Etronix Power Cap Receiver Voltage Stabiliser ET0077

Overview

The Etronix Power Cap ET0077 is an essential electrical accessory for any RC enthusiast in the UK who runs high-power, high-current servos in their models. Whether you're operating a brushless RC car, a scale crawler, or any radio-controlled vehicle that demands consistent receiver performance, voltage drop can be a frustrating problem that compromises your radio system's reliability. This compact power cap from Etronix solves that problem elegantly, ensuring your receiver maintains the correct operational voltage at all times, even under the demanding conditions created by powerful servos drawing significant current.

For builders and RC hobbyists across the UK looking to enhance electrical stability in their models, the Etronix Power Cap represents a straightforward, affordable solution that requires no complex installation or modifications to your existing setup. Simply plug it into any open channel on your receiver and enjoy improved voltage regulation without any fuss. It's the kind of upgrade that makes a real difference to how smoothly and reliably your RC car or truck performs, particularly when you've invested in quality high-current servo equipment.

The Power Cap is designed with simplicity and effectiveness in mind, making it equally valuable whether you're running a ready-to-run RC vehicle from the box or a carefully tuned competition machine. By addressing voltage drop issues at the receiver level, this component supports consistent operation of your entire radio system, giving you the confidence to push your RC model to its limits without worrying about servo dropouts, glitching, or erratic behaviour caused by insufficient power delivery.

Key Features

• Voltage Stabilisation at the Receiver — This power cap helps maintain the correct operational voltage at your RC receiver, which is critical for stable servo operation and consistent radio control performance. When high-power servos draw significant current, voltage can sag, but this device counteracts that problem directly at the source.
• Reduces Voltage Drop with High-Current Servos — If you're running powerful servos that pull heavy current during operation, voltage drop becomes a real issue. The Etronix Power Cap addresses this directly by providing electrical stabilisation, ensuring your servos respond quickly and reliably without hesitation or glitching.
• Simple Plug-In Installation — No soldering, no complex wiring, no technical expertise required. Simply plug the unit into any open channel on your receiver and you're done. This makes it an easy add-on upgrade for builders of all skill levels, from beginners to experienced competitors.
• Universal Receiver Compatibility — Because it plugs into a standard receiver channel, the Power Cap works with virtually any RC receiver you're already using, whether you run Spektrum, Futaba, Hitec or any other major brand.
• Compact and Lightweight — The Power Cap is small enough to fit easily into any RC model without taking up valuable space or adding significant weight to your chassis.
• Safe Input Voltage Range — Rated for a maximum input voltage of 16 volts, the Power Cap safely handles everything from 2S LiPo packs (7.4V nominal) through to 5S setups (18.5V nominal), making it compatible with the vast majority of RC vehicles on the market.

Technical Performance

The Etronix Power Cap ET0077 is engineered to address one of the most common electrical problems encountered in RC vehicles: voltage sag at the receiver during high-demand servo operation. When servos draw large currents—particularly during aggressive turning, acceleration, or load-bearing operations in crawlers and scale models—the voltage available to the receiver can drop significantly, causing erratic behaviour and loss of control responsiveness. This power cap uses capacitive technology to smooth and stabilise the voltage supply, maintaining the clean power delivery that your receiver and servos demand for precise, reliable operation. The device is built to work within the safe voltage envelope of 16 volts maximum input, making it suitable for any standard RC battery configuration from small 2S LiPo packs in lightweight race buggies through to the more substantial 5S and higher setups used in larger scale models and rock crawlers. The engineering is straightforward but effective: it stores electrical energy and releases it to compensate for voltage drops, acting as a dedicated power reserve for your receiver circuit. Installation requires no modifications to your existing wiring or receiver setup, making it a non-invasive upgrade that can be fitted in minutes and removed just as easily if needed.

What's in the Box

• Etronix Power Cap ET0077

Frequently Asked Questions

• What does a receiver power cap actually do? — A power cap is a capacitor that stores electrical energy and releases it to compensate for voltage drops in your receiver power supply. When servos draw large currents, voltage naturally sags, which can cause servo lag, glitching, or erratic behaviour. The power cap smooths out these voltage fluctuations by providing an instant supply of electrical energy, maintaining stable voltage at your receiver even under heavy servo load. This results in faster servo response, more precise control, and improved overall radio system reliability.
• Is the Etronix Power Cap suitable for beginners? — Absolutely. This is one of the easiest upgrades you can make to an RC vehicle. There's no soldering, no complex wiring, and no technical knowledge required. Simply plug it into any open channel on your receiver and you're done. Even if you've never modified an RC car before, you'll have this installed in under a minute. It's perfect for anyone looking to improve their setup without tackling complicated electrical work.
• What battery voltage can this power cap handle? — The Etronix Power Cap is rated for a maximum input voltage of 16 volts. This makes it compatible with 2S LiPo packs (7.4V nominal), 3S packs (11.1V nominal), 4S packs (14.8V nominal), and even 5S packs (18.5V nominal) that stay within the safe operating range. However, always check your battery voltage before installation to ensure it doesn't exceed 16 volts. Most standard RC vehicles will fall well within this safe operating envelope.
• Will this power cap work with my receiver? — Yes, the Power Cap works with virtually any receiver that has a standard receiver channel connector. Whether you use Spektrum, Futaba, Hitec, or any other major brand receiver, this device will plug straight in. Just connect it to any available channel that isn't being used by a servo or other device, and you're all set. The universal design makes it compatible with nearly every RC vehicle in circulation.
• Does the power cap need any special setup or configuration? — No configuration needed whatsoever. This is a passive electrical component—there are no settings to adjust, no firmware to update, and no switches to configure. Simply plug it in and it works immediately. The voltage stabilisation happens automatically without any intervention from you.
• What type of RC vehicles benefit most from a power cap? — Any RC vehicle with high-power servos will benefit, but particularly scale crawlers, competitive off-road buggies and trucks, and high-current servo setups. If you've ever noticed your steering servo lagging when another servo is moving simultaneously, or if you experience glitching when all your servos are working hard, a power cap will make a noticeable difference. They're essential for serious competitors and builders pushing their RC cars to the limit.

Why Buy from RC Model Shop?

RC Model Shop is a trusted UK RC retailer and authorised dealer for all the brands we stock, including Traxxas, ARRMA, Losi, FTX, Hobbywing, Spektrum and more. Based in Walsall, we have a physical store where customers are welcome to come in, view products and purchase in store. Whether you are a seasoned competitor, a weekend basher, or just discovering the world of RC for the first time, our team of experienced RC enthusiasts is here to help you find the perfect setup and provide ongoing support. Order the Etronix Power Cap ET0077 today with confidence, knowing you are buying from an authorised retailer with genuine products, expert knowledge and a commitment to customer satisfaction. Shop online or visit us in Walsall — we look forward to helping you get the most out of your RC experience.