Changes for Version 2 --- July 2020
We are changing the packaging for the Heat Guardian units substantially. We are switching from the matched pair of Heat Guardians (version 1) to a base/mobile pairing (version 2).
The hardware board inside has gone from version 7 to Version 8.
Version 2 - base and mobile with version 8 hardware
Version 1 - matched pair with version 7 hardware
What's Not New
Same electronics inside
The V8 and V7 internally are almost exactly the same. The LED lights, the speaker, the microcomputer and two radios are the same in both units. The V7 and V8 units can talk to each other and can be mixed-and-matched if desired. They run the same firmware.
One Mobile and One Base Unit
We are switching from two identical mobile units to one mobile unit and one base unit. There are two main reasons we did this.
Simplicity - there were many questions of the "Which unit goes in the vehicle?" kind. This makes that much more obvious.
Stability - we expected folks to hang the vehicle unit from a hook in a window. Instead, most folks just wanted to set it upright on a crate and any door slam or wind would knock the unit over - ruining reception. The new base unit is much more stable.
The base unit has no display but it does have a long range antenna and the ability to switch to other antennas, such as roof-mounted antennas for extreme range in an RV.
A directional roof-mounted beam antenna. This foot-long antenna sends 2x-4x the distance of a standard long range antenna
The base unit is very stable in wind, so it can be securely set on top of a pet crate or table.
Faster Temperature Response
The V7 temperature sensor is incredibly precise, but physically large (it's the size of a jelly-bean) and so if your temperature changes quickly (like the air conditioning goes out), it may take a few minutes to fully react. The V8 base unit has a smaller temperature sensor (the size of a bead) so it reacts more quickly.
The new box has more air holes, to help with air circulation, to again react more quickly to temperature changes.
Both the V7 and the V8 sensors are incredibly accurate. The V8 sensor does use a tiny bit more power than the V7 sensor.
The graph on the right shows the two sensors responding to removing the unit from a refrigerator at 40°F. Both units end up at the same temperature, but initially the V8 responds more quickly.
The V7 unit uses rechargeable batteries that are AAA size. These work well but the tubular shape is inefficient and the usual AAA battery connectors may, over years, corrode - just like standard AAA battery holders.
The V8 unit uses rechargable batteries that are rectangular and not as deep. This lets us put them into a smaller box and the connector should be more reliable over the many years you own the unit.
We have tuned the unit firmware so V8 lasts as long as V7, even with a slightly smaller battery. Also, because the base unit has no display, it uses very little power and even with the slightly smaller V8 batteries it easily lasts 3 days.