The Signal and Telegraph branch is maintained by a group of members with an interest in signalling and electronics. All signalling on the Diamond Valley Railway is based on Victorian Railways prototype and practices including two position semaphore, two position light, three position light, three position search light and under construction is a new and improved version of a three position upper quadrant signal.
Both home, distant, and automatic signals are represented along with line side accessories including operating level crossings with working boom barriers still in the planning stages.
The Diamond Valley Railway has two signal boxes, representing lever operation with electric/mechanical interlocking, and switch operated relay interlocking.