vu3dxr
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DIY – 137 Mhz V-dipole antenna for weather satellites reception
D.Prabakaran VU3DXR
A V-dipole for NOAA weather satellites on 137 MHz has been published by 9A4QV and it seems to get very good results. The designed antenna works at frequency 137 Mhz with omnidirectional radiation pattern.
The length of the each leg should include the connecting wire’s length up to the coaxial connector or coax. For my case connecting wire’s length is around 6 cm for convenience. Here in my case, PVC end cap acted as antenna elements mount, which is structurally stable than electrical terminal block.
I have used the following materials:
⦁ PVC pipe – 2 inch diameter
⦁ PVC pipe – 2 inch end cap
⦁ Aluminium or brass elements(one end threaded) – 2 nos each length 530mm
⦁ 8mm Brass stand off nuts and bolts – 3/4 mm size – 2 nos
⦁ BNC female connector adopter
⦁ solder lugs with 6cm wire soldered – 2 nos
Procedure
1. Fix brass stand off nuts on PVC end cap at 120 degree apart using bolts along with solder lugs.
2. Insert both antenna elements into brass stand off nuts and firmly screwed it.
3. wires from solder lugs connected to BNC female connector adopter
4. Fix PVC end cap on top of PVC pipe.
5. The length of the each leg should include the connecting wire’s length up to the coaxial connector or coax plus length of stand off nut.
6. Stand off nut length should be minimum 8mm
V DIPOLE ANTENNA 137 MHZ
With this antenna, i captured two NOAA satellite passes just above my location. Images are given below. During second pass, another sat meteor-m2-2 caused lot of qrm after 75% of decoding.
My nanovna sweep show resonance at 133mhz,which near to required 137 mhz. i need to trim antenna little bit to obtain resonance at 137.5mhz.
D.Prabakaran VU3DXR
A V-dipole for NOAA weather satellites on 137 MHz has been published by 9A4QV and it seems to get very good results. The designed antenna works at frequency 137 Mhz with omnidirectional radiation pattern.
The length of the each leg should include the connecting wire’s length up to the coaxial connector or coax. For my case connecting wire’s length is around 6 cm for convenience. Here in my case, PVC end cap acted as antenna elements mount, which is structurally stable than electrical terminal block.
I have used the following materials:
⦁ PVC pipe – 2 inch diameter
⦁ PVC pipe – 2 inch end cap
⦁ Aluminium or brass elements(one end threaded) – 2 nos each length 530mm
⦁ 8mm Brass stand off nuts and bolts – 3/4 mm size – 2 nos
⦁ BNC female connector adopter
⦁ solder lugs with 6cm wire soldered – 2 nos
Procedure
1. Fix brass stand off nuts on PVC end cap at 120 degree apart using bolts along with solder lugs.
2. Insert both antenna elements into brass stand off nuts and firmly screwed it.
3. wires from solder lugs connected to BNC female connector adopter
4. Fix PVC end cap on top of PVC pipe.
5. The length of the each leg should include the connecting wire’s length up to the coaxial connector or coax plus length of stand off nut.
6. Stand off nut length should be minimum 8mm
With this antenna, i captured two NOAA satellite passes just above my location. Images are given below. During second pass, another sat meteor-m2-2 caused lot of qrm after 75% of decoding.
My nanovna sweep show resonance at 133mhz,which near to required 137 mhz. i need to trim antenna little bit to obtain resonance at 137.5mhz.
