GB3NQ

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GB3NQ

The ATV Repeater NoV Holder is Kevin Francks M0BFB.

 

Stations transmit digital pictures on 2m, 70cm and 2m and receive television pictures using the 23cm band.

 

Stations using GB3NQ may use relatively cheap 23cm transmitters and receivers using one of the Portsdown or Minitioune/Ryde projects available from the BATC (British Amateur Television Club) or suitable DVBS-2 satellite set top boxes -check suitability before purchase. https://batc.org.uk/

 

The input frequency is 146.5 Mhz, 437Mhz and 1249 MHz and the output 1316 MHz with a symbol rate of 2000 and an FEC 4/5 DVBS-2. Although GB3NQ has audio through, stations often use talkback on the 2 metre frequency of 144.750 MHz or via GB3NC repeater on 145.725Mhz.

 

The new digital repeater electronics were constructed by Paul G6MNJ and Keith G0KTD using British Amateur Television Clubs Portsdown transmitter and 3 Ryde receivers all based around a Raspberry Pi 4.

 

A 150 watt power amplifier is driven by a 18 watt pre amplifier, both run considerably under power to remain linear - a must for digital ATV.

 

GB3NQ runs in Beacon mode between Mid day and 9Pm when it plays out a video for 30 minutes. When running between 10am and 10pm (10am to 10pm weekends and midday to 10pm in the week) it may be accessed at any time with a s valid digital television signal on 2m, 70cm or 23cm.This would be a symbol rate of 333Ksymbols/s on 2m or on 70cm and 23cm symbol rates of 333, 1000 or 2000 Ks/s.

 

The repeater transmits on 1316MHz 1500Ks/s FEC 4/5 DVBS-2.

 

GB3NQ was originally constructed by two local amateurs. Maurice G3WKF and John G0VDU. Maurice, a mechanical engineer, made the high quality filters for the input and output of the repeater and also the 4 faced lantern antennas required for the transmitter and receiver which are still in use today.

 

GB3NQ can be live streamed by using the link below

https://batc.org.uk/live/gb3nq