SED of 4C 23.56. Black solid line shows best fit total model, green dashed line is synchrotron power law for the radio core, dotted line indicates the AGN component. The colored data points are sub-arcsec resolution data and black ones indicate data with low spatial resolution. Green pentagons are emission from the radio core, cyan diamond from ALMA band 3, blue triangle indicates the ALMA band 3 3σ upper limit. Filled black circles indicate detections (> 3σ), downward pointing triangles the 3σ upper limits (Table A.1).