Stereomicroscope Ringlight Supply

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As mentioned on my MBS-10 post the power supply of the ringlight I have for the former isn’t quite up the the safety standards I’d like. It was one of the cheaptest I could get and the quality of the power supply matches that. So I decided to built myself a new one! It’s an unregulated 12-15V power supply with an adjustable current limiter consisting of a TIP41C transistor. I used a lot of hot glue to secure the front panel components, as they wouldn’t probably hold on the plastic panel.

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SUN Netra X1 Capacitor Replacement

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For the keen observer, the picture on my last post about the SUN Netra X1 showed a couple suspicious capacitors around the processor. Two of them already started venting, so I figured to replace them before the short out and damage the mainboard. I also examined all other capacitors, including in the power supply and those all still looked fine. The broken capacitors in question are SANYO 1500uF/6.3V I replaced them with Würth 1500uF/10V capacitors (WCAP-ATUL 860040275011) which happen to have the same via spacing and diameter.

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Upgrading a SUN Netra X1 with a SATA SSD

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My old SUN Netra-X1 with an UltraSPARC-IIe+ lately had some bad sectors in it’s IDE hard drive, an old Seagate Baracuda 40GB. I found some IDE to SATA protocol converters online and figured might as well give it a try. Would be nice being able to put SATA hard drives or even SSDs into my old SUN machines. Bingo! wd1 at pciide0 channel 1 drive 0: <INTEL SSDSC2CW120A3> wd1: 16-sector PIO, LBA48, 114473MB, 234441648 sectors wd1(pciide0:1:0): using PIO mode 4, Ultra-DMA mode 2 I decided to do a reinstall of the system while I’m on it and booted bsd.

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NiCd Charger for Mining Lamps

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So I recently found this while clearing out the workshop of someone: It is a charging indicator for mining lamp charger racks, in partcular for Oldham-Arras lamps. It still had the bus bar mounting clips attached to it. So of course with this sitting around, I decided to built my own mining light charger. NiCd mining lights were charged using constant voltage, since they were used all ~20h with the charging requiring around 14-16h, so the time of the cells being charged and venting was kept fairly low.

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WiFi MQTT Controlled 4x High Power Relay

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Circuit Nothing much to say, it’s fairly standard. The relays are switched using BC517 darlington transistors. The unit is powered using a 230V to 12V AC/DC SMPS, the 5V for the ESP8266 board is derived from a standard LM7805. I used a WEMOS D1 I desoldered from another project, unfortunately a couple of the output pins didn’t work (probably damaged an internal trace while desoldering). So I used some wires to connect the signals to the pins that are working.

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Frequency Standard System: TCXO 10Mhz Mk1

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This is part of my Frequency Standard System. Oscillator VEB Narva 10Mhz The 10MHz TCXO itself is from east Germany made by NARVA. According to the data sheet it has a tolerance of ±2e-6, an aging of ±1e-6 and a thermal precision of ±3e-6. Given the timestamp of 1983 on it, it will have a deviation of approximately 3.7e-5 at this point. The TCXO power circuit consists of a 555 timer with an ON-delay of a couple of seconds to ensure the supply has stabilized.

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Frequency Standard System: Overview

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So with the built of my watch amplifier recently I got to question myself on how do I get a stable clock reference signal?. So I decided to build a frequency standard system. Unfortunately I don’t have a Rubidium reference right now but I decided to build everything in modules, so I can swap any part of it with a better or improved variant once I obtain the parts to build them.

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Personal library organization with Koha

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I looked at several other open source library software suits with an OPAC but they were either too much of an overkill or unmaintained for a while. My main requirement was the software to support MARC. I eventually decided to go with the traditional open-source ILS Koha. Installation I decided to install Koha in a LXC container with Debian running on my virtualization server which on itself runs Alpine Linux. So first I created a container:

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