If you're shopping for data acquisition recorders, the decision often comes down to more than specs. You might be looking at a used lab instrument that costs far less than a new unit but carries real uncertainty. The DATAQ DI-720-USB system is exactly that kind of opportunity: a complete setup at a price that makes you stop and think, with the obvious catch that it's used and untested. But used equipment asks you to do your homework.
Quick verdict
At $349.99, this used DATAQ system includes a DI-720-USB recorder, DI-5B signal-conditioning amplifiers, and a MESA interface. That's a lot of hardware for the price if everything works. The catch: it's sold as-is, hasn't been tested by the seller, and came out of a university surplus setting where it may have been sitting around dusty. Treat it as a project unit, not a plug-and-play solution.
Who it suits
This makes sense for a lab, tech, or advanced hobbyist who already knows their way around data acquisition gear. If you're comfortable opening a device, cleaning it, checking connections, and doing your own troubleshooting, the asking price gives you room to invest some effort. It's also a reasonable pick if you need the specific components bundled here and you're willing to buy the whole system to get them.
What stands out from the listed details
The big draw is the bundle. Rather than a bare recorder, this system arrives with extra hardware for conditioning inputs and connecting to a computer over USB, so you don't have to piece those parts together yourself. That can save you time and money compared with assembling a setup from separate purchases. Another useful detail: the unit is identified as a DATAQ Instruments product, and its country of origin is the United States. If you're familiar with DATAQ's ecosystem, you likely know what you're getting into. The used condition is clearly stated, so there are no surprises about it being new-just be aware that "used" here means surplus, dusty, and untested.
Meaningful trade-offs
The biggest downside is risk. The seller explicitly says they don't have the equipment to test the item and it's being sold as-is. When you buy a data acquisition recorder in that state, you're taking on the possibility that a channel might be dead, the USB connection may not be recognized, or internal components could need replacement. Dust may cause intermittent issues, so a thorough cleaning could be the first step.
There's also the matter of time. If you need a reliable recorder for a class, a research deadline, or a client job, an untested surplus unit probably shouldn't be your only plan. You need to be prepared to diagnose problems and potentially source parts, which can eat into any savings.
Bottom line
The DATAQ DI-720-USB system at $349.99 is a compelling find for the right buyer. If you're a seasoned user who wants a complete data acquisition package at the listed price and doesn't mind an as-is, untested condition, it may be the right call. If you need something you can power on and trust immediately, hold out for a unit that's been verified.
DATAQ DI-720-USB with DI-5B Amplifiers & MESA Interface
The bundle pairs the DI-720-USB main recorder with DI-5B amplifiers and a MESA interface. The reason to be interested is the completeness of the setup-you're not just getting a recorder, but also the signal conditioning and interface pieces that typically cost extra. The reality check is the condition: this is a used surplus unit sold as-is, without testing, and it may need cleaning before it's ready for work.
