Globe Telecom Inc. (Globe) on Thursday backed the National Telecommunications Commission’s (NTC) recent ban against the sale of SMS or text blasters online as it warned the public against the use of such equipment, including illegal signal boosters and jammers.

In an advisory, Globe said such equipment are intended to be used “during extreme periods of disaster” and can cause “widespread interference.”

“These network disruptions include slow or failed connections, dropped calls and voice quality issues and even loss of cell phone signals,” Globe said.

Illegal signal boosters, it said, come in the form of indoor or outdoor antennas or wireless adapters that boost network coverage and signal by “hogging bandwidth” from a cell site.

“As a result, such devices interfere with airwaves and interfere with mobile signals for other customers within the immediate vicinity of the booster and served by the interfered cell site,” Globe said.

On the other hand, it said signal jammers “totally block” cellular signal to prevent the use of mobile services.

These, it said, are used in venues such as concert halls, theaters, or places of worship to prevent disruption and in high security areas as prisons.

“However, signal jammers can also be used to block cell signals that can disrupt critical service in the case of disaster relief and rescue operations or even disrupt automated elections which rely on cell signals at polling precincts,” Globe said.

The NTC, it said, has banned the sale of these devices since 2013 through NTC Memorandum Order No. 01-02-2013 entitled “Prohibition of Portable Cellular Mobile Repeater and Portable Cell site Equipment.”

It said routine scanning for such illegal devices are regularly conducted and results are passed on to the NTC for “appropriate action.”

On Wednesday, the NTC issued show-cause orders to Facebook Marketplace, Lazada, and Shopee to immediately stop the sale of text blasters.

Such equipment is used in political campaigns to promote candidates or gauge the support of the public through polls.