Specifications
All parts 3D printed from PETG material, UV resistent and water proof.
LHCP Variant | RHCP Variant | |
Radiating Element | 3 turn left handed helix, 3.5mm copper wire | 7 turn right handed helix, 3.5mm copper wire |
Reception configuration | Consumer type satellite dish | Direct reception |
Mounting Option | Mounts in standard 40mm LNB clamp (for offset dishes) Universal mounting via 3 M4 bolts (for prime focus dishes) | Universal mounting via 3 M4 bolts |
Dimensions | Length: 186mm, Diameter: 180mm | Length: 374mm, Diameter: 180mm |
Connector | N-type | N-type |
Applications | Reception of geostationary satellite services, e.g. Inmarsat, Iridium, digital telephony / data, digital weather pictures | Reception of geostationary and LEO satellites when mounted to el/az-rotor |
Availability | nolle.engineering (webshop) | nolle.engineering (webshop) |
RF Performance
LHCP, 3 windings





RHCP, 7 windings




Concept Renderings



RHCP Prototype



LHCP Prototype

Use Case
Architecture
See below an example on how to setup your L-Band receiver station. Signal is filter, amplified and digitized by software defined radio then provided to software receiver running on your local PC.
Filtering is optional, it might be necessary depending on your local RF environment (Wifi, LTE presense).

Components
Components | Description | Source (incl. 3rd party and affiliate links) |
L-Band Antenna | LHCP or RHCP as per your preferences | nolle.engineering (coming soon) |
N-Type to SMA adapter | Adapter from antenna to filter / LNA (N male to SMA male) | |
Bandpass Filter | Blocking any interference from Wifi, LTE etc. improving signal strength | GPIO LABS 1525 to 1559 MHz Bandpass Filter![]() |
LNA (bias tee) |
Low Noise Amplifier (LNA) and Saw Filter Module 1542MHz centre frequency Powered via SMA output, requires SDR with bias-T. | |
LNA |
Low Noise Amplifier (LNA) and Saw Filter Module 1542MHz centre frequency Powered via micro USB 5V | |
SDR (bias tee) | Software Defined Radio, including bias-T required to power LNA | |
SMA Interconnects | SMA male to SMA male connecting between components | |
SDR# | SDR Software | https://airspy.com/download/ |

Left: 3-turn LHCP on 1.5m prime focus dish (click to enlarge) vs. Right: 7-turn RHCP (direct reception)
Decoder Software
A list of popular INMARSAT and others deconding software packages:
- https://tekmanoid.com/egc
- https://github.com/jontio/JAERO/releases
Web SDR Demo
23.10.2022: I am operating a live web SDR with the LHCP version on a 80cm offset dish. It is located at JN58UA and currently pointed towards Alphasat tuned to 1541.1 MHz with 2MHz bandwidth.
Click on the image to test the receiver. It is fully interactive:
