic set of an hexapod like the John Deere walking forest machine or a "walking excavator" like Menzi Muck A91 John Deere hexapod Menzi Muck A91 (or A81) Look for videos at Youtube if you're interested in watch them in action. Cumps

1 - Do you buy sets like the Statue of Liberty, Eiffel Tower and Taj Mahal because you view them as amazing ‘parts packs’? Never bought one, because they're not cheap and I'm more interested in Technic though I like Creator as well. I suppose that if LEGO had an iconic building of my country I would buy it. 2 - Do you only buy specific models in the line because of individual appeal or do you collect the whole series because you appreciate the theme? I'm more interested in some specific sets, in some way because of the appeal, but mostly because of the parts and what I could do with them, or the improvements I could make to the set. 3 - What would you like to see as the next World Icon? Atomium 4 - What particular ultimate set beyond World Icons would you like to see? CERN. Maybe with fiber optics simulating a particle travelling along LHC 5 - The rest of your input not answered above! I´d like to see a LEGO Technic set of an hexapod like the John Deere forest walking machine or a "walking excavator" like Menzi Muck A91 I'd like to see in the City/Creator area, a really great set of a windmill or a lighthouse.