[RichG]

The problem is that from the controller socket you only have access to the input to the A/D and Gnd. Putting a variable resistor in series with this will enable you to increase Max Throttle, but as I said in the original post, you also increase Min Throttle. Cars begin to move at 0.3K so you don't get much scope.

Reducing Max Throttle for kids is best achieved by opening the controller and either physically reducing travel or by fitting a pot across the 5K resistor.

You post has however promoted a messy thought. The 1.8K resistor is connected between 5V & the Controller input. We have access to the controller input & we have access to 5V on the Aux port.

So some messy wiring would allow connection of the 15K across the 1.8K

I have to say that I don't like this solution it would need 6 plugs and sockets and a lot of wires.

Also a word of cauction. The 5V regulator output in the Powerbase has a surface mount 0.5 Amp fuse. Messing about with anything on the Aux Port can easily blow it. Of course I have never done this.

If your Powerbase has ever shown the symptom of backlight on but no display, this is probably what is wrong.

Richard

 

[Kambuk]

I was meaning remove the surface mount 1.8k resistor, drill some holes in the top of the unit for the top of the variable resistor to poke through and solder wires from the variable resistor to where the surface mount resistors were (tricky but doable with the right tools).

Kambuk.

 

[RichG]

If you are willing to drill holes etc,

then you can do most things.
Had been trying to keep the Powerbase intact and modify externally.

 

[mad727]

This topic has been idle for awhile so I don't know if this will reach anyone but i wanted to add a few neophyte comments. First wanted to thank Rich and everyone else for all of the great in depth topics. Great reading.
Second, even though I feel like an minority on this forum because I have SCX digital and not SSD, I was glad to read that throttles can have varying degrees of power. It was driving me crazy but i have 1 throttle (out of 7) that outputs so much more power then the others. I think for now I will just have to match it to the slowest car.
Third, SCX Digi does have the jr speed option built right into the control unit. It works amazigly well. Rich maybe you could borrow that idea for the ssd system and solve one of your issues, IMHO.
Though I imagine there might be some legal issues with that

Ps,
I'd love to see that poll again on who owned which set and from where. Might be cool to split it up between digital and analogue.

 

[RichG]

Hi, Thanks for the nice comments, glad someone appreciates the research.

I do not know the SCX system but am intrigued as to how one controller produces MORE

power than the others.

This implies that all SCX controllers are deliberately restricted

I sugest that someone that owns one takes it apart and make a few measurements. This should quickly reveal what the differences are and also the Jr speed mechanism.

Assuming that the SCX controllers have a variable resistor and that these feed A/D converters in the control unit (like SSD) then they have two choices for Jr speed control.

1) A simple additional resistor that is switched into circuit to restrict maximum power.

As an aside this requires the control works in conventional fashion, i.e. Max resistance is Min speed and Min resistance Max speed.

2) That it has an additional signal line which selects a different throttle map in the Control unit.

This would be nice but suspect unlikely

Perhaps someone has already analysed the SCX system, has anyone got a link

 

[mad727]

Hi Rich,
I haven't seen much written on the scx system compared to SSD or Carrera. Seems all the enginneers/programmers are SSD guys...

 

[sax0607]

Hi all , after recently purchasing a new power base version 1.5 , it came with two new controllers ( 4.9k), i found out how bad my other 6 controllers were (3.6k to 3.9ka) so I set about finding a cure and did !!! , i will try and explain and pic to follow.......... firstly soldered a 1.2K resistor in series with the slide pot at the low resistance end , and as stated in a previous post this causes slow creep when car is supposed to be stopped , but great top end speed !!! , so solve the creeping problem i decided the new 1.2k resistor needed to be nullified at stand still , to do this a contact point is made on the trigger that makes contact with the low resistance end of slide pot , the other end of this contact point goes to the other end of the new 1.2k resistor , and their we have a fully functional 4.9ka controller !! , if your not confused by know you are genius , seriously a pic tells a thousand words , i just hope it attaches correctly
sax

 

[RichG]

Good solution sax, i like it.

Has the new contact proved reliable?

This post answers another question. Did Scalextric choose to fix the 3F controller problem in the 1.5 Powerbase? Unfortunately as we can see the answer was no.

Down to the users again, well done sax.

 

[sax0607]

Thanks Rich , i hope this helps a few other users out , theirs nothing like a 30 cent fix !! , contact is good at the moment (100 odd laps ) but i can for see it getting dirty and causing the creep issue, so i will replace it with a positive acting miniature momentary on (normally open) switch tomorrow
sax

 

[Xlot]

Very ingenuous

Now, I hope I'm not being stupid : you needed to do this anyway, otherwise you'd have lost trigger braking - is this correct

Beppe

 

[RichG]

sax Just extending your idea.

If there is room for a switch in there, the solution could be implemented the other way round. Put the switch at the Max throttle end of the travel & have it switch the 1K2 resistor into circuit, or if it is easier a 5K resistor completely replacing the slider.

This would eliminate any slight jump as you come off Min throttle. That said your solution might be better as you will have more control at Max throttle.

Swich idea is good, post a pic when it's done.

 

[sax0607]

not sure about the dynamic braking ? didn't try it , the button brake still worked when I only had the 1.2k resistor in and no contact (i was using it to stop the car from creeping)
sax

 

[sax0607]

Minimum and low throttle is good , i expected a sudden instant rush of uncontrolable speed , but not so , i am happy lad , of to buy six switches in the morning....
sax

 

[RichG]

Dynamic Braking is a good point. This is separate from button Braking, and obviously we need to make sure it still works. You may also be able to solve another problem I have with some throttles, which is that they do not reliably return to a low enough resistance to give dynamic braking.

 

[shaunbmx]

Would love to see some pics when the problem is solved, and can you tell me what switches i would need to get as i am sure to get the wrong ones.

Looking forward to seeing the results.
Hope it works for you.

shaunbmx

 

[sax0607]

picked up switches today and fitted one ,simply fantastic result , the accuracy of the switching position is spot on.......... and can confirm ,all braking systems: , button, dynamic and combination of both work as intended

,heres a pic of the switch and location I placed it , if time permits tomorrow I will do one as Rich has suggested, with the 1.2k resistor on the max throttle end .
This system works well and is a cheap alternative to buying a new controller that may be up to scratch ,and i recommend it if you believe you have 3F controller issues

sax

 

[JoeT]

sax,
Fantastic work!
Thanks a ton.
Joe

 

[sax0607]

the switches are subminiture microswitch , they are sold by a company here in Australia called Jaycar @ $3.30 each AUD , I'm sure Radiospares or Farnell would have a similar switches in stock
sax

 

[RichG]

Great stuff sax. Could we have a picture of the completed final assembly. And any additional words it needs to enable others to make the same improvement.

 

[drummer]

great work that man!

Ive got a hand full of controllers I think need this treatment.

Originally we were using one of the software programs to check for full throttle 3F, but I never had much luck getting it to display the throttle data...

Is there a simple way of using a meter to measure controller performance?

Probably worth mentioning here that Professor Motor make a spring replacement for their controllers that fits (albeit tightly) the SSD controller.
Ive had 2 or 3 springs break now - another bugbear. The ProMotor ones feel great - I find many of the default springs are very strong results in midle finger muscle fatigue!!!