Custom Electronics

Here you can find descriptions about all the electronics I design and use for my own projects. I have been working in the electronics field since the early 1980's. Most of the time when I need some simple device, or a gizmo that is just not on the market, I design and build my own. It is another hobby I enjoy, and also it became my career. If you have a need for something, or maybe just a question, send me an email and I'll do my best to help.

Battery Voltage Mixer

The Battery Voltage Mixer provides two separate functions at the speed of light:

First, it allows you to use two separate battery packs to power your receiver, or other on board electronics. This provides a redundant power system to help protect your prized aircraft or other vehicle. There is also zero time delay switching from one battery pack to the other due to the simple diode design. There are no relays or other slow electronic monitoring circuits used.

Second, when used with A123 2S battery packs you can power your receiver and servos without the use of an expensive regulator. This is for use with systems using 6 volt servos. HV servos do not need this.

There are a two options available.

Option 1: The Dual Battery Voltage Mixer. This unit has a dual battery input. It can be ordered with a standard diode (~0.7 volt drop), or a Schottkey diode (~0.35 volt drop), or with one of each. Using two different voltage drops will force one battery to supply power while the other is just used for standby in case the first battery fails for some reason. Using identical diodes will power your system from both batteries equally, but still provides the failsafe power if one battery should fail.

Option 2: The Single Battery Power Regulator. This unit has a single battery input. It too can be ordered with a standard diode, or a Schottkey diode.

Voltage examples:

Exp 1. If you are using a 2S A123 pack. This will provide a typical voltage of 6.6 volts. Using the Schottkey diode will give you a nominal voltage of 6.25 volts, (6.6V - 0.35V = 6.25V). Using the standard diode will give you a nominal voltage of 5.90 volts, (6.6V - 0.7V = 5.9V).

Exp 2. If you are using the old standard 4 cell NiCad or NiMH packs, you would only want to use the Schottkey diodes. Otherwise you would drop too much voltage to your receiver and servos. You would have a nominal voltage of 5 volts,(5.0V - 0.35V = 4.65V). In this setup you would simply be using the Battery Voltage Mixer as your reduntant power system.

Dual Battery Power Regulator Mixer

Single Battery Power Regulator

Operating Instructions: All you really have to do is get both your battery packs plugged in, or switched on, within 20 seconds of each other. At 20 seconds the DBB records each battery's voltage state. You should only see the green flashing led indicating you are ready to fly. If you see either red led flashing it means you eer did not get both battery packs plugged in within 20 seconds, or you have a dead battery.

Signal / Power Mixer

The signal power mixer is used to combine the signal from the receiver with the power directly from the battery, or separate voltage regulator. This is a must for high power servos when you don't want to pull all that high power through the receiver servo connection. The signal power mixer is also a must when using high current draw LED lighting, winch motors, etc.

Photo and schematic of Signal Power Mixer installed in my Hughes MD500 Tow Defender.

Redundant Battery Control Module

The Redundant Battery Control Module allows you to connect two battery backs to your flight electronics for an added level of safety and security while flying your prized aircraft. When using the Redundant Battery Control Module if one of your battery packs, on/off switches, or wiring has a failure like an open circuit, low voltage, or a complete short circuit, you will still be able to fly and land your aircraft safely without damage. You will always know the status of your system by the three status leds.

The Redundant Battery Control Module is constantly monitoring the voltage from each battery pack. If there is ever a voltage drop-out the last more than 5 micro seconds (that's five one millionths of a second) the Redundant Battery Control Module will detect this and start flashing the red led for that battery pack. It will also alarm you if your battery pack is getting to low for safe flying. The Redundant Battery Control Module also has a green heartbeat led to let you know it is alive and working fine.

The switching from one battery pack to another is instantaneously. There is never a time when your flight electronics is without power. The lowest voltage your receiver and servos will see is whatever the voltage is of your backup battery. For example, if your main battery is a 2S Lipo, and the backup battery is a 2S Life, if the main battery voltage fails the voltage to the receiver and servos will only drop from 7.6 volts to 6 volts. Never does it drop below your backup battery voltage. So you will have plenty of voltage to fly around with and land safely. It is recommended that you use the same battery type for both the main and backup, but as this example shows, you don't have to. It's totally up to you.

The system is designed to work with 2S Life (A123), or 2S Lipo.

The Dual Battery BackUp has the same diode options as it's older brother the Battery Voltage Mixer. This means you can tailor the system to meet your needs. If you want to force all power to be drawn from your main pack, and keep the second pack as a back-up only, you can do that. If you want to draw power from both battery packs evenly, you can do that also. You simply select the correct diode option.

Automated FLIR controller

The Automated FLIR controller module is used to simulate the FLIR operator scanning around to see the enemy targets. On the left side there is also an optional on/off pushbutton to stop the scanning motion. Operation is simple. Just plug it in like you would any servo, then plug the FLIR servo into it. The servo and the connector it plugs into is not shown in the photo.