Start Call
A start call is the activation step that turns on a newly created subnet’s emissions. Official documentation describes activating a subnet to begin its first emission period, after which the subnet starts distributing alpha to its participants.
References: Create a Subnet
Before and After Activation
Creating a subnet and emitting on it are separate milestones. A freshly registered subnet exists on the network but does not yet emit. The start call begins its first emission period, and from that point the documentation notes that the subnet creator starts accumulating emissions and the subnet’s token economy shows a non-zero emission amount.
References: Create a Subnet, Emission
Place in the Subnet Lifecycle
The start call separates subnet creation from the start of emissions. That gap lets a subnet be registered and prepared before it begins distributing alpha, rather than emitting from the instant it is created. Once activated, accumulated rewards are distributed to participants each tempo through consensus.
References: Create a Subnet, Emission
Relationship to Participation
Activation is what makes participation worthwhile. With emissions running, the documentation explains that miners and validators can register and run on the subnet and earn from the emission flow. Before the start call there is no emission for their work to draw from, so the activation marks the point where the subnet becomes economically live.
Reference: Create a Subnet
Development Stage Context
The Introduction to Bittensor describes subnet development as moving from localnet to testnet and then mainnet. For a start call, that sequence changes which network a reader should assume when asking whether a subnet is emitting.
In localnet, subnet registration and activation can be tested in an isolated environment. Localnet activation state does not represent production emission timing on live subnets.
On testnet, a start call can be issued on a shared non-production network. Testnet activation and emission history are separate from mainnet subnet state (Create a Subnet).
On mainnet, a start call concerns live production subnet activation and the first emission period on the selected netuid.
The Bittensor Networks reference separates mainnet, testnet, and localnet. An activation example from one environment should not be read as describing emission status on another network.
Relationship to Yuma Consensus
Start Call and Yuma Consensus describe related parts of Bittensor’s incentive system. Yuma Consensus is the on-chain process that aggregates validator weight signals within a subnet into miner incentives and validator dividends, applying consensus clipping, bonding, and emission calculation (Yuma Consensus).
For readers, start call names a specific part of that incentive picture, while Yuma Consensus names the consensus process that turns validator weights into the resulting incentives and dividends.
Reader Boundary
This page defines the concept at a high level. It does not report whether a particular subnet has been activated, when its start call happened, or its current emissions. Those are live chain state and should be checked for the relevant netuid, for example netuid 1. The article describes the role of the activation, not a procedure to perform it.
Reference: Create a Subnet
Subnet Registration Precedes Activation
Official Create a Subnet documentation treats subnet registration and the start call as separate steps. A participant first registers the subnet on Subtensor, paying the documented registration cost in TAO, and only later issues the start call that begins emissions.
That ordering keeps economic setup separate from emission timing. Registration establishes the subnet’s identity and owner on chain, while the start call is the later switch that turns on the first emission period for that netuid.
References: Create a Subnet, Glossary: Subnet
Alpha Issuance Begins at the Start Call
Understanding Subnets explains that each subnet issues its own dynamic token, referred to in the abstract as that subnet’s alpha. The start call marks when that per-subnet issuance path becomes active rather than when the subnet record is first created.
Before activation, the subnet can exist without distributing alpha to participants. After the start call, official creation guidance notes that the subnet creator begins accumulating emissions and the subnet’s token economy shows a non-zero emission amount tied to ongoing subnet activity.
References: Understanding Subnets, Create a Subnet
Tempo Settlement Follows Activation
Once emissions are running, Emission documentation describes rewards accumulating during each subnet tempo and being distributed through Yuma Consensus at the interval boundary. The start call therefore begins both alpha issuance and the tempo rhythm that groups participant payouts.
That keeps activation vocabulary separate from creation vocabulary. Registration answers whether the subnet exists on chain; the start call answers when its first tempo-sized emission and distribution cycle can begin for miners, validators, and stakers who register afterward.
References: Emission, Glossary: Tempo