R&S EB200 Miniport Receiver Dial Knob
I was lucky enough to get a Rohde & Schwarz EB200 Miniport receiver in working but less than mint condition. Apart from cleaning and fixing some bumps on the covers, the dial knob was very broken. This knob is a custom part designed by R&S that proved impossible to get in 2023. Repairing the original […]
Elecraft K3 “ERR 12V” Fix
The Elecraft K3 is a very well known HF transceiver with a great reputation and it follows quite a different philosophy from what (mainly japanese) competitors were offering at its time. This particular unit, from my good friend Angel EA4XT started giving “ERR 12V” and the output power dropped to a few watts each time. […]
Icom IC-7200 Cammo Paint
I once saw pictures of a beautiful IC-7200 with a few variants of cammo paintwork. It always remained in my mind to one day get one, but I never saw it available. So I bought a used 7200 (I should have chosen one that was not mint, like this one was…). I completely disassembled it, […]
Icom IC-RP1510 “R3” Repeater
I was asked to repair/refurbish the “R3” (now RV54 with the new legislation) repeater from URE Guadarrama, usually running in a privileged location in the Alto del León (1.150 m), around 50Km north-west to the center of Madrid. The repeater had developed severe loss of sensitivity and also TX range. Both the repeater and the […]
Icom IC7300 RTC Fix
My friend Nacho EA4GZR kept complaining about his Icom IC-7300 not keeping time as it should, gaining “a lot” more than expected as compared to the companion IC-9700 that he has sitting next to it. The IC-9700 has a NTP client, so it was easy to him to see how much the clock was gaining […]
IC7100 Vertical Base
The IC-7100 is a very nice rig but I quite do not like the “console” format, I prefer the classic style of most other rigs. After a few tries, I am finally happy with this 3d-printed stand. (Click on the pictures for hi-res) It is very easy and natural to use the rig in this […]
IC-R8500 Low Sensitivity
I was happy with the IC-R8500 until one day I used a splitter to connect another receiver along this one to the same antenna at the same time, and I found it was performing a worse than the other. Moderate signals were readable on both but I could hear clear voices on the other than […]
IC7100 Dual-head Switch
I needed to operate a single transceiver from two different locations, using two controllers. Having to disconnect the cables was not an option and a simple “Y” would (most probably) damage something. I thought I could build an automatic switch that could change the connection from one controller to the other automatically. With the schematics, […]
Kenwood TM451 TCXO Upgrade
Being used in a mountain-top repeater, our TM451 transceivers suffered severe frequency shifts as the temperature varied. They are exposed to temperatures as low as -15C in winter and as high as 45C in summer, and the original crystal oscillator is too sensitive to this variations. We measured the repeater to be as high as […]
10Mhz GPSDO I (spanish)
Utilizando un receptor GPS con salida de 10KHZ es sencillo crear un PLL que nos permita “disciplinar” un oscilador de 10Mhz. Esta es una manera fácil y barata de disfrutar en casa de una señal patrón de gran precisión, impensable antes de la era GPS. La constante de tiempo del PLL nos permite jugar con […]