IK1ZYW Labs

I got a second-hand-new Baofeng UV-3R Plus and it shows a problem that has not been documented (or I use the wrong search keywords): the LC...

I was testing some Sega Master System 2 vintage game consoles with a friend and we couldn't get a signal out of them. I used a portable...

New look for the MK-208 This was an easy fix, on an easy to rework PCB. I replaced the five largest electrolytic capacitors in the MK-208 PA...

The (Excelltel) MK-208 PABX (and alike) is a modern local telephone analog exchange for small offices. "Modern" because it was ...

I am currently troubleshooting the CRT monitor of an Olivetti typewriter that produces composite video at 70 Hz refresh rate. Weird? Indeed....

Over the years I have repaired few devices and never found a RIFA capacitor. Until today when I finally met them in all their smelly glory. ...

I've received a homebuilt oscilloscope from 1950's. Scuola Radio Elettra, an Italan company back then, was very popular and helped m...

Now that my interests are expanding to retrocomputing, I feel the need to read those C64 tapes. Which means that, somewhere, a tape/cassette...

This Summer we spent 10 days driving around Greece in a rented car. Being high season I looked for cheaper alternatives to the big names. ...

I bought a Fairchild 7050 multimeter because it has slightly larger than usual Nixies. There was no indication of its state, but I could cou...

For the blinkenlights project two posts behind I chose to use an ATmega48 because the firmware is very small, while all my other (clock) pro...

ATTENZIONE. LE INDICAZIONI RIPORTATE DI SEGUITO SONO IL RESOCONTO DI UNA OSSERVAZIONE PERSONALE PER ILLUSTRARE UN POSSIBILE GUASTO, NON SONO...

Could I refrain from powering up the Tek VXIbus mainframe? I do have a rather equipped "lab" and this was the chance to use severa...

If you could publish just once a month, would you miss the opportunity to post on the unique day of a leap year? Here's my February 2024...

4k7 ohm 5%, right? Here's a post to mark January 2024. I've been doing very little in the lab because of work, flu and mostly cold t...

I have a cordless hair&beard "styling kit" from Braun, model 5514, that doesn't hold the charge anymore. I use my solderin...

As a self-assignment for troubleshooting the Hameg oscilloscope, I needed to measure kiloVolts. The world agrees that you need to arrange a...

R ight after fixing the high voltage being too high (-2500V vs -1900V) on the Hameg HM203-6 oscilloscope, the trace disappeared. Note that I...

I used the Hameg HM203-6 scope to test the Tennis-for-Two emulator I quickly built in November 2023. I also carried it to the exhibition ven...

The last PCB I designed includes an ATtiny85 microcontroller. Since it will not need many updates I did not include the ICSP header for repr...