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Hello everyone, I’m back again to review an accessory that I think is particularly useful for those who use a gyroscope on their aeroplane or for anyone who simply wants to monitor flight data via telemetry. Today I’ll be talking about the new “PowerBox GPS-V” satellite device, which represents the latest evolution – updated in both software and construction – of one of the most popular accessories among model aircraft enthusiasts. I have personally tested this sensor on my 3-metre Fox FMS glider, fitted with a 10-channel Jeti REX Assist receiver. I will divide my review into sections covering the various specifications.
Hardware and Technology: what’s inside the GPS-V
The sensor, like previous versions, is extremely compact (60 x 18 x 15 mm) and lightweight (14g) and uses industrial-grade components that guarantee superior performance compared to standard consumer products. The main features are, in order:
• Helix (radial) antenna: Unlike older flat antennas, this design ensures reception even when the model is in extreme flight attitudes (barrel rolls, spins, inverted flight).
• U-blox MAX10 chip: Enables a fast satellite ‘fix’, proving effective even in partially obstructed conditions. My outdoor test recorded a time of between 25 and 30 seconds to lock onto satellites and become operational.
• Doppler speed: in the GPS-V sensor, speed is not calculated using the distance between two points (the classic but slow method), but by exploiting the Doppler effect on satellite signals, eliminating any delay (lag). The Doppler effect on satellite signals is the apparent change in the frequency of a radio signal (electromagnetic wave) emitted by a moving satellite relative to a ground-based receiver (or vice versa).
• MEMS (Micro-Electro-Mechanical Systems) Barometric Sensor: This is a very high-resolution hybrid system that combines GPS data for absolute altitude and the barometer for relative altitude, with an accuracy of approximately 10 cm. Its operation can be summarised as measuring atmospheric pressure and converting mechanical deformations into electrical signals; the sensor contains a sealed vacuum chamber beneath a silicon membrane.
• Compatibility and Protocols (see table)
The device is Plug-and-Play (accepts voltages from 4 to 9 volts) and automatically recognises the radio protocol (Core, Jeti, Futaba, Graupner, etc.) as soon as it is connected. However, this Powerbox GPS-V, at least in my Jeti 10 Assist receiver to which I paired it, required connection via the E1 (Exbus) port, whereas it was not detected by the receiver when connected to the traditional Ext port (the input designated for the Serial bus/sensor). In the table shown in the photo, I have included some technical notes on compatibility.
Practical Tips for Installation and Flight
To get the most out of the GPS-V, it is advisable to follow some precautions outlined by Powerbox but which also stem from practical experience: 1) Positioning: If possible, keep the sensor at least 5–10 cm away from the Assist receiver to avoid electromagnetic interference or resonance. 2) Shielding: avoid covering the antenna with carbon fibre materials and always point it towards the sky. 3) Barometric pressure: do not expose the sensor to direct airflow (propellers, fans or fuselage air intakes) as this would cause false changes in altitude. 4) Stall management: remember that the GPS measures ground speed; with a strong tailwind, the aircraft could stall even if the indicated speed appears high. 5) Jeti safety: In my case, as I have all Jeti receivers and DS16s, care must be taken, in the event of a loss of GPS signal, regarding the possibility that the telemetry might read ‘0 km/h’, causing the gyro mixer to go to maximum. It is essential to set a fail-safe value (e.g. 30–40%) to maintain stable flight.
Conclusions
The Powerbox GPS-V sensor currently has few competitors on the market (you can count them on the fingers of one hand): there are similar devices, but they do not include all the features of this Powerbox in a single unit. Some offer the option of adding external barometric sensors but use older-generation GPS. In short, I believe that today this GPS-V could become the benchmark for those flying jets, scale models, aerobatic models or gliders. It is a robust, well-shielded unit designed to last for years even in harsh environments (turbine heat, combustion engine vibrations). Personally, I still have the first Powerbox GPS sensor in one of my models, and after all these years it’s still doing its job. Finally, I’d like to point out that the firmware can be updated via the ‘Powerbox Terminal’ app and the dedicated USB interface, as is already the case for all PBX devices.
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