Geronimo/370

Last connections made (QSO’s)

Posted on2022-05-262023-04-04

Below you can see the last 15 QSO’s I made, as logged on QRZ.com. A yellow star means the contact has been confirmed by the other station, a little grey circle means confirmation has been requested. Normally I ask for confirmation with each contact; absence of a yellow star or… Read the rest

HAM-gadget (7) – smaller enclosure

Posted on2023-11-022023-11-06

I decided to rebuild my HAM gadget. The enclosure I used, being a 19 inch rack enclosure, was way to big for the functionality it offers. So I took the guts out and purchased a more suitable housing. This exercise also needed a change in the software, because one screen… Read the rest

Another new clock

Posted on2023-07-16

Remember that Making a new clock (1) blog post? That one was to honour my dad’s old nixie clock. It’s in my office / HAM shack. Now we wanted another clock for another room. I decided to use the same parts and the same software, but built it a lot… Read the rest

Making a new clock (1)

Posted on2023-01-022023-01-202 Comments

As you could have read in my previous post, I decided to create my own digital clock to replace the old nixie clock (R.I.P). Components The components I will be using are: The casing of the old nixie clock An Arduino Uno (for programming the ATMEGA328p chip. Actually that chip… Read the rest

Fixing old Nixie Clock (3) ?

Posted on2023-01-021 Comment

Well, maybe you remember the previous posts about my dad’s nixie clock? I was very satisfied when I got it working again. Now, after 8 months it finally broke down completely. Oh well, it lasted for (I think) over forty years! New beginnings I decided to take the guts out… Read the rest

Retro Z80 computer (12) – C compiler

Posted on2022-12-082022-12-10

After having coded in ASM assembler and in Z80 assembler (see this post), now I also have found a C compiler. As far as I can tell, it adheres to K&R (Kernighan & Ritchie) rather well. I found it here. Like assembler, this was a trip down memory lane for… Read the rest

Retro Z80 computer (11) – (dis)Assembler

Posted on2022-12-061 Comment

At first, on my retro Z80 (RC2014) computer, I was using the assembler that came with CP/M, named ASM. Later on, looking for the Z80 block transfer instructions and not able to find them, I found out that it is an 8080 assembler. (hey, it’s been a long time since… Read the rest

Common mode filters

Posted on2022-05-212022-05-214 Comments

This afternoon, I will be taking my Novice exam. So in preparation of being allowed to transmit, I decided to create a barrier for HF. I did so by making a number of loops (7) in the coax cables, just above the ceiling. These loops act as coils and they… Read the rest

My bike

Posted on2022-05-092022-05-09

Recently, I traded in my BMW R1200 GS for another bike, the K1600 GTL. See pictures below. It is a very, very comfortable motorcycle. It has a lot of power as well, since it has a six cylinder engine with 1650 cc, about 160 Horse Power and a max torque… Read the rest

FT8 data from the noise

Posted on2022-04-302022-04-30

It’s truly amazing what can be accomplished with digital modes like FT8… Noise Have a look at this waterfall, it looks like the 10 meter band is dead, it only shows a few very faint signals in the 10 meter band: Despite the weak signals, the FT8 program I use,… Read the rest

Fixing old Nixie Clock (3)

Posted on2022-04-282022-04-28

Capacitor replaced The replacement of the power supply capacitor with a new one cleaned up the pulses nicely. The clock is running properly again for about two days now.… Read the rest

Fixing old Nixie Clock (2)

Posted on2022-04-232022-04-233 Comments

Remember that old Nixie Clock? For a while it ran properly, but now it skips time again at random intervals. So I got that big capacitor out that I suspected right away, because it has been in there for over 40 years. And unlike me, these things do not age… Read the rest

NanoVNA measuring antennas

Posted on2022-04-222022-04-23

Yesterday I received my NanoVNA (small Vector Network Analyzer). Among other things we can measure the return loss in antennas (or the Voltage Standing Wave Ratio or VSWR for short). Return loss or VSWR VSWR is the ratio between the energy that goes to into the transmission line TO the… Read the rest

Coax switches, measuring

Posted on2022-04-172022-04-17

An interesting video by W2AEW about measuring on coax switches to make sure one can leave a receiver connected when transmitting over another connection of the same switch:… Read the rest

SDR control iPad app for ICOM sets

Posted on2022-04-162022-04-16

Today I came across a very nice app with which one can control Icom transceivers. It is available in the App Store and it’s called SDR-Control for Icom. It works for LAN connected radio’s, so no cables needed, you can operate your set via Wifi. Icom’s IC-705, IC-7610 and IC-9700… Read the rest