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Comment by teruakohatu | Hacker News Reader

That was a god read, thank you.

Do you have any insight into the economics of this in general compared to other disposable solutions. Are manufacturing old school magnetic stripe tickets, or just optical scanning/barcodes a lot cheaper?

I imagine magnetic stripes have a higher failure to read rate at the turnstile causing issues, while both them and optical scanning requires the ticket to be inserted into the machine, adding complexity and moving parts.

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I couldn't find a nice price breakdown. I'd expect the magnetic stripe tickets to be cheaper to manufacture, but since the NFC tickets cost pennies, there isn't a lot of money to save. I agree with you that magnetic stripes would have a much higher maintenance cost due to the mechanical aspect and the read/write head. Optical scanning seems less likely to work the first time, based on my experience with airplane checkins. NFC is probably the best from an ecosystem perspective since it can work with credit cards and phones as well. NFC readers are probably the cheapest since they are produced in large volumes for credit card point of sale.

I’ve occasionally gotten to watch transit workers open up and service the magnetic stripe card readers in the BART. Those things are complicated. It may well cost less to outright replace a contactless reader module on a fare gate than to service a magnetic stripe ticket machine once. Even an Adafruit PN532 board is only $40.

And if a machine jams not only do you need staff to spend hours to repair it, but you need to pay staff, or contractors, to do it.

I've not worked with the Adafruit PN532, but for an extra $10 you can get a Pepper C1 USB from Eccel which is very easy to work with. It is a stand-alone device, so you don't have to connect it to anything but power. Has WiFi & BT built in and has a built-in web server to configure it with, you can have it make calls via REST, MQTT, WebSocket.

Interestingly, the Pepper C1 is essentially a PN518 (presumably a sibling of the PN532 on Adafruit's board) hooked up to an ESP32. So a very simple device - and I've had a project on the backburner which is pretty much a DIY clone of it. If they made a USB-C version I'd ditch mine and buy it in a heartbeat.

BART stopped accepting paper tickets last year, presumably because of the complexity (not just the ticket barriers, but also the fare machines and add value machines that also had to handle them): https://www.bart.gov/news/articles/2023/news20230911

Yeah, they moved to a native integration with Apple/Google/Samsung Wallets, and Clipper cards as a backup (but they really try to discourage them, at least for tourists).

The cool thing is that their thing doesn't work with all Android phones for an unknown reason (various people from the transit agency said "oh Android? Yeah it doesn't always work with Android"), which you have no way of knowing before topping up money and trying to use your phone.

If anyone is curious, it was a Xiaomi Redmi phone, a midrange one that has no issues paying over NFC. A OnePlus next to it with the same Android version worked just fine.

FWIW, Montreal used to have mag strip paper tickets and turnstiles to match, but ever since the new paper tickets rolled out we have new svelte turnstiles with an NFC reader exclusively.

They've been trying to get contactless bank card payments going on the same turnstiles but roll-out has been bogged down by other transit agencies apparently.

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