29 August 2020

Neon Tester TS-990

My neon/nixie/gas-filled-tube tester homemade 5 years ago still works, but it is cumbersome to carry the device and a 12V battery when you need in on the field (A.K.A. flea markets...).

Instead of looking for a different case and fit a LiPo+booster, I decided to buy the TS-990 Neon Tester, that has a comfortable case and works off 4xAA batteries. Hard to beat at 10€/12US$!

Size is about the same :)


I did not expect it to pulse on/off the HVAC every second, but that helps to see the gas in daylight. Also it is more powerful than the CCFL inverter, as it lights up the gas even without touching the tube glass.



28 August 2020

Jam Replay Bluetooth speaker battery replacement

While I've been blog-silent this August 2020, I do have thought of electronics and done some repairs here and there. Like a relative's 10 years old laptop that does not support the latest Win10 updates and needed a clean-up of the CPU fan, or a desk lamp that melted the lamp holder. Usual business I'd say.

Back home, we wanted to use my daughter's Jam Replay Bluetooth Speaker HX-P250 that would not power up. Recharging didn't help since the red LED would not light up. Highly suspect: the battery.

Old (blue) and new (silver) battery.
This speaker is surrounded by an integral rubber cover that can be removed with little patience. Then, four screws on the bottom, two on the side, carefully take apart the three parts (they are connected with THIN wires that can be easily damaged, so be extremely gentle!).

The battery measured 0.587V even after trying a recharge. Way too low. As someone already documented for a similar Jam Replay speaker, cut the old battery away keeping its wires and fit a replacement.

I had a spare 3.7V 400mAh, which has less capacity than the original (meaning shorter play time), but allowed me to close the case in less than 30 minutes and reclaim the lab desk for other projects. You may buy similar batteries online, just pay attention to the dimension, the voltage 3.7V and the technology Lithium-based.

Recharging test.
Before fitting the rubber back in place I tried a recharge and a pairing session. Both were positive, so now the speaker awaits the next opportunity to be heard.

Personal note. Keep the thing's battery charged up. The circuit might be drawing some little current and without overdischarge protection the battery will be discharged below the point (voltage) of no-return (about 2V for Lithium-x batteries). We hadn't used the speaker for months.