High-frequency Channel Forming Equipment AVK-1 High-frequency Channel Forming Equipment AVK-3

Designed for 1/3 high-frequency telephone channels and 2/6 interconnecting channels between the dispatch station and controlled stations of the power supply lines with the voltage of 35-330 kW.

It consists of a dispatch set and a controlled station set. Each set includes an unified high-frequency terminal and a low-frequency terminal which is connected by means of two telephone pairs and can be at a distance of 5 km from each other without multiplex equipment being employed.

The low-frequency terminal design provides one input and output with resistance 600 Ohm for external telephone set.

NameValue
Operating band (overlap with step 4kHz), kHz 32-1000
Total output on-peak power, W 20
Telephone channel band, Hz 300-2000 или 300-3400
Interconnecting channel band, Hz 2400-3400
Control signal frequency, Hz 3765
Digital AGC operation range, dB 30
Gain flatness, dB 0,5
Manual attenuator operation range, dB 35
Passband attenuation, dB 52
Power supply from single phase alternating current network 220В, 50Гц

Also:

  • high frequency terminal path has a four-frequency amplitude-frequency response corrector with control limits 6 dB;
  • high frequency terminal receive path has a four-frequency amplitude-frequency response corrector with control limits 6 dB;
  • communication during setup of all the terminals available;
  • receiver selectivity while detuning at 4.3 Hz from channel band edge is not less than 60 dB, while detuning at 8 kHz — not less than 70 dB;
  • the equipment has warning system actuated in case of AGC is no longer in its operating zone;
  • automatic subscriber connection following the protocol АДАСЭ (distant automatic power system communication equipment);
  • two 100 baud internal telemetry modems which can be mounted in high and low frequency terminals;
  • two transformer inputs/outputs for external modem connection to high and low frequency terminals;
  • telephone four wire termination level 0 dB or −13/+4 dB in case of multiplex equipment is applied;
  • carrier generator frequency stability at temperature ranging from −10 to 40°C not worse than 3×10-6.

AGC — two stage. The first stage operates at pilot frequency 3765 Hz with a 2 dB step. The second stage operates within the range of ±2.5 and maintains output voltage with a step accuracy ±0.5 dB.

The АВК-1М subassembly is a single bay which contains low frequency ends and the signal conversion path.

Output power — not less than 16 W.
Peak power — 32 W

External and internal telephone channel switching bands300—2000 or 300–3400, Hz

A generator system AVK-1M (АВК-1М) enables low phase jitter which provides for higher data rate speed viacommunication channels with a lower number of errors.