Röhrenmarken / Tube Brands noch in Arbeit / still under construction
| A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
| GELOSO |
| GIBRALTAR |
| GOLD LABLE |
| GOLD SEAL |
| GOLDENTONE |
| GOLDTONE |
| GOODE TWO-O-ONE_A |
| GOULD |
| GRANDTONE |
| GRANGER |
| G.E. England |
| G.D.E.R. |
| GEMA |
| General Electric |