Can Roku tune analog VHF Channel 3?

For an old style TV box, the has modulated output on Chan 3? Or is the tuner DTV ATSC only?

You don’t specifically ask anything…

Where’s the antenna support on streaming-TV boxes?

That’s because Roku offers no way to connect an antenna directly to its players.

Roku has no* input or tuner for television channels 3 - 49 or 68.

Sorry, I meant from the RF antenna side. If a band pass filter introduces an analog signal on VHF 3/4 from an old cable box.

The Tablo’s tuner is ATSC only. You can’t record an old analog NTSC signal with it.

As noted by @FlyingDiver, https://www.tablotv.com/products/ click on any OTA DVR

2 Over-the-Air ATSC Tuners

or

4 Over-the-Air ATSC Tuners

Near the bottom of each page… not exactly what you asked, but similar:

Can I record cable or satellite signals with Tablo?

No. Tablo is designed to record and stream Over-The-Air (OTA) broadcast signals from ATSC TV antennas. We do not support recording from cable or satellite signals, cableCARDs, or clear/unencrypted cable (QAM).