It's an affordable option, but read the Practical Motorhome Labgear DVB-T Finder review to find out more about this product
The Labgear is the cheapest unit we tested. The instructions are short with a clear diagram. It has four LED lights and while reading the signal is simple, it isn’t well defined. The unit struggled to find the strongest signal and we had to be patient before it reached two lights and we had a decent TV picture. It comes with adaptors but not a battery, and fitting one was awkward.