Where can I buy a cheap transponder? (Page 1 of 2)

Just rent from Lemons. It's a $100.00 a year subscription fee even if you did find a used one to buy. So really you would have to reliably do more than 2 races a year to break even. And with renting you don't have to worry about losing it, or forgetting to charge it, or forgetting to renew.

As far as I know AMB (MyLaps) will only transfer FLEX and X2 units to a new owner. And you'll want a Car unit specifically. And know they are sealed and the older ones batteries are pretty old by this point.

Just let Lemons deal with it.

You can still Register with Speedhive, or whatever they're calling it this week and download your laps because Roland loads up everything properly and you'll see your teams name and everything even with a rental.Unless you run with another organization that requires you to buy a transponder, or you race like 4 times or more a year reliably, it's just not worth buying.

Also FYI Lemons now uses X2 transponders so definitely get your own X2 bracket and install it on the car. That way you just pop the x-pnder on and strap it in. and they're only like $9 + Shipping.

Guildenstern is right...if you only do a couple races a year and aren't sure you're in for the longer haul, renting is easy and probably cheaper. 

If you're like us, we'll be running 6 races in our first year.  To avoid all the headaches of charging, losing, etc., we bought a direct power unit and did the 2 year subscription.  So our unit will pay for itself in the first year.  If we're still going strong, we'll probably renew the subscription for 5 years after that.

Certainty about racing and expected number of races is the whole key to your calculus. 

Oh, and to answer your original question, cheap transponders don't exist.  The pre-subscription used ones are pricey enough that you need to be sure you're in for 10 races for them to pay off.  Only other option is the new stuff.

Hope that helps confuse things even more.

Correct. I was thinking the 50 weeks of not racing. Where all the good losing things happens.

Sorry.  Didn't mention that we are also running another unnamed series.  Only 2 Lemons races annually in our neck of the woods.

Yup, this.

Watch ebay daily.  Some time one will pop up reasonably.

Also, google search for the model you want.  Sometimes will link to some forum where someone is selling.  Ours has paid for itself around 5 times already.

So I wen't down a related rabbit hole recently, as having to pay a yearly fee to use hardware you already have is absurd, especially when you don't get any new features or upgrades each year.

I reverse engineered nearly all of the MyLaps X2 transponder, down to the component level, with full schematics and part numbers. The goal was to research either re-implementing the transponder part or find a way to trick the transponder into staying "active" without paying the yearly fee. Ultimately I hit a reasonable wall and determined there was only one or two possible attacks, but neither were very good and had a low likelihood of working.

The sad part of this all is that 80% of the engineering and hardware inside the X2 transponder is basically there for DRM. The core transponder functionality and circuitry is ridiculously simple, and could be implemented stand-alone with <$5 in components (and retail for $50 with profit). Looking into the engineering behind the transponder it's clear that the main goal of the design was to protect people from "unlocking" or cloning the transponders. Even the "Direct Power" feature exists in hardware in all transponders, but it's only enabled through a secured/encrypted software flag.

The other disappointing thing about X2 is that it's marketed at least as a "next generation" transponder, but it doesn't actually do much different from the original TranX models, except implement a bunch of DRM. Reading the copy on their website I thought it may have been two-way and I could see my lap times on the X2's CAN bus, but none of that exists and MyLaps has no motivation to add any useful features for free.

I would like to get my hands on a TranX260, even if just to borrow one and probe it a little. Given the tech inside those older models and the year that they were designed, I expect that any security that they have (if any) would be much simpler to defeat and then replicate in custom (cheaper, DRM free) hardware. The RC drone racing and RC car racing guys have already reverse engineered those variants of transponders, so I'm confident it's possible with the 260. That's at least until MyLaps decides to end-of-life the older TranX models and force everyone to use the X2's.

Anyway, to answer your original question: For now if you do 3 or more races a year, just buy the X2 transponder and feed the ridiculous monopoly that is MyLaps. Otherwise just rent it and split the $50 between your drivers.

I have an MX model that you could tear apart to your heart's content.  Only difference between the 260/160/MX is the top speed they will register.

The unfortunate fact is, you’re not paying for the transponder, you’re paying for the “privilege” of being recognized by the Orbits system.

You could build a clone transponder, but at worst it will crash the timing and scoring equipment like the motocross one, and at best it will just be ignored by the decoder or the orbits client. Although more likely they won’t even accept your “transponder number” and tell you you need to rent one because your car can’t be put in the system.

Believe me, I went around, and around with this with Roland. AMB/Mylaps has the track infrastructure on lock. Their loops are installed in the track so getting another system in place is unlikely. I don’t know the details of the licensing and patents on the Loop itself, but any alternative would have to use it or be universally established enough to convince track operators to cut another trench in their very expensive asphalt. Also it would require convincing Roland or Jay to scrap some absurdly expensive hardware they only recently re-invested in. Because you think the transponder is expensive, you should see the price of the Decoder or a copy of orbits. Or those fancy multi charger travel cases the transponders are kept in. AMB gets everyones money.

Presumably the X2 exists to re-up the patents as much as establish a more robust DRM. Also I’m sure at some point in the near future they’ll just stop “supporting” the TranXs with a software update once they start seeing enough long dormant TranXs suddenly out turning laps again.

Lemons doesn't actually own the transponders that they rent out, they rent them from another organization. When they went to the new X2 transponders I asked Roland what would happen to the old ones assuming that Lemons owned them and maybe they'd sell them. Nope, they just went back to the company they rented from.

Would be cool if a clone was possible.

I knew the yellows were not Lemons. But I think Rolands Timing rig is all his.

I sent you a forum email. Not sure if it goes to a dead account of yours or if there is a problem with the msg forwarding from the forum. Someone else tried to pm me apparently and I never got it. I even checked spam folders etc etc.

Anyway, I need your mailing address.

i keep bird dogging facebook marketplace and craigslist for an old style wired non subscription one. Every once in awhile i see one come up for $100-$200 but they usually sell instantly.