[jraggio]

I have searched here and elsewhere, but have a few unanswered questions:

1. Pace car available in all modes or just the specific pace car mode?
   
2. Is there anything special about each of the modes or do they differ in just certain options are hidden in some of the modes?
   
3. Why do we need to select the track set? Is that simply to do the speed calculations and conversions to MPH? What happens once I buy more track expansions and add them to make the layout larger? Won't all that be off then?
   
4. I've seen folks discussing Magic ARC app.  Is it safe for cars and power station?  Seems to have good reviews so I'm curious what people here think of it.
   

Thanks.

[woodcote]

I’ll try and answer your questions…

1. Yes, just via the Pace Car mode (ARC Pro and ARC Air only).

2. No, the features in the various modes are the same - the differences are the ways of running the race (eg, endurance = length of race is specified time, Grand Prix = length in laps etc). Where features are not available is with the entry level ARC One (uses the app as lap counter + pit stops). Yellow flag is not available in ARC Air or the analogue mode of ARC Pro.

3. Yes, simply to calculate mph. And yes, it’s only accurate if you can find a layout listed that’s the same length as yours.

4. The Magic app was developed for ARC Pro using the ARC communication protocols, so is 100% safe and compatible. The Magic app builds on the Scalextric version, giving more user-customisable features, but with a more complex format and less slick GUI. I’ve looked at it here: https://slotracer.online/community/showt...p?tid=2811

I usually advise using the Scalextric app to get to know the ARC system - warts n all - and then enjoy digging deeper into the Magic app’s features, if you need more. I’m sure you’ve probably found it, but there is a guide to getting the most out of the Scalextric ARC app here: https://slotracer.online/arc-pro-guide/index.php

Hope that helps

[jraggio]

Hi again, Woodcote. Thanks for your reply and excellent guide. I posted a question over on Slot Forum regarding the math behind throttle profiles and calibration.

https://www.slotforum.com/threads/lookin...on.210933/

Trying to best understand what the graphs mean exactly and how they relate to calibrations, if at all. This stemmed from a weird bug I see in Magic where if I had a profile other than standard 50% the cars would fly off track at max speed on yellow flag!

[woodcote]

The calibration is a simple manual setting adjusted via the app screen and has nothing to do with the hand throttles. Ideally this calibration is a low speed where a specific car will get round your layout without stalling, but suitably slow to penalise running out of fuel or tyres. It is also the ‘yellow flag’ speed in the ARC Pro mode. It acts as maximum power setting in these specific circumstances. The process of calibration is shown very clearly in the ARC instruction booklet.

The need to manually set this calibration is because every car runs differently (even different examples of the same model) - variables such as motor characteristics, amount of friction in the drive train, wheel/tyre diameter, gear ratio, wheelbase etc all determine how much electrical power is required to get different cars round a lap in a similar time.

I take a look at calibration in the ARC Pro Guide here: https://slotracer.online/arc-pro-guide/classic.php

The throttle profiles are entirely different. This is when preset ‘curves’ in the app are used to modify the power data from the hand controller. These are all variations on a standard linear power delivery. That linear graph (the straight line) equates to a set amount of power delivered by the chip to the motor (vertical axis) per millimetre of trigger movement (horizontal axis). It’s what you expect from a traditional wire-wound resistor analogue controller. 

The variations offer the options of either a more gentle or steeper initial curve. These options will suit different types of cars and/or different driving styles. The ‘right’ one to use is the one that feels best for you driving a specific car - only testing and experimentation can decide which is for you.

The more gentle initial slope means more trigger movement is required for a small delivery of power. Then there’s a steeper middle section, continuing to the top. This might be good for non-mag racing or someone who likes ‘feathering’ the throttle.

Conversely, the steeper initial slope gets more power to the car with minimal throttle movement and then the slope is more gentle towards the maximum power. This can benefit cars with strong traction magnets or long-can motors - and drivers who have very precise throttle movement.

Such curves options are not unusual on high-end analogue (and some digital) controllers, although they are often more S-shaped and more customisable. The Magic app curves are more S-shaped and offer more options - this flexibility is clearly available within the ARC communication protocols.

Another variation common on high-end controllers is to squash the top of the curve - in ARC this is done by using the maximum speed setting. There are a number of presets available, plus the custom option of anything between 1 and 100%. I believe the height of the curve is lowered by squashing, rather than chopping. At least, that is what it feels like.

There’s more about the controller options in the ARC Pro Guide here: https://slotracer.online/arc-pro-guide/controllers.php

I hope that helps.

As for your bug - if it’s not listed as a known bug in the Magic App bug thread on SlotForum, then I suggest using the troubleshooting tips in the Guide to either hardstop and restart or delete and reinstall the app on your device: https://slotracer.online/arc-pro-guide/problems.php

[jraggio]

The calibration is a simple manual setting adjusted via the app screen and has nothing to do with the hand throttles. Ideally this calibration is a low speed where a specific car will get round your layout without stalling, but suitably slow to penalise running out of fuel or tyres. It is also the ‘yellow flag’ speed in the ARC Pro mode. It acts as maximum power setting in these specific circumstances. The process of calibration is shown very clearly in the ARC instruction booklet.

The need to manually set this calibration is because every car runs differently (even different examples of the same model) - variables such as motor characteristics, amount of friction in the drive train, wheel/tyre diameter, gear ratio, wheelbase etc all determine how much electrical power is required to get different cars round a lap in a similar time.

I take a look at calibration in the ARC Pro Guide here: https://slotracer.online/arc-pro-guide/classic.php

The throttle profiles are entirely different. This is when preset ‘curves’ in the app are used to modify the power data from the hand controller. These are all variations on a standard linear power delivery. That linear graph (the straight line) equates to a set amount of power delivered by the chip to the motor (vertical axis) per millimetre of trigger movement (horizontal axis). It’s what you expect from a traditional wire-wound resistor analogue controller. 

The variations offer the options of either a more gentle or steeper initial curve. These options will suit different types of cars and/or different driving styles. The ‘right’ one to use is the one that feels best for you driving a specific car - only testing and experimentation can decide which is for you.

The more gentle initial slope means more trigger movement is required for a small delivery of power. Then there’s a steeper middle section, continuing to the top. This might be good for non-mag racing or someone who likes ‘feathering’ the throttle.

Conversely, the steeper initial slope gets more power to the car with minimal throttle movement and then the slope is more gentle towards the maximum power. This can benefit cars with strong traction magnets or long-can motors - and drivers who have very precise throttle movement.

Such curves options are not unusual on high-end analogue (and some digital) controllers, although they are often more S-shaped and more customisable. The Magic app curves are more S-shaped and offer more options - this flexibility is clearly available within the ARC communication protocols.

Another variation common on high-end controllers is to squash the top of the curve - in ARC this is done by using the maximum speed setting. There are a number of presets available, plus the custom option of anything between 1 and 100%. I believe the height of the curve is lowered by squashing, rather than chopping. At least, that is what it feels like.

There’s more about the controller options in the ARC Pro Guide here: https://slotracer.online/arc-pro-guide/controllers.php

I hope that helps.

As for your bug - if it’s not listed as a known bug in the Magic App bug thread on SlotForum, then I suggest using the troubleshooting tips in the Guide to either hardstop and restart or delete and reinstall the app on your device: https://slotracer.online/arc-pro-guide/problems.php

Thanks for the details reply.  I wasn't sure if calibrated speed was a programmed max or some factor applied to the current trigger value somehow.  In Magi the car on yellow will go at the calibrated speed without input.  In ARC the car is controllable from 0 up to the calibrated max.