i bought a used powertap, got new batteries for it today, everything works while on the bike. When I tried to "configure device", it says "no supported devices were found".
I am using a Mac, running 10.4.11. the cradle is the old 'serial' cable with the usb adapter.
I have tried al different ways of plugging in, , eg turn on poweragent, then put in usb cable then put in cpu, and a bunch of others.
I have java 2 installed, I have the powertap usb drivers downloaded.
I'm really frustrated, this stinks!
Any help is appreciated, thanks.

I don't think the old powertaps on serial cables work on macs. You should contact Saris directly they are very helpful. You might just need to get a USB cradle and update the firmware on the computer head.

Yep, you need the new USB cradle. Then I find PowerAgent is kind of weird on my new Powerbook, and I do have to do things in one particular order: (1) load up PA (2) then plug in the cradle, (3) click on my name on PA (4) then put the unit on the cradle and turn it on so it shows Host. If I mess with the order, it does not recognize the PT.

I think PA sucks, however, and since moved to the trial version of CyclingPeaks WKO+, which needs either the PC in Windows or you have to load Parallels, VM whatever or Bootcamp to boot your Mac into Windows. But WKO+ is so much better that I will use on my PC if I have to.

Is the unit all the way in the cradle? My cradle seems to have two detents: a first one that fooled me into thinking the unit was connected, and then the second and actual one where the leads slid onto the contacts after applying considerably more force. The other rookie mistake I made was not realizing I had to push a button and turn the unit on while in the cradle. The display needs to read, "Host" in order to be recognized by the laptop.

Well, at least you got the unit working on the bike. No Mac experience here, but it looks like the others have you covered.

Graphs. We need graphs

Thanks for the help. I am waiting on another set up that I got at a deal too good to refuse, so hopefully that will come with the newer cradle.
Waterrockets, the problem I Pmed you about, turned out to be my fault. The cadence attachment was stopping the unit from going all the way back by getting caught on the battery cover. Thanks for all your time and help.
I can't wait to see a graph myself, but I'm sure when I get to that point, I'll run into more problems.

It was pretty fun watching the watts last night, I dialled it up to 500 for a fast sprint.
I was putting out 200 watts at 144 bpm, my LT is 169, I will be seeing what kind of wattage I put out at that tonight.
I weigh a mer 135 soaking wet, so I hope my # are ok. and I don't suck completely.
This could be the beginning of a beautiful love/hate relationship between me and my PT, haha.

Yeah, I found it very distracting for the first few rides. Then I got in the groove enough to do some testing, find the holes in my fitness, and start patching them.

If you have a Powertap, you absolutely need Cycling Peaks software. I wouldn't even bother trying to configure it to anything else.

I am sure I will get additional software, but for right now my computer is not recognizing the cradle, so until I get a new cradle I will hold off on the software.

I did do my first outside ride on it, it's a recovery week, so I just had to do 2x15 min intervals at LT. I still have to figure out how to set it for intervals, so I can see and record each separately, but for my second 15min interval, I averaged 276w. I weigh 135lbs, is there an equation for figuring out watts per kg?
Or anywhere to find out howbad/good I am?
I am currently only cat4, I'd just like to know how I compare.

I found out my watts per kg at LT, which I can currently hold for 45 min, I am putting out 4.5w/kg.
I think that's alright for the end of my second base.

Yes, take the number of watts you put out and divide it by the number of kg you weigh

While I am enjoying WKO+ immensely, and highly recommend it to anyone with a power meter, you don't need it to get started. The PowerAgent software is adequate to monitor your performance and make training plan adjustments. I made huge fitness leaps before I got WKO+, just using PowerAgent.

WKO+ is a lot better on so many levels, but PowerAgent works well for what it is.

Cycling Peaks does not work on a Mac out of the box.