[OZAPRS] Is there any one using PSK63 ?

[Gerard Hill]

Hi Richard,

The FSK and PSK63 APRS signals are using different frequencies even 
though the suppressed carrier frequency (10.1476 MHz) is the same.

FSK uses tones at 1600 and 1800 Hz.
PSK63 uses 2100 Hz.

They are far enough apart not to cause mutual interference. You can see 
a waterfall spectral display of the two here:
http://wa8lmf.net/APRS_PSK63/Mix-Spectrum-Dual.gif

At the top is the PSK63 signal and in the middle is the FSK signal. They 
do not overlap and will happily coexist. You can remove one or other of 
them by using a narrow filter in your receiver such as a 300 Hz "CW" 
filter tuned to the right frequency. A narrow filter is a good idea 
anyway as reducing the noise bandwidth really helps improve the decoding 
of the FSK or PSK63 signal.

Cheers ... Gerard, VK2IO

On 20/05/2010 11:12 AM, Richard Hoskin wrote:
> Hi Ray,
>
> It good to see some experimentation with other modulations types for HF
> APRS.
>
> I’d recommend you use a different frequency other than the standard APRS
> packet frequency for PSK63 or any other type of modulation so as not to
> potentially interfere with normal 300 baud FSK APRS network traffic.
>
> You could drop down 5 Khz or so and establish a PSK63 net there.
>
> Cheers
>
> Richard
>
> VK3JFK
>
> ------------------------------------------------------------------------
>
> *From:* ozaprs-bounces at aprs.net.au [mailto:ozaprs-bounces at aprs.net.au]
> *On Behalf Of *VK2FKO
> *Sent:* Tuesday, 18 May 2010 9:47 PM
> *To:* ozaprs at aprs.net.au
> *Subject:* [OZAPRS] Is there any one using PSK63 ?
>
>
> I did see some one put out a email a little while back asking about
>
> using PSK63, but I did not see any replies.
>
> I have a beacon on 10.147.60 USB using PSK63
>
> Can any one see my beacon, and can you give me a report.
>
>
> Ray
>
> VK2FKO