SWISS-PTC II HF-Radio Modem

Swiss PTC-2

Description :

The SWISS-PTC II is a state-of-the-art DSP based HF-modem designed for professional applications. The SWISS-PTC II connects to PC-compatible laptop or desktop computers. The modem uses advanced modulation and coding methods resulting in extremely reliable data transfer even during poor HF-propagation conditions. Experience of our customers has shown, that the SWISS-PTC II outperforms most other HF-modems under typical HF-propagation conditions. The SWISS-PTC II modem is still transferring error-free data when other modems give up.

Due to the advanced frequency tracking capabilities, the SWISS-PTC II can be connected to a large variety of HF-radios.

The SWISS-PTC II is the choice for efficient and reliable transmission of e-mail and data over HF-Radio links.
The SWISS-PTC II modem uses extremely robust modulation methods, convolutional coding and interleaving. This allows data communications even over HF-channels with very poor propagation conditions.
The SWISS-PTC II modem can be connected to a large variety of HF radios.

Data throughput 589 Bit/sec uncompressed data, equivalent to 1000 Bit/sec plain text using the automatic data compression.
Under typical HF propagation conditions, experience has shown, that the SWISS- PTC II is very often faster than so called '6000 bits/sec modems'
Required S/N ratio Maintains reliable commiunication down to a S/N ratio of minus 18dB (@ B = 4KHz).
Required bandwidth 450 Hz (at -50dB)
Modulation Staggered 2-tone Differential Phase Shift Keying using 2-16 phase differences - Raised cosine shaped pulses resulting in a crest factor of 1,45
Channel coding Convolutional code (k-9) combined with full frame interleaving, Viterbi decoding with soft decision. Code rate adapted to applicable mode, between 1/2 and 7/8.
Compression Huffman or Pseudo-Markow plus run- length encoding, selfadaptive (optimizing)
Protocol and adaptivity Advanced half-duplex hybrid ARQ with memory. The modem parameters (code rate, number of DPSK levels etc.) continuously adapt to the varying link conditions
Frequency tracking Initial offset: up to +/- 80Hz Drift: up to 10Hz/min
Compatibility Fully compatible to CCIR-476/625 SITOR and PTC-I systems with automatic switching - Public/Non- Public same as PTC-I
Selective call 3 to 8-digits alphanumeric addressing
Front panel displays Tuning LED-bar, Connect, Sending, Error, Request LEDs
Rear panel connectors Radio port, Data port, PR port, Control port & Power switch
RX audio input RX audio input
TX audio level Software adjustable between +5dBm and -35dBm
Radio port Sub-D-15M providing balanced and unbalanced TX and RX audio, PTT (open collector), FSK (TTL), Scan- Stop, GND, +DC supply input and 3 spare pins
Serial interface (data port) Sub-D-9F connector, 300 - 115 kBaud
Supply power +9VDC to 20VDC (current at 13,5VDC = 250 mA)
Dimensions Aluminium extrusion cabinet 210 * 170 * 55mm / 1,2Kg

Euro Radio System

Tel : +33 (0)1 39 31 28 00/ Fax : +33 (0)1 39 31 27 00
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