Modding the Cougar - ‹berCougar with Hall Sensors. 20th October 2002

Cougar World

HOTAS Cougar


Known Issues/ Mods




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Why mod?
It must seem odd to some people, that a section of the flight sim community would purchase a $300 controller, and then throw more money at it modifying its components. You'd think that wouldn't make sense, and you'd be right, if you didn't own a Cougar. Because you need to be a Cougar owner to experience and appreciate the Cougar and its community. Most Cougar owners are well aware that for $300, they've landed a bargain. A metal replica F-16 joystick and throttle offering unparallelled features and power, that heightens their simming experience, at a price considerably below break even that just doesn't make sense! Most will also be aware either from their own personal experiences, or from reading the forums, that the Cougar isn't perfect and aspects of it could be better. Enter the Cougar World community and some of its talented individuals! There are now mods discussed in Cougar World's Hardware forum to:

  • Remove the centre play.
  • Replace the pots with hall sensors.
  • Correct the speedbrake misalignment.
  • Remove the "double click" detent feel.
  • Reduce the spring tension.
  • Rotating the joystick hats for increased realism.
  • Alternatives to the rubber boot.
  • Rotation of the microstick.
  • Complete gimbal redesigns.
This is far from an exhaustive list and I've no doubt it will continue to grow!

What I want to do here is to share my experiences with two modifications from this list, that in my opinion, are ones you might want to seriously consider investing in. Before I begin, let me at this point state for the record that I paid full price for both these modifications, and that I have no financial interest in them whatsoever. They weren't freebies in swap for a favourable review!

The two modifications I want to discuss are:

  • Ian "III/JG11_IJ" Johnston's ‹berCougar: To remove lower axis and X axis centre play, and to reduce wear.
  • Ernie "CubPilot" Smith's Hall Sensor kits: To replace the joystick potentiometers with non contact Hall sensors, to remove spiking and increase precision.

My ‹berCougar with Hall sensors
‹berCougar with Hall sensors
Click to enlarge

Ian "III/JG11_IJ" Johnston's ‹berCougar
Understanding axis play

One of the first issues that some people experienced with their Cougar joysticks was play around the centre position. With some joysticks, you can physically wobble, and sometimes even slightly twist the stick at its centre position, before eliciting an axis response from it. The amount of play, if present, is very variable between different sticks, matched by a wide variation in user opinions as to whether it is noticeable and significant in flight. I personally never found it noticeable in flight, as I'm generally not very conscious of the position of my stick in combat. However bizarelly it was something I noticed more and was bothered by in Windows, but that's just me! Anyway, I'm not going to get into that debate here in this article - that's what the CW forums are for!

The cause of this particular type of play is, at its basic level, due to dimensional differences between the cast and machined components making up the gimbal system. There is an excellent document written by Guillaume "Dimebug" Leleve that discusses the 3 types of play that can be encountered with the Cougar:
  • The Lower axis play
  • The X axis play (specific to the X axis)
  • The spring play (can appear on both X and Y axes)
I highly recommend that you download it from Cougar World's Unsupported Files page and read it. With my Cougars, the spring play was zero, the X axis play was relatively minor but present and the Lower axis play was definitely the major culprit. After having read the article, and having seen that the lower axis play could in theory increase in time due to the differences in hardness between the materials present, I instigated the cheap and cheerful fix described in the article. In fact the photographs in the article are of the Cougar I modified.

The fix worked very well - but within a few months, it wasn't holding up. The play started to return. Thankfully within that time, Ian "III/JG11_IJ" Johnston started up the *Mods and Tweaks* thread and the ‹berCougar evolved!

What is the ‹berCougar?

The ‹berCougar, so named after a certain delighted German received his modded Cougar from Ian, sets about to remove the Lower axis play and the X axis play, and reduce future wear within the gimbals. This is achieved by re-machining the gimbals to much tighter tolerances with brass surfaces and roller bearings. By the way, it doesn't matter how much wear you currently have with your gimbals, as Ian replaces all the wear surfaces.

After seeing the excellent photographs of the ‹berCougar on Terrapin's site, I contacted Ian directly requesting information on what was required and what the costs involved were. Initially I was a little shocked at the price, until I realised I had been quoted in Australian dollars rather than US dollars - doh! After converting the cost at this site to a very respectable figure, I removed the gimbals from 3 of my Cougars following Ian's excellent instructions, and within an hour they were packaged up and in the post to Australia for modding.

I think it took about 2 weeks for the round trip using ordinary airmail - quite remarkable - and I was delighted with the work Ian had done on my gimbals. In no time at all, I'd got them back into my Cougars, and it was time to test them out.

Testing the ‹berCougar

I've been sitting here for the last hour trying to think how I'm going to pad this out into a whole paragraph, but I don't think there's any glamorous way of stating the obvious:

I have 3 Cougars with zero centre play.

Nothing. Zilch. Not a bit. How's the weather in your part of the World? I mean what else can I say? I have thrashed this stick around in my attempts to stay alive and score the odd kill in IL2, and I still have nothing. I almost miss being able to waggle it a bit in Windows. It just sits there, perfectly upright, motionless, and if I push it in one direction, it immediately engages a spring and generates axes values. And it does this for every direction I push it in. The ‹berCougar does exactly what I expected of it - it removes the Lower axis play and the X axis play, and in the months that I've been flying with it, there has been no change in that situation. Perfect.

I'm trying desperately to find some problems with the ‹berCougar to try and present a balanced review, but I'm struggling. Maybe I should add that when you first use an ‹berCougar, the Y axis is sticky at its extremes, but in a short time with some grease, the surfaces mate to leave a perfectly smooth travel. So that's not really a problem. Maybe I could add that an ‹berCougar feels stiffer or tighter than one with wear, so if you're after a lighter feel to your stick, you may prefer a Cougar with wear that benefits from less friction within the gimbal system. I've got one Cougar like that and it is easier to move around and has a lighter feel to it, although that's also because its springs have seen more action as well. However for all my sims including IL2, I only use my ‹berCougar. Maybe you only have one Cougar and you'd like to wait to see if someone is likely to produce commercially a completely different gimbal system, like the "Evenstrain mod." This is in fact the reason why I haven't ‹berised my last Cougar, as it is destined for some experimental work in the future under my dentist's drills ;) I guess the only real downside with the ‹berCougar is that you have to send off your gimbals to Ian, so if you have just the one Cougar, it could get frustrating not having a Cougar to fly with. Perhaps now is the time to buy that backup you've had your eye on ;)

I think it's fairly obvious - I'm struggling to find a balancing argument as to why you shouldn't mod your Cougar in this way.

In conclusion

Even though the centre play never really bothered me in flight, my recommendation to those bothered by centre play or concerned with future wear remains:

Get the ‹berCougar mod whilst you're able to!

It feels robust, it exudes quality and there's no doubt in my mind that it will add years to your precious Cougar.

Ernie "CubPilot" Smith's Hall Sensor kits
Those damned pots again!

Anyone who's owned and had much stick time with Thrustmaster's older controller, the F-22 PRO, will know only to well of the problems with the pots. It's one of the longest sections in my original TM FAQ - how to strip down and maintain those pots, and it's a frequently visited section in the Cougar hardware FAQ as well. You'd think therefore that in choosing the pots for the Cougar, time and resources would have been thrown at this cheap and yet critical component, so that TM could finally shed itself of one downside to its reputation. Alas, although in my experience the Cougar pots out of the box have fared better than the F-22 pots, they are still prone to developing spiking later. Hats off to TM for at least making their replacement so very much easier in the Cougar compared to the F-22 PRO, and as the mechanism for supplying spares is put into place, it's not the end of the world. However the fact remains for many of us, we want to be rid of this issue once and for all. Whilst I don't mind spending time away from flying developing and tweaking my joystick files, I really don't want to be using that time maintaining my Cougar.

Step forward please one Ernie "CubPilot" Smith!

A thread in the hardware forum

One day, whilst doing my regular sweep of the forums, a particular thread in the Cougar World Hardware forum had been started which immediately caught my attention - the Upgrade to "Cougar+ HS" kit available thread. What Ernie had achieved was to locate some suitable hall sensors, develop a bracket to facilitate their simple fitting into a Cougar to replace the pots, and put it all together as a kit. I fired an e-mail off to Ernie straight away, with my credit card in hand, offering to help test out these babies with the firmware and software in development. Before we go any further, let's familiarise ourselves with what a hall sensor is.

What is a Hall sensor

Ernie has put together a page entitled "What is the Hall Effect, and what can it mean for my Cougar?" on his site detailing everything you'd probably want to know about hall sensors. From our point of view, all that is important to take on board at this stage from that page is:

  • A hall sensor can be used to replace each pot in the joystick.
  • The hall sensor is contactless and hence its performance shouldn't degrade. This should equate to a spiking free, maintenance free solution to the pot issue.

The Hall Sensor kit

Unlike the ‹berCougar mod which has been around for some time, the Hall Sensor kit that I tested was one sold for beta testing before commercial release. As such, it should be noted that this is in effect a beta test report, based on around 3 weeks of using the hall sensors. Let's get going then.

Hall sensor in mounting bracket and the pot it replaces
Hall sensor in mounting bracket and the pot it replaces
Click to enlarge

Each kit contains 2 hall sensors in mounting brackets, to replace directly the Cougar joystick's X and Y axis pots, and some heat shrink tubing to protect the soldered wires. As you can see from the photograph above, the body of the hall sensors are much larger than the pots they replace, but that's no problem as there's plenty of room within the Cougar for them - see the photograph at the top of this page to see them mounted in my Cougar. The pots are connected to the main circuit board by 3 wires crimped into a connector. At the time of writing, Ernie is investigating where to acquire these connectors and crimping kits from. For my kit, I removed the pots with wires and connectors from my Cougar, cut through the wires to remove the pot, and soldered them to the hall sensors. If you're comfortable with soldering some wires together, then this should be no big deal for you whilst Ernie sources the connectors. One important point to make here is that the hall sensors will be damaged if you solder the wires the wrong way round, and therefore Ernie's instructions on this must be followed to the letter! You have been warned. Unlike the ‹berCougar mod, one advantage with this kit is that you can continue using your Cougar until the sensor kits arrive.

When my kit arrived, unfortunately the courier must have placed 10 Cougars on top of the box it was in, and the bracket arm was bent so it was no longer at right angles. You can see this clearly in this photo. The bent bracket This had an interesting effect when installing it - the autocalibration kept losing full range from one of the axes, and when I tightened up the mounting screws, I could see the hall sensor positioning being affected ever so slightly. Well I won't bore you with the whole story, but it was a simple matter to straighten out the bracket and all was good. This won't be an issue by the way with your sensors as the packaging has been changed to prevent this from occurring in future. What this did highlight though was how sensitive a hall sensor is to positioning, because the bent bracket slightly affected the angle of the sensor. I spent a couple of days trying different positioning for curiosity's sake, as the design of the bracket allows repositioning of the hall sensor within the bracket, to offset any variation there may be in the gimbal dimensions. Anyway, to cut a long story short, it was no problem mounting the 2 hall sensors, connecting them up to the circuit board and starting some serious testing. I should point out that since mounting them, I haven't needed to remove/adjust them in any way. By the way it doesn't matter whether you've modded your Cougar with Ian's ‹berCougar mod or not, the Hall sensor kit will fit both perfectly.


Anybody here remember what it was like adding the digital chips to an F-22 PRO and seeing the rock solid performance in Foxy's Joystick Analyser? Well if you want to experience that joy again, get yourself some hall sensors. These hall sensors people are good. In fact they are very good! The signal from my Cougar is precise, reliable, reproducible and spike-free. And I have put my Cougar through some hell to try and see whether that signal would degrade with serious joystick abuse. I even did an all-nighter dogfighting online in IL2 at the Hyperlobby and there has been no change in that perfect response analysing it closely in Foxy's Joystick Analyser.

But is it any better than a new Cougar pot? Well I lined up one of my other new Cougars beside the hall sensor modded Cougar for some side by side testing. And the answer I think is a subjective "Yes." It's close certainly, but the hall sensor seems to be easier to reproduce the high resolution capabilities of the Cougar and to maintain a steady signal when holding the Cougar at a given position. Where the comparison swings completely in the hall sensors direction is with a pot that has started to degrade. I have one such Cougar where the pots have seen 6 months of intermittent action, and the difference here is like night and day. They just can't hold up against the hall sensors at all. I really can't get over this exquisite precision! Now I was excited, and curious - I needed to see what these sensors were capable of and that meant some tests on different firmwares designed to push the Cougar to the limit. Let's bump up the Cougar resolution, turn down the filtering and see what happens. (Before you ask, no, there are no options for user control of these variables.) At 3,000 resolution, the response is flawless. The Cougar is easily able to distinguish 3,000 separate values from each of its joystick axes. At 4,000 - again flawless. Ok what the hell, this has got to be tried ... - up to 8,000 - oh yeah! Now getting to the point where I can't hold the Cougar still enough, as the sensors are now detecting slight vibrations in my arm. Perhaps I should be doing this without the springs in, but I can't really be bothered to disassemble the gimbals. I'm just staring at the analyser ... to see if it really is true. Ok - go back into the analyser code and increase its sampling rate and accuracy. And it's still the same. I wonder .... OK ... this I've got to try .... 16,000 .... Holy Crap !!! It's doing it, but now it's getting too difficult for me to hold the Cougar steady, and to get the right combination of filtering (to dampen down the vibrations) to move the Cougar to a position where I can always repeat the values. Unbelievable! Well, I've dropped it back down to 4,000 now as to be honest, you're not going to see any difference in a flight sim at these high resolutions, but from an exercise in precision, and a reflection on Mark's firmware's abilities, this is outstanding. Certainly I cannot get this from my Cougar with new pots - the signal requires too much filtering to attain the same stability and this results in too sluggish a response on changing axis direction that is unacceptable. Anyway - good fun!

Apart from some soldering for those ordering the first kits, there is one other disadvantage to the hall sensors. The X-axis is reversed. As I've stated before, do not even consider trying to fix this by reversing the positive (+) and ground (-) wires as you would with an ordinary resistive pot. If you do this, you'll destroy your sensor. Thankfully, it's very easy to counter though as the Cougar has several ways to reverse an axis for those receiving their hall sensors in the near future, and we can implement a fix for this with future releases of our software that will make this transparent and something you can forget about. So don't be surprised when you first install your sensor to see the X-axis reversed. Just open up the CCP, reverse the X-axis and hit apply.

In conclusion

I've got 4 Cougars, and only one hall sensor kit. That means I need to get hold of another three. I would therefore appreciate it if you'd all wait for me to order and receive my other 3 sensor kits before you place your orders. In the meantime continue to maintain your pots and enjoy your flying.

In other words ....

Get your order in! I think these will sell well, sell quickly and I think Ernie may end up with either a supply problem, or a "not enough hours in the day" problem! And if that means I'm not going to be able to get my other 3 kits in the near future I'm going to regret ever writing this review!

I'd like to take this opportunity to offer my sincerest condolences to Ernie for the complete loss of spare time he is now going to experience for the foreseeable future, as the Cougar claims one more victim. One day in the future I hope we all get to meet up so that our wives can bang our heads together over what is, at the end of the day, a joystick! In the meantime, would the next victim please make their way to the hardware forum ;)

Contact information
If you're interested in obtaining these Cougar mods, and want to find out about pricing and availability, you need to contact Ian and Ernie, so here are their contact details:

  • Ian "III/JG11_IJ" Johnston's ‹berCougar: E-mail. Forum thread.
  • Ernie "CubPilot" Smith's Hall Sensor kits: E-mail. Website. Installation instructions will be available on Ernie's site shortly, downloadable in Word and Acrobat formats. Forum thread.