Saturday, December 31, 2011

Propeller on 30m QRSS - Cont'd

My 30m Propeller Beacon is now on the air, a low pass filter was built and attached at the output pin and ground. The output of the filter goes to a 30m vertical via the SMA connector.

The filter was designed with the help of AADE Filter Design Software V4.5.

AADE - 30m Low Pass Filter Design

The Homebrew PCB was designed with Inkscape Graphics Program and produced using the Fab-in-a-Box Toner Transfer Method.
Filter PCB's Ready to Load Parts
Note to self: My Tinnit solution must be getting a little weak.

Low Pass Filter Ready to be Connected
to the Propeller Micro Processor and the Antenna
I have not tested the frequency response of the filter, or attempted to measure actual harmonic attenuation yet, but I plan do so in the next few days.

Now to see if this beacon can be heard at any of the QRSS Grabber Stations, maybe at KK7CC.


I plan to do more Propeller QRSS programming, I want to implement QRSS Slash Code for my station ID. Dots are send as a "/" and Dashes are "\". Note: a Morse slash character is not actually sent, it is the slant of the visual line on a QRSS Grabber that is decoded. Each slash (dot or dash) is sent for 3 seconds, as QRSS3 SlashCode mode (the default speed). For QRSS6, a dot is sent for six seconds.

My call WA0UWH in Slash Code would appear as: "/\\ /\ \\\\\ //\ /\\ ////", which is sent faster than normal visual code sent on QRSS. My call with 25 slashes (20) and spaces (5) would only take 75 seconds to be sent (one slash and space are 3 seconds).  There are no spaces within a sent character, only one slash time between characters, three between words.

In normal QRSS3 CW my call would take 165 seconds to send. That is; (2+1+5+1+1) = 10 dashes, (1+1+2+1+4) = 9 dots, and 5 spaces. That is  ( (10 × 3) + (9×1) + (5×3) ) × 3 = 162 seconds. Slash Code represents a 53.6% savings over normal QRSS CW code (for my call). At this very slow speed every second counts.


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