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Nuburu Inc of Centennial, CO, USA — which was founded in 2015 and developed and previously manufactured high-power industrial blue lasers — has announced a quarterly update on its business performance, strategic initiatives, and outlook for the upcoming period...

КПІ ім. Ігоря Сікорського та ФРУ Дефенс готуватимуть менеджерів для оборонно-промислового комплексу України kpi вт, 09/30/2025 - 22:09

I was inspired by the recent post from u/MaxwellHoot regarding a local parts inventory system. I did indeed end up using one of my old Palm devices, the SPT1800 to be exact. It has a built in laser/barcode scanner just for this purpose. While it can't do QR codes, the barcodes work just fine. Using abandonware - the "CatScan" Palm app, "J-Pilot" Linux app, and a custom script to turn the database into an HTML file, I now can scan all my mouser bags and inventory items rather quickly. The webserver is read-only, but still useful. It might be fun to develop everything into a kiosk, but I don't have time right now. submitted by /u/vtfrotex [link] [comments]

Today, the FPGA company revealed an array of new announcements at its annual Altera Innovators Day developer conference.

One of my electronics interests is building radios, particularly those featured in older UK electronics magazines such as Practical Wireless, Everyday Electronics, Radio Constructor, and The Maplin Magazine. Most of those radios are designed to run on a 9-V disposable PP3 battery.

Wow the engineering world with your unique design: Design Ideas Submission Guide

Using 9 V instead of the 3 V found in many domestic radios allows the transistors in these often-simple circuits to operate with a higher gain. PP3 batteries are, at a minimum, expensive in circuits consuming tens of mA and are—I suspect—hard to recycle. A more environmentally friendly solution was needed.

In the past, I’ve used single 3.6-V lithium-ion (Li-ion) cells from discarded e-cigarettes [1] with cheap combined charger and DC-DC converter modules found on eBay. They provide a nice, neat solution when housed in a small plastic box, but unfortunately generate a lot of electromagnetic interference (EMI), which falls within the shortwave band of frequencies (3 to 30 MHz) where a lot of the radios I build operate. I needed another solution that was EMI-free and environmentally friendly.

Solution

One solution is to eliminate the DC-DC converter and string together three or more Li-ion cells in a battery pack (B1) with a variable linear regulator (IC1) to generate the required 9 V (V1) as shown in Figure 1. Li-ion cells, like all electronic components, have tolerances. The two most important parameters are cell capacity and open circuit voltage. Differences in these parameters between cells in series lead to uneven charging and ultimately stressing of some cells, leading to their eventual degradation [2]. To even out these differences, Li-ion battery packs often contain a battery management system (BMS) to ensure that cells charge evenly.

Figure 1 Li-ion battery pack, with 3 or more Li-ion cells, and a variable linear regulator to generate the required 9 V.

As luck would have it, on the local buy-nothing group in Ottawa, Canada, where I live, someone was giving away a Mastercraft 18-V Li-ion battery with charger as shown in Figure 2. The person offering it had misplaced the drill, so there was little expense for me. Upon opening the battery pack, it was indeed found to contain a battery management system (BMS). This seemed like an ideal solution.

Figure 2 The Mastercraft 18-V Li-ion battery and charger obtained locally.

Circuit

The next step was to make a linear voltage regulator to drop 18 V to 9 V. This, in itself, is not particularly environmentally friendly, as it is only 50% efficient, and any dropped battery voltage will be dissipating as heat. However, assuming renewable power generation is used as the source, this would prove a more environmentally friendly solution compared to using disposable batteries.

In one of my boxes of old projects, I found a constant current nickel-cadmium (NiCad) battery charger. It was based around an LM317 linear voltage regulator in a nice black plastic enclosure sold by Maplin Electronics as a “power supply” box. The NiCad battery hadn’t been used for over 20 years, so this project would be a repurpose. A schematic of the rewired power supply is shown in Figure 3.

Figure 3 The power supply schematic with four selectable output voltages—6, 9, 12, and 13.8 V.

In Figure 3, switch S1 functions as both the power switch and selects the output voltage. Four different output voltages are selectable based on current needs: 6 V, 9 V, 12 V, and 13.8 V can be chosen by adjusting the ratio of R2 and R3-R6 as shown in the LM317 datasheet [3]. R2 is usually 220 Ω and develops 1.23 V across it, the remaining output voltage is developed across R3-R6. To get the exact values, parallel combinations are used as shown in Table 1.

Resistor #	Resistors (Ω)	Combined Value (Ω)
3	910, 18k, 15k	819
4	1.5k, 22k, 33k	1.35k
5	2.2k, 15k	1.92k
6	2.2k	2.2k

Table 1 Different values of paralleled R3 to R6 resistors and their combined value.

A photograph of the finished power supply with a Li-ion battery attached is shown in Figure 4.

Figure 4 A photograph of the finished power supply with four selectable output voltages that can be adjusted via a knob.

Results

Crimp-type spade connectors were fitted to the two input wires, which mated well with the terminals of the Li-ion battery. Maybe at some point, I will 3D-print a full connector for the battery. With the resistor values shown in Figure 3, the actual output voltages produced are: 5.96 V, 9.03 V, 12.15 V and 13.8 V. While these are not the actual designed values due to the use of preferred resistor values, it is of little consequence as the output voltage of disposable batteries varies over their operating time and there is of course a voltage drop due to cables. With this power supply, though, the output voltage of the power supply will remain constant during this time, even as the output voltage of the Li-ion drops due to its discharging.

Portable power

Although the power supply was intended for powering radio projects, it has other uses where portable power is needed and a DC-DC converter is too noisy, like sensitive instrumentation or some audiophile preamplifier [4]. 

Gavin Watkins is the founder of GapRF, a producer of online EDA tools focusing on the RF supply chain. When not doing that, he is happiest noodling around in his lab, working on audio electronics and RF projects, and restoring vintage equipment.

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References

1. Reusing e-cigarette batteries in a e-bike, https://globalnews.ca/news/10883760/powering-e-bike-disposable-vapes/
2. BU-808: How to Prolong Lithium-based Batteries, https://batteryuniversity.com/article/bu-808-how-to-prolong-lithium-based-batteries
3. LM317 regulator datasheet, https://www.ti.com/lit/ds/symlink/lm317.pdf
4. Battery powered hifi preamp, https://10audio.com/dodd_battery_pre/

The post An off-line power supply appeared first on EDN.

Welcome to the first All About Circuits Summit Day of 2025! This guide will introduce the features of our first Wednesday schedule and help you plan your month-long participation.

Anritsu Corporation will participate in the upcoming India Mobile Congress (IMC) 2025, taking place in New Delhi, India, from October 8 to October 11, to showcase its latest innovations in communications test and measurement solutions.

As the mobile and connectivity industry continues to expand with the rapid adoption of 5G, IoT, and emerging technologies such as AI-driven services, cloud computing, and immersive XR applications, the demand for robust, reliable, and efficient test solutions has never been greater. At IMC 2025, Anritsu will highlight its comprehensive portfolio designed to meet these evolving needs, supporting operators, device manufacturers, and ecosystem partners in accelerating their technology development and deployments.

Virtual Signalling Tester

5G Network Simulator, a software-based solution for 5G IoT chipset and device testing. It enables virtual 5G network simulation on a PC, supporting RedCap tests and efficient device verification.

Radio Communication Test Station MT8000A

All-in-One Support for RF Measurements, Protocol Tests and Applications Tests in FR1 (to 7.125 GHz) and FR2 (Millimeter-Wave) Bands. MT8000A is used by Mobile Chipset, Mobile Handset, IoT Device, 5G base Station R&D and manufacturing companies.

Field Master Pro MS2090A

Handheld Spectrum Analyzer delivers the highest continuous frequency coverage up to 54 GHz and real-time spectrum analysis bandwidth up to 150 MHz to address current and emerging applications such as 5G &LTE Base Station Measurement, Satellite System Monitoring, Interference Hunting, EMF measurement and much more.

Anritsu Collaborates with Altair to Demonstrate Integration of Anritsu Monitoring Systems with Spectrum Management Software WRAP.

Altair WRAP integrates georeferenced data from Anritsu spectrum analyzers to validate coverage, interference, and spectrum compliance with field reality.

VectorStar Broadband VNA ME7838

The VectorStar ME7838 Series broadband VNA offers the widest available 2-port single frequency sweep from 70 kHz to 110, 125, 145, and 220 GHz with mmWave bands up to 1.1 THz. Vector Star is a cost-effective solution for OnWafer Measurements, RIS, Novel Channel Sounding applications along with active and passive devices measurement supporting 5G and 6G technology.

Optical Spectrum Analyzer MS9740B

MS9740B offers Single mode and Multimode Fiber application and high-speed optical devices such as optical transceivers, VCSEL, and DFB light sources testing R&D and production.

The post Anritsu Showcases 6G and NTN Test Solutions at IMC 2025 appeared first on ELE Times.