Mode HamDRM

HamDRM: digital SSTV pictures (EasyPal, QSSTV DRM).

Group	Amateur: digital
Default frequency	14.233 MHz
Default sample rate	2 Msps
In the mode list	Digital SSTV, 14.233 MHz

Step-by-step: Tutorial-HamDRM

What HamDRM is

HamDRM (EasyPal, QSSTV DRM) sends pictures as files over a DRM-style OFDM signal in a normal SSB bandwidth.

Frequencies and settings

Digital radio on long, medium and short wave.

Setting	Value
Start frequency	14.233 MHz
Tuning range of the mode table	1 to 30 MHz
Sample rate asked	2 Msps
Lowest working rate	250 ksps
Channel width	3 kHz

OnAir takes any frequency you type; the numbers above are the mode's starting point and the range its table describes. In the app the shortcut label is Digital SSTV, 14.233 MHz.

What OnAir shows

Audio and station information; Journaline pages (packet mode data service).

Tips and caveats

• Checked with generated signals and impairments; recordings of real signals welcome.
• Which radio: An RTL-SDR can receive HF only in direct-sampling mode, which OnAir offers in its radio settings; results depend on the antenna. SDRplay and Airspy HF+ radios are better suited.
• Try it without a radio: most modes include a built-in synthetic test signal, so you can open the screen and try the controls first.
• Receiving and the law: Amateur radio signals are meant to be received. Receiving needs no licence in most countries; OnAir does not transmit. See Legal.

Related pages

• All modes, Amateur: digital
• Supported radios, Troubleshooting, FAQ
• More in Amateur: digital: FT8, FT4, FT2, WSPR, JT65, JT9, Q65, FST4, MSK144, PSK31, JS8Call, RTTY, CW, SSTV, Olivia, Contestia, MFSK, THOR, DominoEX, Hellschreiber