RamJet-X Digital Speed Controller

[Perrotoro]

I picked up a RamJet-X Digital Long Cord Speed Controller. Though I'm an amateur home racer only at present, I do not feel any appreciable performance enhancements over the stock controllers. I was hoping for to notice more control-ability but basically it still feels somewhat like there's only slow/medium/fast throughout the range of motion of this controller. Guess I gotta step up to something more than this to play around with performance enhancements - or what?

[noddaz]

Wow. Sorry to hear that. I have used those and find that they are a tremendous improvement over stock.
Scott

[BRS Hobbies]

I find the stock Carrera DIGITAL controllers to offer very good control. I think the main reason for switching to an aftermarket one is some prefer the pistol grip style controller over a thumb style controller.

[b.yingling]

[Perrotoro]

Yep - stock magnets. I switched over to the less voltage and more scale-like speeds about two months ago. (As discussed in other posts.) Thus, I removed a ton of magnets from all cars - dang, I bet I removed $100 or more worth of magnets from about 45-50 cars - ha!

Anyway - I can't see appreciable range of throttling with the RamJet. The (30V 10A Adjustable Variable Digital DC Regulated) Power Supply shows 12.7V, and I read 11.58V with the digital multi-meter at all sections of the track as I have jumpers from the control unit to 3 different locations on the track.

[Perrotoro]

b.yingling and others - a little more info and a little more question: even though I measure 11.58 V to all sections of the track with the 3 jumpers, I notice one lane (say lane A) slows slightly in 2 locations where lane B does not. This occurs even if only one car is on the track - though with the 10amps, I still wouldn't expect more cars to be a factor.

I have every car set so that when my amateur home racers (including myself) race their 1st 2-minute heat, the cars are reasonable fast with premium tires and other basic tuning, but will not de-slot - at least 99% of the time. An autonomous car is set to race with them at a speed they can beat - if they manage the 3 crossover locations well. In the 2nd or 3rd heat, I'll up their speed with control unit such that they'll de-slot at several locations unless they manage their speed well too.

Point being, that maybe the noticeable controllability of the RamJet is reduced due to reduced Voltage and Speed Control setting??? But, I wouldn't think this explains the difference in lane A and B performance???

Enough info provided to form an opinion?

[BRS Hobbies]

I think it's a combination of lowering the track voltage and lowering the top speed on the control unit which is giving less noticeable throttle control steps. Basically, the higher the track voltage, the more variance in speed you will have at each controller throttle step. I can't really think of any easy solution, other than going back to using one traction magnet in the middle of the chassis so the cars can stay on the track at a higher speed setting.

[kidvoltage]

I would suspect either a bad connection on one or more of the track sections or perhaps the lane has become restricted somehow.

Slide a car through the "slow" sections and if you don't feel any resistance then check the track connection pins. Jumpers are wonderful but they can't fix every track issue. If you have extra track, it might be quicker to start with replacing the sections in question.

As for controllers, we also offer a spring tension setting, longer cables, optional short or long trigger and a complete selection of replacement parts should there be a parts failure. To date we've had one spring and one button failure in over 600 sold units. And the button failure was one that was dropped on the floor. However, if you feel your plunger unit is doing an adequate job, use it. At one time a COX thumb controller was the tool to have.

[b.yingling]

Couple things I'd recommend. Set the voltage back up to at least 14.8 (which should deliver about 13.5 to the track) and reduce the max speed of the cars by...reducing the max speed of the cars. I'm surprised you don't have trouble with lane changers firing too slowly and failing to open in time with <12 volts being delivered to the track.

Because of the way the CU sends data on the rails, and let's the car chip calculate final voltage delivery to the motor, reducing the top speed of the cars and leaving more voltage available will almost certainly *increase* the range of throttle response for those cars.

Your one bad lane has a particularly bad connection on one of the rails in that lane. Increasing your jumper count is the easiest/laziest way to fix it.

[Perrotoro]

Thanks again all!

I'm not terribly worried about the RamJet-X not having finer throttling capabilities for now - just a nice fun try for self-racing, tuning, etc. I think I'll hang with the lower voltage and try to find the weak track section and/or add jumpers to try to fix the Lane A issues.

I really like that the entire fleet presently completes the circuit within a few tenths of each other at this Voltage and Specific speed setting for each car. My junior and amateur racers can select any car need only worry about traffic and lane changes in the 1st couple of heats. And it's reasonably a fast pace with premium tires, standard tuning, and stock magnets - typically requiring de-throttling at the end of 3-straights and just before de-slotting in the curves.

At this lower voltage, nearly all cars are set at a 30-70% (10% = 1st light blinking, 20% = 1st light solid, 30% = 2nd light blinking, etc.) speed setting so that there's room to play. The two NSRs, three Scaleautos, and better Slot-its might only have a 20% speed setting currently, so increasing the voltage may put them at a speed setting below the range of the control unit. But if I can't find the weak lane connection or fix it with jumpers, I'll try upping the voltage.

[b.yingling]

I didn't recommend upping the voltage to fix the lane slow down- you fix that with jumpers or by finding the bad connections.

Raising the voltage and lowering the car's max speed settings will *increase* the range of throttle response.

I am surprised you have no lane changer issues if you are feeding them <12 volts.

[Perrotoro]

No lane changer issue at lower voltage.

I checked nearly every piece of track last night with the digital multi-meter - both lanes. All showed 11.58 to 11.62 volts. There was one location where from piece-to-piece, on one lane only, the voltage dropped from 11.62 to 11.58 - but it just doesn't seem .04 volts would have a noticeable impact on the cars speed. Regardless, I'll experiment with a jumper there.

[b.yingling]

Unfortunately, a multi-meter set to read voltage (unless it can simulate a load) is not a very good tool for finding poor connections on a slot car track. A great tool for finding them is a slot car (because it does create a load). Where does the car slow down? That's where your bad connections are.

You can have a connection so bad that the car will stop dead on the track and your multi-meter might only read .1 volt difference.