gerard – Page 3 – Geronimo/370

Retro Z80 computer (4) – Dual Serial Module

Posted on2021-12-15

And another one bites the dust… The Dual Serial SIO/2 module has been assembled and soldered. With this one I had to search for the value of the resistors, because the info was not in the documentation. Eventually I ended up looking at the pictures of an assembled one online… Read the rest

Retro Z80 computer (3) – Memory module

Posted on2021-12-152021-12-15

And the memory module for my Z80 computer is finished. It contains 512K of ROM and 512K of RAM memory.… Read the rest

Retro Z80 computer (2) – backplane and CPU board

Posted on2021-12-152021-12-15

Yesterday evening I assembled and soldered the backplane board and the CPU board. Around 600 solder joints…… Read the rest

Retro Z80 computer (1) – plans

Posted on2021-12-112021-12-15

This holiday season I’m going retro, and build my own Z80 computer from a kit. The kit offers all the separate parts and one has to assemble the whole thing… All the parts Modular design The design of this computer is totally modular. Because it has been thought out very… Read the rest

Resonance measurements / filters

Posted on2021-12-052022-03-02

Yesterday I started with Capacitors / capacity and coils / inductance. Today I did some extensive measuring, first on a C and L in a series tuned circuit, then on a parallel tuned circuit. See schematics here below: For these measurements I used the same setup as yesterday. But this… Read the rest

Resonance frequencies

Posted on2021-12-042021-12-041 Comment

In the HAM course I am following to become a licensed radio amateur, the topic of resonance frequencies came along. To wrap my head around it I did some experimenting. You can find the result below. I have an assortment of capacitors and coils that I can use for these… Read the rest

HAM-gadget (6) – adjustment & enclosure

Posted on2021-11-132021-11-13

In this version I built in the possibility to adjust the summer and wintertime offset from UTC. It’s a very crude offset, I just add or subtract the offset from the UTC hour. Have to think of a better way to do this… Enclosure I built in the gadget in… Read the rest

HAM-gadget (5) – menu structure

Posted on2021-11-072021-11-08

This weekend I built in a menu structure into the HAM-gadget. Also I created a possibility to store and retrieve settings to the ATMEGA328P’s EEPROM, so they are saved for the next time you switch on the device. For now, you have to retrieve them manually, but that’s quicker then… Read the rest

HAM-gadget (4) – keyboard added

Posted on2021-11-052021-11-06

After a lot of fiddling, trial and errors, I finally got the matrix keyboard to work. Also, as the project has passed the prototype stage, I threw together everything on a PCB in preparation for mounting it in a casing. Note to self:next time first cut the PCB to size… Read the rest

HAM-gadget (3) – connected the GPS

Posted on2021-10-242021-10-24

Finally got it to work After much fiddling and trying out different libraries I finally had a bright moment and reverted back to the library that has been specifically made for this GPS module by Velleman… Duh… prototype, software version 0.5 That worked, also after some tweaking of the wires… Read the rest

HAM-gadget (2) – new Arduino board

Posted on2021-10-232021-10-23

Arduino board left and center, GPS module on the right, GPS antenna on top Today some new stuff arrived. First of all the new Arduino RP2040 Connect board, a Wifi capable board with a much smaller form factor then the Uno clone I had before. Second came in the GPS… Read the rest

HAM-gadget (1) – building a shack gadget

Posted on2021-10-222021-10-23

Today I worked on version 0.1 of my new project. It’s in the prototype stage as you can see in the picture below. For this test it’s an Arduino Uno (clone by Velleman), two DS18B20 temperature sensors and two 20 x 4 displays. This version is for setting up the… Read the rest

My audio stack

Posted on2021-10-092021-10-09

Below you can see my audio stack. At this moment it is in use for work related Teams and Skype meetings, later on, when I passed my exam and have obtained my license, I will also use it for HAM voice activities (QSO’s). The stack: Audio stack Components One by… Read the rest

Uptime > 1 year

Posted on2021-10-012021-10-012 Comments

My Linux server (Debian 10 ‘Buster’) is running over one year now:… Read the rest

Current workplace

Posted on2021-09-172021-09-17

This is how my current workplace looks.… Read the rest