Sepura SC21 Extended Helical Antenna 380-430MHz (Green)

Genuine Sepura extended helical antenna for the SC21 TETRA hand-held radio. Covers the 380–430MHz UHF band. Identified by green colour coding on the base of the antenna. Length approximately 51mm (excluding screw fixing).

The SC21 uses an M6 screw connector — note this is different from the SMA male connector used on the STP8000/STP9000/SC20/SC23 series. Antennas are not interchangeable between ranges.

Selecting the correct SC21 antenna

Antennas are selected by operational frequency band and are colour coded on the base. Nominal gain figures are measured in free space at resonance and will degrade when used close to the body.

Extended Helical Antennas (>-1dBi)

Colour	Frequency	Part No.
Green	380–430MHz	310-00014
Yellow	420–470MHz	330-00016

Quarter Wave Antennas (>0dBi)

Colour	Frequency	Part No.
Purple	380–470MHz	310-00015
Orange	806–870MHz	350-00007

Technical specifications

• Nominal impedance: 50Ω
• VSWR at resonance: ≤1.5:1
• Connector type: M6 screw
• Operational temperature: -20°C to +55°C (usable range -30°C to +75°C)
• Length: approximately 51mm (excluding screw fixing)

Part number: 310-00014. Replaces previous part number 300-01931.

Authorised Sepura Dealer: Showcomms is an authorised Sepura reseller. We supply individuals and organisations who need genuine Sepura products outside of their normal procurement route — whether that’s a one-off spare, an accessory not covered by your framework, or an officer assigned away from their usual radio pool who needs a charger or battery locally. If you are unsure whether we can help, please get in touch before ordering.