SCS PTC-IIex, Manual

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16 History
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and efficient source coding. Due to the advanced signal processing methods applied,
PACTOR-III provides outstanding performance under poor and moderate signal
conditions. As PACTOR-III also achieves very high throughput rates under good signal
conditions, it is well-suited to HF channels with good SNR and low signal distortion as
well. During the development of PACTOR-III, high importance was attached to
compatibility with ordinary SSB transceivers (using standard 2.2-2.4 kHz wide IF-filters).
Therefore, PACTOR-III can achieve its maximum speed with using unmodified, common
SSB transceivers. The occupied bandwidth is around 2200 Hz.
Thus PACTOR-III is the ideal means of fast and reliable data communication over (the
sometimes difficult medium) HF-radio. The new protocol is fully backwards compatible
to existing PACTOR-I/II networks.
In summer 2003 the PTC.-IIex suceeded the PTC-IIe. Although both models nearly not
differ from their outer appearance, in the inside the PTC-IIex has been deeply reworked.
The PTC-IIex comes with a more powerful DSP section, a TXCO stabilized oscillator, a
better power supply and with 2 MB of static RAM.
As an answer to the increasing demand for a modem with USB connection,
SCS
introduced the PTC-IIusb in the mid of 2005.
The ease the use of the PACTOR-IP-Bridge, the same time
SCS
introduced the PTC-
IInet. This unit is a neat combination of a HF radio modem with a miniature Linux
computer with Ethernet connection, all fitting inside the modem enclosure itself.