Personal library organization with Koha

Banner
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:

Read More

Sub-distribution panel for my datacenter

Banner
Similarly to my workshop I decided to built a dedicated distribution panel for my data center installation. Once I redo the electrical installation in the house in the coming year, this panel may end up being partially redundant (i.e. surge protectors and RCD) but I guess redundancy is better anyhow, rather have two breakers trip at the same time than one failing to do so. 1, 2) Main RCD 25A 30mA A Type 3) Main circuit breaker 16A B type, 4,5) Branch breaker 10A B type, 6,7,8) Branch breaker 6A B type, 9) Single phase meter, 11,12) Surge protectors

Read More

Gossen Pantam Konstanter T2 33 015 Repair #2

Banner
Continuing from the previous I’m going to document repairing the second Gossen Pantam T2 33 015 with this entry. Shorted ASY14 transistor This one had an odd behavior, where it wouldn’t built up voltage and when cutting power to it there would suddenly be a voltage spike on the output. I first suspected a broken capacitor (as with the other most electrolytic capacitors didn’t look too good). So I checked for shorts on the capacitors, and immediately found one but not on a capacitor but between the base and emitter of one of the large ASZ15 transistors.

Read More

Gossen Pantam Konstanter T2 33 015 Repair #1

Banner
I recently got two Gossen Pantam Konstanter 33 015 lab supplies from the mid to late 60s as shown above. Both of them are their own can of worms and need some fixing. The following describes how I fixed one of them , I’ll do another post once I fix the second one. This one is peculiar in that someone already had a go with it and “fixed” some of the things, multiple parts have been replaced at some point and there are clear signs of amateur soldering, in that wires have been touched and scorched by a soldering iron.

Read More

Measuring mechanical vibrations of watches using a Piezo element (Part 1)

Banner
So the other day I wondered whether it is possible to measure mechanical vibrations of wristwatches using a Piezo element (piezoelectricity). I did a little bit of research and found several people who already built something like this. I decided to go with Stefan Vorkoetter’s excellent design (also checkout their software watch-o-scope). Coincidentally I had the same or at least a very similar case as the one shown on their instructions, so I figured I use it for mine as well.

Read More

┬▒5V 300mA Bipolar Desk Supply

Banner
Schematic I decided to go with a fairly standard 7805/7905 supply with protection diodes, nothing really worth mentioning here. [yes, I know four point cross connections on schematics are not in accordance to DIN schematic standards] Construction Nothing really worth mentioning with the construction either, other than that the electrolyte capacitors were wobbly so I hot glued them to the board to ensure they don’t eventually break off with oscillations from the transformer.

Read More