| Type | Substitutes | Base Diagram |
|---|---|---|
| 506 | RGN1054, TV80, G470, PV495, DW2X, U10, W6, RE4100, V2, D3-50B, 1823, 4619, DE2, G490, R4100, NVD3, VG240, R1054, 412BU, 4R1_Ultron, DB_Astron, DR40, DW2_Mullard, E4D, G450_Splendor, GA24, GL4/1, GN24, LG4150, Mikrotron, R0437, V6, V62_SIF, VG410, VG4100, W462_Six-Sixty | |
| Web References | 506 (Philips) @ Franks Electron Tubes? 506 (Philips) @ Franks Electron Tubes? 506 @ Radiomuseum | |