RF Modulators: what Claude and GPT would buy

Two AI models chose on their own, with no web access. Nobody tested these products: this is what each one says, and how to check it.

Claude and GPT choose the same brand, RCA

In Electronics, Claude and GPT choose the same brand in 21 of 42 categories.

Claude Opus 5.5 · October 29, 2026

RCA (brand)

RCA's basic channel 3/4 RF modulators are the long-standing, widely available way to feed a composite source into a TV that only has a coax input.

Not for: Anyone whose TV has composite or HDMI inputs; connect directly instead, because an RF modulator degrades the picture.

GPT 6.1 Sol · November 10, 2026

RCA CRF907A

A straightforward choice for connecting composite video sources to older televisions through a channel 3 or 4 coaxial input.

Not for: HDMI sources, HD video, or televisions without an analog tuner.

TV analog tuning. Confirm the TV can still tune analog channel 3 or 4. A standard modulator outputs an analog NTSC signal, which a digital-only tuner will not display.
Inputs. Match the modulator's inputs to the source: composite, S-Video, or HDMI on newer digital modulators. Most basic units accept only composite video and RCA audio.
Audio. Expect mono audio from basic units, and check for stereo if it matters. Many simple modulators sum the audio to mono.
Channel selection. Use a 3/4 switch for a single TV, or an agile or digital modulator for distribution across a house. Distribution systems need channels that do not clash with other signals.

Shops seen in search results on November 5, 2026. A shop missing here may sell it too. Nothing was checked by a person.

Why is the picture snowy or wavy?

Set the TV to the same channel (3 or 4) as the modulator's switch, and pick the one not used by a local broadcast.