Category: Electronics

Error opening serial port

Encouraged by the latest developments, today I started building a new application that will  allow remote connection to Kenwood TH-D74, remote control and APRS data transfer. However, while building and running the app I got the following error: If you encounter this, be aware that it is generated by application sandboxing. You can think of using …

Beacon with SiLabs module

This is a beacon project started by my friend YO5VAE. He faced some issues while programming of the Si4463-based module and I thought I might give a hand. I resoldered the entire project on an empty Arduino shield to allow expansion of the project with some additional modules. Below are some pics, but probably the …

Repair of a cassette deck

I twenty dollars for this superb cassette deck. The playback and recording heads were in excellent shape and I used this deck for some years, playing and recording on NOS (new old stock) tapes, mostly chrome type II and metal – type IV, that I purchased on eBay. However, one day the entire head block …

A cold war era reel-to-reel

This old reel-to-reel was the joy of my teenager days, Back in eighties I was listening to VOA and Radio Kuweit and I was recording mostly on east-german OR-WO tapes (that were quite decent) because the BASF and Agfa were in shortage. Western music reached the black market usually by pilots that were operating civil …

Ferrite beads

I ordered some ferrite beads for a RF circulator project I currently work on but these might also be very handy for the SWR bridge project. These are extremely efficient for RF supression, or at least this is what they say.

Boards for prototypes

For low frequency projects, a fast way to prototype is using a bare PCB and scratch some dividers that allow “manhattan” style prototyping. I am especially very fond of this prototyping technique and I believe that PCB design should be avoided in the early stages of prototyping. Jim Williams was an artist in such designs. …

A quickie on USB Endpoints

Endpoints are essentially the USB addresses that USB data is sent to or from. Now, here is the trick. The transfer direction naming convention is a bit unintuitive. Contrary to — at least — what I imagined, an IN Endpoint will transfer USB data from the USB device to the host PC, while an OUT Endpoint …

SCPI on Mac

Some more days passed and some more finishing touches added to my MacSCPI app. It is entirely dependent on hooking the device via the USBTMC driver, but it works fine and is stable: I had some problems with buffer padding and the output it is still not 100% gibberish–free , but I assume I have to play with …

USBTMC driver for Mac

After some head banging, I finally managed to send SCPI commands from my Mac to my Agilent (Keysight) DSOX2002A. I’ve worked on this since december last year. Almost a year, but I did not spent a sustained amount of effort. I did it just during my free time. I still have a day job that …

Writing serial drivers for OS X (1)

At least one thing can be improved on Mac Dev Center: the code sample repository. I am not talking about documentation. In this particular case, there’s not much new to write about. The I/O Kit documentation (grab the pdf while it is stil there) is sufficient. On the shelves are tons on books about C and …