MINIDSP POCKETADC ADC Converter ES9821Q RCA to Coaxial / Optical Toslink 24bit 192kHz - reviews - There are 2 reviews.

Elevating FM Radio: Integrating Teac PD-301-X with Topping E70 Velvet & B200 for Audiophile Sound
I have a Teac PD-301-x FM tuner with excellent sound but only an analog RCA output from the FM Radio. So, to have its sound in my HiFi audio system, I added PocketADC into the chain, which looks like this now: Analog FM signal from Teac PD-301-X → PocketADC → SPDIF → Topping E70 Velvet (DAC) → Topping B200 (amplifier) → Dynaudio Emit 20 speakers. PocketADC is transparent, and now I can enjoy excellent FM Radio quality from my nice Teac tuner.
I selected 48 kHz as the sampling rate because the source signal is analog FM radio, which has a limited frequency range—typically up to around 15 kHz. A 48 kHz sampling rate comfortably captures the full audio bandwidth of FM broadcasts without unnecessary overhead. I did not see any heat from pocketADC. Also, I use a linear power supply, Keces P6, which also powers my Teac FM Radio component.

Excellent box
I have a soundbar that lacks of any analogue inputs. Using this device I can connect my old AM/FM tuner to it. The build and sound quality is excellent