Automated Station ID with ISD1820

The ISD1820 is a sound recorder and playback module capable of storing 20-second audio recordings. It features the ability to initiate playback with a button press or a pulse, which is very useful in automated transmissions. The playback signal can be generated manually by tapping the playback button onto a radio’s PTT button, or by using a dedicated controller (such as a timer or an Arduino) for sending transmissions at regular intervals. To send the module’s audio signal to a radio transmitter such as a VHF radio on FM mode or an HF radio on SSB, connect the speaker out to the microphone line input of the radio. This module can be used to send repeated transmissions such as station IDs or for calling a CQ.

ISD1820 is sound recorder and playback module

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Night Sky in Focus | Astronomy and Amateur Radio
© Anthony Urbano | Manila, Philippines


DIY Straight Key and Dual-Paddle with Iambic Keyer

I have built a Morse code straight key and iambic keyer for Morse code communications.

The straight key was made from brass bars, some bearings, and screw. It was then mounted on the same aluminum plate with my home-brewed electronic keyer with paddles and desk microphone.

Home-brewed straight key and dual-paddle with an iambic keyer

The keyer uses an Arduino Uno and a few components such as a potentiometer for adjusting the words per minute (WPM), a small speaker, some resistors, and LED indicators.

To view all posts about amateur radio, click here.

Night Sky in Focus | Astronomy and Amateur Radio
© Anthony Urbano | Manila, Philippines