These electronic solid-state regulators are designed to be the most durable and efficient on the market. Many other electronic regulators do not meet these stringent criteria!

• Extremely low heat production: It can be mounted in areas with limited ventilation and high ambient temperature. This requires sophisticated support circuitry. Traditional designs and even the original mechanical regulator put out significantly more heat!¹
• High heat tolerance: Industrial grade parts are selected so the regulator functions flawlessly in high ambient temperature environments.²
• High current capability: Sustained operation at full output is not a problem!
• Survives high voltage spikes: A bad HT ignition lead can cause repetitive huge voltage spikes in the electrical system!³
• Survives reverse battery connection: Accidents happen, even to the most careful owner.
• Low RPM self-start of the dynamo: A design enhancement avoids the need to “blip” the throttle to bring the dynamo on-line. It is able to develop a couple of amps output at about 1000 engine RPM.⁴
• Small size: It easily fits in most original regulator cases. We also offer custom aluminum enclosures.

The first ADR prototype electronic solid-state regulator was made in 2009 and it is still in use and working perfectly (all hand-made, including the circuit board!). The newest version of the regulator uses the same basic design and adds extra function for even less heat production, while at the same time allowing the generator (dynamo) to self-start at very low RPM.

As an example, on my TR4A the generator (dynamo) is able to be running charge-neutral (neither charging or discharging the battery) with approximately a 15 amp load (55W headlights + tail & running lights) at 1200 engine RPM. And it able to produce the full 22 amp output from its C40 dynamo by 1500 engine RPM.

These regulators are compatible with all Lucas-type generators (dynamos). This includes the common C40, C39, and all others found on Triumph, MG, Healey, and sundry other vehicles. I recommend converting positive ground vehicles to negative ground, but a positive ground version of the regulator is in the prototype stage. The Lucas-style generators (dynamos) are found in virtually all British cars up until about 1966, and probably some used them after that. If your car has close to the stock amount of power draw, then it is certainly feasible to keep the original generator as they are high quality and will give decades of good service. If you have installed extra lighting, then conversion to LED bulbs may keep your power utilization within the range able to still be supplied by a generator (dynamo).

Contact us information on service in the US, and visit this link: Classic Dynamo & Regulator Conversions for service in the UK.

^{1 The original RB-106 mechanical regulator produces about 6 watts of heat. All the electronic regulators I have seen, including the leading electronic regulator in the UK, and the out-of-production Wilton Auto electric regulator produce at least 13 watts at 22 amp output. In an enclosed space, the temperature of the regulator will skyrocket, and this is superimposed on high ambient temperatures already present in the engine compartment. In comparison, our regulator produces no more than 2.5 watts at 22 amp output. No other regulator available for this application produces less heat than the ADR regulators}

^{2 Some components such as electrolytic capacitors have limited lifetimes at high ambient temperatures. Even those rated for 100°C have degraded lifetime at high temperature. These sorts of components are stringently avoided.}

^{3 The electronic components in our regulators are rated for voltages well above the 14 volts of automotive systems, and there are protective devices which limit the voltage seen by these components to well under their maximum voltage. Interestingly, some other electronic regulators have microprocessor control. Microprocessors are notoriously prone to damage or destruction by voltage spikes and electromagnetic interference. What happens when your regulator’s computer crashes?}

^{4 No other regulator design can come on-line sooner. It rivals the self-start capability of the original mechanical relay.}