xe1cdf

Radiocomunicadores del DF desde 1998

[Equationsinmotion @EqsInMotion]

These Fibonacci Gears Are Pure Math Magic! ⚙️

[UR4NWW Club Station @hamradiovin]

⚠️ Через надзвичайну ситуацію в Індонезії, з 11 по 24.09 2026 року просимо утримуватися від роботи на частотах

7,110 МГц — Голосовий аварійний зв’язок
7,100 МГц — Дані (режим JS8Call, USB)
145,880 МГц — uplink на LAPAN-A2/IO-86
435,880 МГц — downlink із LAPAN-A2/IO-86

de YB1BTM

[たいすーらせん @Yugemaku]

螺旋歯車とフェースギヤ

[ARISS - Amateur Radio on the ISS @ARISS_Intl]

Want to talk to the crew on the ISS using amateur radio?

Patience is key. When crew members have free time and choose to get on the air, they will use the ARISS cross-band voice repeater for casual contacts. These sessions are unscheduled, so the best approach is to listen and be ready.

After all, ham radio is just one of many ways the crew spends their off-duty time aboard the Station.

[Raspberry Pi @Raspberry_Pi]

Introducing the Raspberry Pi AI HAT+ 2, priced at $130. This add-on board for Raspberry Pi 5, powered by the Hailo-10H AI accelerator and 8GB of on-board RAM, is built to run LLMs and VLMs locally, without cloud or network dependencies.

The Raspberry Pi AI HAT+ 2 delivers 40 TOPS of generative AI performance and integrates directly with Raspberry Pi OS, including native support in rpicam-apps.

https://t.co/b91pCnE2e0

[UR4NWW Club Station @hamradiovin]

Сьогодні четвер, отже не забудьте приєднатися до APRSTHURSDAY net (00:00 - 23:59 UTC) що проводиться в мережі APRS 🌐 144.8 МГц

Підєднатися:
Destination Station = ANSRVR

Що писати: Message body = CQ [space] HOTG [space] your text check-in message of choice

[DX World.net @DX_World]

A feature on our hobby.

[Two Communications @2Communications]

UW4E Radio Club Station 📡 🇺🇦

[Jorge De Castro | EA1FWI @ThePCBDesigner]

This combination is amazing!

[Paul @paul_vk6]

Just purchased the icom ic-7610. Should be here in a few days. Looking forward to playing with it. I have a large new HF antenna getting built for me. Will pick it up next week. Fun times.

[DX World.net @DX_World]

"It's an amp, Jim - but not as we know it!" :-D

[ElectronicsNotes by Ian Poole @ElecNotes]

Understanding Antenna Polarisation

Radio antennas are sensitive to the polarisation of electromagnetic wave and this is an important aspect of their operation.

Antenna polarisation is an important factor when designing and erecting radio antennas or even incorporating them into small wireless or mobile communications systems.

Some antennas are vertically polarised, others horizontal, and yet other antenna types have different forms of polarisation.

For the electromagnetic wave the polarization is effectively the plane in which the electric wave vibrates.

This is important when looking at antennas because they are sensitive to polarisation, and generally only receive or transmit a signal with a particular polarization.

For most antennas it is very easy to determine the polarization. It is simply in the same plane as the elements of the antenna.

So a vertical antenna (i.e. one with vertical elements) will receive vertically polarised signals best and similarly a horizontal antenna will receive horizontally polarised signals.

It is important to match the polarization of the RF antenna to that of the incoming signal. In this way the maximum signal is obtained.

If the RF antenna polarization does not match that of the signal there is a corresponding decrease in the level of the signal. It is reduced by a factor of cosine of the angle between the polarisation of the RF antenna and the signal.

Accordingly the polarisation of the antennas located in free space is very important, and obviously they should be in exactly the same plane to provide the optimum signal. If they were at right angles to one another (i.e. cross-polarised) then in theory no signal would be received.

For terrestrial radio communications applications it is found that once a signal has been transmitted then its polarisation will remain broadly the same.

However reflections from objects in the path can change the polarisation. As the received signal is the sum of the direct signal plus a number of reflected signals the overall polarisation of the signal can change slightly although it remains broadly the same.

[Manu Merino @ec7zt]

Sota 2 Sota con EB2GKK/P Iñaki, desde EA1/BU-040

[Two Communications @2Communications]

Lampertheim, DL0WW Amateur Radio Club (LARC).

[SEARG Radio ( EI2WRC ) @seargnews]

#CQ #Contest
Today was an absolute feast on the #WARC and the rest of the bands.
#Hamradio #Amateurradio #DX #Xiegu #QRP #SWL 📶

[wa1gov @wa1gov]

CQ CQ on 7.043 MHz QRP-CW. #hamradio

[Mundo en Conflicto 🌎 @MundoEConflicto]

🔴 #AHORA | El NOAA detectó 5 llamaradas solares que golpearan la Tierra mañana. Se trata de la peor tormenta solar en casi 20 años. La alerta G4 implica que podrían producirse alteraciones en:

■ Comunicaciones
■ Apagones
■ Navegación
■ Operaciones de radio
■ Satélites

[David Marugán @RadioHacking]

A lo mejor tienes en casa un radio de Onda Corta, y piensas que es algo viejuno o antiguo. Te propongo este hilo para que descubras que no es así, y las cosas que se pueden hacer en esa banda. Muchas comunicaciones críticas residen todavía en ella. ¿Me acompañas? #Shortwave #SWL #Hamradio 📻📡

[RossRadio @cqcqcqdx]

Nostradamus trans horizon radar system. 288 conical antennae, over three 1/4 mi long branches. Detects aircraft flying 600-1500 mi away. System uses low frequency waves (6-30 MHz), which bounce off the ionosphere and allow the radar to detect targets beyond the horizon.