While at the back of the house, where I need the extra wireless range, due to run down batteries in the Friedland Libra+ D917 door chime I recently missed parcel deliveries, which then had to be collected. Hopefully this power adapter will prevent such problems in future.
Without the weight of the batteries, the chime is more easily knocked over if standing on its end.
As with most Friedland products, it is quite expensive for what it is, but there is no concern about it working properly. It will take a long time to pay for itself, but will provide peace of mind.
You can get a "Universal Regulated 600mA AC/DC Power Adaptor" with 6V output for just £6, including delivery (well under half the cost), that should do the job just as well, but care would be needed to ensure the correct plug size, polarity and voltage, so this Friedland adapter avoids that complication.
It looks somewhat different to the picture shown and projects upward from the socket, which can be a problem if the socket is close under a shelf. Because of its different shape I was concerned it might not be a genuine Friedland product, but a check of their latest online catalogue shows this is the current design.
It comes with a generous 2m long lead, to allow plenty of scope for positioning the chime relative to the socket.
Note that the Friedland D917, et al, do not have a 300m range, as quoted, but a claimed maximum range of 200m, and then only in open space.