900 MHz wireless game controllers SHOULD NOT SUCK!

The BBQ Pit
1

Ever since I got my PlayStation three years ago, I have been waiting for a wireless controller that doesn’t suck. Well, as last night’s experimentation shows, we still aren’t there yet…

The first wireless remote controllers used infa-red. Essentially, the controller flashed a little blinky light (though not in the portion of the spectrum that humans can see) at the base unit, and that conveyed keypresses - whee. Problems with this approach were that any opaque object (a table, your finger, your roommate’s fat butt) that got between the controller and the base unit would block the signal and make you lose your game of Tekken 3. Also, any time you pointed the controller more than about 20 degrees off-angle from the base unit, the stupid light couldn’t cope, and you’d lose. I wasted $40 each time I tried one of these pieces of crap, and I tried three different models, each time about 9 months apart. I disassembled each of them afterwards and used a sledgehammer to crush the circuitry inside into little green pieces. (I am not one who tolerates shitty electronics well. Consequence of being an electrical-engineer wannabe who KNOWS you can do better.)

Very recently, the great white hope of wireless controllers came about: RF. “RF” stands for “radio frequency” and basically it means using radio waves to send keypresses between the controller and the console. RF is good because it slides through the human body like taco bell food and can also bounce off metal or stone objects. This means your roommate can masturbate like a crazed monkey between you and the TV and your four-hit combo will still come off flawlessly. However, since you can’t see the TV, you’ll whiff it and still lose your game of Tekken III.

However, like many things, RF is a lot cooler in theory than in reality. For starters, the FCC regulates the amount of power that can be transmitted via radio waves. 1 milli-watt is about it unless you get a license. At certain frequencies (or rather, in certain frequency ranges) you can get away with more, but those bands (particularly 900MHz) are already crowded with RF signals from cell phones, garage door openers, the next door kid’s remote control toy car, cordless phone handsets, etc, etc. What this all means is, for practical purposes, the radio waves emitted by wireless controllers are so weak and the air is so full of interfering signals, you might as well sledgehammer that RF controller and go back to cords. Which brings us to last night…

Several days previous, I had read a review of the MadCatz 900MHz wireless controller. The review said that the controller itself had a shitty D-pad and that the wireless capability was much less than the claimed 20 feet. “Bummer,” I thought to myself, and pretty much wrote off wireless controllers. Now, as it happens, the girlfriend and I had taken a break from bouts of multi-orgasmic hot monkey sex long enough to go to the vast wasteland that is known as the local shopping mall. GF decided she wanted to visit the Wizards of the Coast store - apparently her crack habit isn’t bad enough, she also likes collectable card games. While in there, I spotted a wireless controller by a company called “Pelican.” Pelican is headquartered in England, and only hardcore gamers would likely know them. I only know them because they make an excellent light-gun. The only one on the same level as the Konami GunCon.

I looked over the box. It was a 900MHz (of course), 30-ft (claimed) range controller. Dual-shock, so I could “play with my joysticks” (huh-huh, huh-huh) too. The d-pad wasn’t great, but it didn’t suck total rocks, and the controller was fairly comfy in my hands. It was $45. “Oh, what the hell,” I said. “If it turns out to suck, I can always either return it… or get the sledgehammer.” It was also compatable with either PS or PS2, so I figured I could keep it around even when I upgraded to PS2.

So I got it home and put the 4 AAA batteries into it. I tried it out first with the PlayStation’s CD player, which it worked passably with. But the range was terrible. I went downstairs and turned off my cell phone and computer monitor (both often sources of RF noise) and tried again. No discernable change. I still couldn’t sit 12 feet away and change tracks on the CD with it. No signal at all. I thought maybe the PlayStation being on the floor might be part of the problem, so I put it up on top of the TV. This is not so great, since TVs themselves generate some RF noise, but it was a slight improvement. I could now sit on the couch and change tracks - if I held the stupid thing just right and hammered the buttons multiple times.

Next up was some Soul Blade. A good thrash-em-up twitch fighter. If anything can test the mettle of a controller, this is it. Timing is key. Well, it worked fairly well if you sat less than 5 feet away. Great, tell me again why I shouldn’t just use a controller with a cord? Out to about 8 feet was very marginal. I’ve pretty decent at Soul Edge, but there’s not a lot you can do when your character refuses to swing their weapon. At least this controller doesn’t make your character do all sorts of crazy spazzy shit when you get out to the fringes of the range. I’ve seen wireless controllers do that. Finally, if you try and sit on the couch and play (12-15 feet), fuggedaboutit! No action whatsoever. You guys just sits there was the bastard computer executes the special move that makes him toss the opponent’s salad and come back for seconds.

Finally, I tried some GT2 in order to test out the analog functions. Same story as before, really. When the controls work, they work. Nice analog sticks on this thing, actually - I give Pelican full credit for that. But get more than about 6 feet away and you’re crashing and burning like Dale Earnheart.

So, I dubbed my latest wireless controller a(nother) pathetic fucking failure, and got out the screwdriver. And now I’m going to bore you with RF and EE engineer crap about what’s inside. You may want to skip this if you don’t care…

  • They’re using crappy lengths of copper wire as antennas. In the biz, this is known was an “omni-directional”, “quarter-wave”, “isotropic” or “marconi” antenna. A slightly different “half-wave” antenna would give them another 2db of signal strength, essentially for free - it would just take two more pieces of cheap, crappy wire. 2db more signal isn’t a lot, but it’d be SOMETHING. Also, high-gain directional antennas that would fit in the very limited space in the controller and boost the signal in the forward direction (while damping the radiation strength in the direction of your nuts) are available. They’re not cheap, but they’re not terribly expensive either. And even if they are, what the hell, I’m a power gamer - I’ll pay an extra $10 in order to have a controller that, you know, ACTUALLY WORKS.

  • The receiving antenna in the controller and the transmitting antenna in the receiver are set at right angles to each other. A marconi antenna has essentially no reception power if you send or receive the signal right at the point. That’s exactly what they’re doing here. So in addition to using weak, shitty antennas, they’re orienting them incorrectly, which will cause further degredation in the signal strength.

  • Inside the controller, the small RF circuit board has been grafted onto a standard PlayStation-type controller circuit board. So I suspect they didn’t do a lot of protocol design vis-a-vis making the controller and receiver talk. Which is a big mistake, given the notorious unrelaibility of the radio waves and the precise timing of the controller signals the PlayStation expects.

    Last and most damning, I didn’t see an RF amplifier chip on the RF board. This means they’re taking an extremely weak RF signal straight off the RF signal generator chip (an RF Monolothics 25-something) and shooting it unamplified straight out those crappy antennas. I’m surprised these things work at all with that setup! To my mind this is something like whispering at someone on the other side of a football field during the halftime show and expecting them to hear it. No wonder these things can’t work from more than 5 feet away.

Maybe in my copious free time (ha!) I’ll see if I can rig up a better set of antennas for these things (the omni->dipole conversion is unfortunately usually nontrivial) or see about hacking in an RF amp. I’ll be breaking FCC regulations by broadcasting too high-powered a signal, but WTF are they going to do? Come take away my controllers? Oh, boo-fucking-hoo! I hate the damn FCC anyway, censorious motherfuckers.

Well, enough of that. Suffice it to say, don’t waste your money on wireless controllers. Even with the advent of radio-signal based ones, they still suck moldy spooge out of the rotting cocks of the undead.[1]

…

But the thing that really pisses me off about all this is that there’s really nothing wrong with these things that more signal strength and a little more engineering couldn’t fix. But because they’re cheap bastards (read: shitty antennas) and because of the fucking FCC (read: major limits on signal strength) we are forever condemned to be bound by cords to our video games.
-Ben

[1] Band name!

2

Nice long post. Too bad I don’t believe a word of it.

Which of these doesn’t belong with the others?

  • Playstation 2
  • Tekken III
  • Your Roommate’s Fat Butt
  • Electrical Engineer Wannabe
  • Hardcore Gamers
  • Girlfriend
3

I know I know!!! It has to be Tekken III:)

As far as the rant goes, just hope that the thing doesen’t start really messing up.

4

Anybody who buys an English product and expects good electrical engineering at a reasonable price, deserves whatever he gets.

Not only is it an import, so you’re paying more, but it’s English, which means bad electricals. For example: Jaguars. When you consider that these beautiful cars all got much better-performing electronics when the company was bought by Ford – most Ford and Mercury owners have to replace their alternators 4 or more times over the life of their vehicle – you realize how shitty British electrical engineering is.

I strongly recommend you suffer in silence and use a wired controller, Chester.

5

All of this over a game controller?? Let’s hope you never get pissed at something that really means something in life.

6

Considering my last pit rant was about laundry, this is about par for the course. I tend to get worked up about the little things. Things that are so easy to do right, but are constantly done wrong due to the sheer, sheep-like stupidity of the human species.

Humanity makes me pro-nuclear.

Doesn’t matter; it gets the sledgehammer just as soon as I can desolder the RF boards. Maybe even before that.

Well if you don’t believe me about the girlfriend, fine and dandy. But if you don’t believe these controllers suck whale testicle, I’m apt to be a bit upset here! After all the time I wasted writing that rant…
And Cap’n Crude, you’re right about deserving what I got when I bought British electronics. But I’ll be damned if I shut up about it. ;]
-Ben

7

considering that whale testicles are inside the whale, and often weigh up to a ton, those seem to be QUITE the mouthful…

8

Should I even ask why saepiroth knows so much about whale testicles …?

Oh wait, I’m the one who discussed chimpanzee testicles on a final exam. Never mind, consider my previous comment rescinded. :smiley:

Regarding the OP, you should totally rework that crappidy-ass RF controller into something nifty. Your engineering friends will be amazed, your gaming friends will be jealous, and your girlfriend will give you more multi-orgasmic hot monkey sex, until the FCC sends a covert squad of their Men in Black to bust in your door and cap your l33t ass. Or maybe you should rework the bastard thing within FCC regulations and start your own company makin’ them.

9

Ah, I’m just having fun with you ModernRonin2. I’m a total gaming geek myself.

My pet peeve is the game developers who release games before the OBVIOUS bugs are addressed.

In the case of your controllers and my buggy games, one has to shake his head and wonder how the hell these things ever made it out the door.

10

Yeah, use your //\4[) 1337 5|<!11z and make some RF powered head-exploder/PS2 controller, and crack some FCC sp00k ass!! :slight_smile:

11

Well, I’m dubious about at least part of your rant, because 900 MHZ cordless phones work just fine at ranges of at least 75-100 feet (based on the one I have) with no noise. I’m guessing the bandwidth of a game controller is much lower than voice communication. So I don’t think there’s anything inherently wrong with the 900MHZ wavelength that some decent engineering couldn’t overcome.
I am willing to believe, given the respective sizes of the cordless phone and cordless game controller markets, that the decent engineering wasn’t done.

12

Man - that was one hell of a knowledgeable rant. But I’m sure that in the time it took you to write it, even I could have learned all about electronics and rebuilt the thing myself.

I’m still impressed, mark you. Good geek. Good!

pan

13

Well, first of all, I looked up the specs on the RF chip inside these things. The data sheets for the chip says these broadcast at a power of “70 dBuV/m” - the units on that are “decibel micro-volts per meter”. And I am STILL trying to figure out what the hell that means. The only unit I’m familiar with is straight up milliwatts or else dBm, which is a decibel ratio of milliwatts. I’m a wee bit annoyed RF Microdevices won’t tell me in non-marketing-speak what the power level of their chips is. Feh. It’s probably less than 1mW, meaning a range of 30 feet in totally ideal, zero-noise conditions. In the real world, especially with 900MHz, there’s NEVER such thing as zero noise. I also found some other RF chips that broadcast their signal at +3dBm (+2mW). But unfortunately they’re not pin-compatable with what’s already in there, so I can’t just swap chips. Damnit.

I also was trying to figure out more about how the controller and the receiver maintain synch. Well, it turns out to be pretty poor. I wanted to find out what would happen if the RF signal from the controller were suddenly cut off. For this I need some kind of shielded container that would block RF signals to put the controller in. Generally, the best way to do this is to make a small box out of metal window-screen mesh and ground it. But I didn’t want to go to all that trouble, and the hardware store was closed at this time of night anyway. So, I started casting about the apartment for a metal case of some sort. As it turns out, I happened to have several open-top metal containers in my kitchen. They’re round - I use them to make ramen sometimes. And one of them even had a cover for the top! Wheeee!

So I brought this pot and the cover out to the living room and threw the controller into it. To my amusement, as long as the pot was within about 2 feet of the receiver, the radio signals could bounce out of the pot and still be strong enough to keep the receiver in synch-lock. But, when I put the top on the pot, damping out all signal, it still took the receiver unit a full “five-one-thousand” count to turn off its “I have controller signal” LED. Which is pretty sorry - we’re talking about 900MHz here. As in, the carrier has a frequency of 900 million times a second. I would think 1/10th of a second without carrier signal would be more than adequate to conclude that the controller has turned off/gone out of range. I did some more experiments, like yanking the batteries out of the bottom of the controller while it was on, and it always took the receiver a good solid 5 seconds to “notice” the controller was off the air. Pretty sad. 5 seconds is an eternity in a fast fighting game or a hard-fought race in Gran Turismo.

So anyway, I’m already thinking about how I can desolder the RF board from this thing and make a better one myself. Maybe based on some RF chip that actually has a tolerable output power. Those 2mW RF Monolithics chips are looking pretty good. I’d need to do some antenna design, because I’ll be damned if I stick with the shitty “piece of wire” antennas already in there, but hell, I enjoy that kinda shit.

In the meantime, I’m thinking about ways I can still use these things. One thought I had was to put a ground plane beneath the existing antennas, but since they’re sitting at right angles to each other, it’d be hard to pull that off.

My other thought was sort of silly, but the more I thought about it more I thought it might make a good “in the meantime” solution. Basically, get a controller extension cord and plug one end into the PS and plug the receiver unit into the other end. This is sort of oxy-moronic at first - the whole point is no wires, right? But really, what I want is no wire attached to the controller. I can get an extension cord and put the receiver unit on the table in front of my couch, 2 feet away or so, and still use the wireless controller just fine. This should be good enough until I can get some better RF boards hacked up. Actually, I’ve been thinking about making my own sender/receiver RF units for PS controllers. I’ve already hacked out the controller synch serial protocol and thought about how it would work.

Heh, yeah, I’ll have time to putz around with RF circuitry. No, really! After an average hard 12 hours a day at work, I can still find the energy to do RF stuff. Yeah. Sure…

You got it. Most of those phones these days use frequency-hopping spread spectrum or other nifty techniques, and I think most of them broadcast at a power a fair bit higher than 1mW. Why don’t the controllers do this? It’s more expensive and the circuitry takes more space. I think Pelican just didn’t want to spend the money or do the engineering. (Well, to be slightly fair, a higher broadcast power would eat the batteries faster. But if your choices are to eat batteries faster, or have your product be essentially unusable, well…)
-Ben