There it is. The Jack Crossfire version of the Maxbotix amplifier. No matter how much money your boss makes by copying reference designs, we hate copying reference designs. So after several hours of trying components, made a slightly simpler version of the Maxbotix amplifier. It isn't as stable as the Maxbotix, but it has longer range & you can fix the output in software.

Using Fry's ripoff parts, this circuit + the transducer cost 1/2 as much as buying a full Maxbotix for reception. If you want the full measuring device, you're better off paying full price.

This circuit is extremely powerful. Indoors, it senses the transmitter from 10ft away, mostly omnidirectionally. It can sense the transmitter 20ft away if they're pointed at each other or there is a reflection. The trick with indoor operation is reflections from indoor objects. It won't do as well outdoors. It's sensitive to ambient noise, clapping, & probably aircraft.

Since we caved in & threw in tons of op-amps, we might as well run the transmitter off a 20V op-amp & see how far that reaches. You can also try putting a diffuser under the transmitter. That would require losing altitude sensing by reflection & building 3 of those reference designs, so forget about it until the system actually flies on 5V.

Hello!

We just noticed this post and would like a chance to comment on this. We think this should be the case, since we should at least have an ability to respond to comments about us as a company or our products.

You mention about your circuit that, "it isn't as stable as the Maxbotix, but it has longer range & you can fix the output in software... This circuit is extremely powerful..."

Our LV-MaxSonar-EZ1 ultrasonic sensor can detect walls to 21 feet, (this is a longer range than what you claim), so we are not sure what you mean. Also, our XL line of sensors output way more power and have noise immunity.

The electronics in all of our products is stable. For example, measurement stability (standard deviation) for a MaxBotix ultrasonic sensor to a stable target, in stable air, (all of our sensors) is 0.5. What this means is that our product's stability is 1/2 of the sensor reporting resolution. So for LV this is 0.5-inch, and for the XL this is 0.5-cm. In addition the toggle from one increment to the next occurs over about a 0.01-inch (0.25-mm) window. (Wow, as far we know, this is the most stable in the low-cost ultrasonic sensor industry.)

My two cents,
Nicole Smith
With MaxBotix Inc. Marketing & Sales Support