Rede Megahertz

1983-1987
In 1981, Grupo Block emerged one of the three major bidders to Rede Gupi's concessions, which has shut down one year before due to its near-bankruptcy, the other two being Grupo Silvio Campos and Grupo Abril. The former two eventually emerged as the winners of the bidding process, with Block inheriting Rede Gupi's concessions in Rio de Sineiro (channel 6), Novo Horizonte (channel 4), Fortitude (channel 2) and Arrecife (channel 6) as well as the former TV Excelsa's frequencies in São Gonçalo (channel 9), despite the initial concerns of the Federal Government about its namesake magazine's Carnival coverage. After initially scheduled to be launched between September and November 1982, it was delayed to March 1983 and then to June 5th, 1983, when it was officially launched. The five dots in the "M" of this logo represent the network's owned-and-operated stations in those cities, while the four dots in the "Z" of this logo represent Grupo Block's subsidiaries (Block Editores, Rádio Megahertz, Megahertz FM and the network itself).

1992-1993
In 1992, Megahertz faced bankruptcy for the first time due to high production costs caused by the soap opera Rainzônia in an attempt to replicate the success of their previous soap opera Pantanal, resulting in low ratings and losing its second place to EPT, as well as the criticism for the network appealing to erotism. Under pressure, Grupo Block sold 49% of the network to Indústria Palesiana de Formulários in an attempt to keep it financially stable. However, despite the promise of bringing more investments, the network's debts started increasing, leading to delays in the payment of salaries to its employees, ending up going on strike to have their situation resolved, as well as the scrapping of equipment. After attempts from the Unified Workers' Central, linked to the Workers' Party, and the Government of Rio de Sineiro to take over the network and turn it into a non-profit network (similar to competitors TV Educativa and TVP Palésia), Grupo Block recovered the ownership of the network on April 23th, 1993 after winning a lawsuit against IPF, although at the cost of some of its founding affiliates switching affiliations to EPT or Rede Viseirantes due to its financial and social instability.

1996-1999
Since 1998, Rede Megahertz has been facing bankruptcy for the second time in its history, the first time being in 1992 and emerging from it in 1993, once more due to high production costs, aggravated by the loss of audience and core affiliates to its competitors, attempting to financially reestructure itself and its schedule to revert its situation. After the debts of Grupo Block getting worse, causing its employees to go on strike over their back pay, and failed attempts to sell the network to different parts like the Reborn in Christ Church, Editora O Dia, Grupo Abril and ironically both Central Telecord de Comunicação and Diários Associados, the network itself finally shut down later in May 10th, 1999 with its concessions being acquired by the TV Ômega consortium the day before, who already produced its Sunday variety show Domingo Total since 1998 under an outsourcing agreement, launching a transitional network (later named TVO) who then began test broadcasts in the same day and officially launched in November 1999 as the newly renamed Telerede network.