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Getting started with PSK31

I saw a great presentation on PSK31 using the nue psk portable modem at the Mesilla Valley Radio Club this past weekend. The Nue PSK modem let's you get on the air with PSK31 without a computer. It uses an on-board micro-controller to handle the modem operations and includes an LCD for the waterfall display.

It occurred to me that my Windows Mobile enabled phone also has a programmable processor and a decent LCD display, so I went searching for PSK31 software for the Windows Mobile platform. NT7S quickly pointed me to Pocket Digi. It's a great little program that was easy to install and use! So far I've been able to decode psk31 just by placing my phone close to the speaker of an HF rig and selecting QSOs on the waterfall display.

On my Treo phone, I did have to do one quick little workaround. I first open the Windows Media Player and play any song. For some reason, this alerts the platform or the software that the speaker and microphone exist. If I don't do this, PocketDigi wakes up and complains that it can't access the microphone on the Treo.

Nobody heard me last night on transmit. On the chance that the issue is caused by my headphone speaker being used as the input to the PTT microphone, I went searching for audio-out to mic-in circuits and found this great page by G4NSJ with lots of interface circuits and info.

I'll add updates on my progress in future posts!

Have fun!
73 de KD0FNR


Jason NT7S said…
Glad to have assisted you with the PSK app. Hope you can get that thing transmitting and I can catch you on the air sometime.

73 de NT7S

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