Here is a straightforward way to test ports on a local or remote system. You can even specify a timeout (in milliseconds):

function Get-PortInfo
{
    param
    (
        [Parameter(Mandatory)]
        [Int]
        $Port,
    
        [Parameter(Mandatory)]
        [Int]
        $TimeoutMilliseconds,
        
        [String]
        $ComputerName = $env:COMPUTERNAME
    )
  
    # try and establish a connection to port async
    $tcpobject = New-Object System.Net.Sockets.TcpClient 
    $connect = $tcpobject.BeginConnect($computername,$port,$null,$null)
    
    # wait for the connection no longer than $timeoutMilliseconds 
    $wait = $connect.AsyncWaitHandle.WaitOne($timeoutMilliseconds,$false) 
    
    # return rich information
    $result = @{
        ComputerName = $ComputerName
    }
    
    if(!$wait) { 
        # timeout
        $tcpobject.Close() 
        $result.Online = $false
        $result.Error = 'Timeout'
    } else { 
        try { 
            # try and complete the connection
            $null = $tcpobject.EndConnect($connect)
            $result.Online = $true
        }
        catch { 
            $result.Online = $false
        } 
        $tcpobject.Close() 
    } 
    $tcpobject.Dispose()
    
    [PSCustomObject]$result
} 

Scanning ports is now pretty easy:

 
PS> Get-PortInfo -Port 139 -TimeoutMilliseconds 1000

ComputerName    Online
------------    ------
DESKTOP-7AAMJLF   True
 

PS> Get-PortInfo -Port 139 -TimeoutMilliseconds 1000 -ComputerName storage2

Error   ComputerName Online
-----   ------------ ------
Timeout storage2      False 
 

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