Greenbrook DAT01A Bell/Chime Transformer 4/8/12V

I have a house with a front door and an office 50 metres from the house. I simply wanted a doorbell in both so I could receive my Amazon deliveries.I tried two wireless options but neither worked, as despite having stated ranges of 100m and 300m neither reached more than about 20 metres through a single skin wall. So in the end I purchased a good old fashioned wired system and turned a length of network cable that was already running between the house and office into bell wire.** The Transformer**This is a simple mains transformer, you connect your live and neutral wires (no earth as it is double insulated) to the screw terminals on the input side of the transformer and it outputs 4 volts, 8 volts and 12 volts on the other side of the transformer. You select the voltage you want by connecting your 2 output wires to different combinations of the three output terminals, it really is very simple.This is an AC - AC transformer so there is no rectification to DC or regulation of the output voltage. Because of this, if you connect a multi-meter to the output terminals when there is little or no load the voltage will read much higher than rated, this is normal and exactly how it is supposed to function, as the power consumption increases the voltage will reduce to rated levels.There are mounting holes on the back to fix this to the wall and the cables can be routed through small cut-outs at the back. Cables can also be connected from the top and bottom after using a knife to remove the moulded recesses.When I first connected this it made a loud hum, however after 5 minutes this had reduced to almost imperceptible levels and is now silent, unless you put your ear right next to the unit.I am using the 8 volts output from this transformer and it happily operates this buzzer Byron 7201 Wired Wall Mounted Striker Buzzer Door Chime 50 metres away and this chime Byron 772 Wired Wall Mounted Door Chime 10 metres away as well as an illuminated bell push Friedland D534W 'Lightspot' Wired Illuminated Bell Push - WhiteOverall the system works excellently, there is no reduction in volume in either the buzzer or chime from running both in parallel and I haven't missed a delivery yet (although I am getting fit sprinting to the front door every time it sounds).

Fast delivery. Replaced old transformer. Works well.

I bought this after my existing transformer was making too much of a buzzing noise. After installing the unit it is very quiet, you can hear a buzzing sound but only if you put your ear close to the unit. Pleased with the performance of this item.First one I got was faulty and was replaced quickly. I found out that to test if it is faulty or not you just need a multimeter. Set it to ohms (resistance) and then connect to both the primary and secondary connections separately which if it's good will give you a reading. See this youtube video which helped although I think it refers to the USA system it but the same concept applies.http://www.youtube.com/watch?v=rktEpWJAI1k

Good product fast service

I was feed up replacing batteries due to the fact I had two bell and a long cable run so I decided it was time to purchase a transformer. It did the job but I have the following observation. The mains cable to the transformer does not have a sadel to secure cable only the terminals terminating the wires secure the cable. As a result you could pull the mains cable out by the roots. Additionally the screw that secured the transformer cover or case uses a self tapping screw into the mains terminal chocolate strip fixing hole. Ok to use if it is out of the way and would not be disturbed but I would have reservations if it was where it might be get disturbed. I will replace in time with something with a approval mark I recognise

Neat compact box, easy to install and working as expected with Ring doorbell

This is a very good and cheap door bell transformer (providing the power only). You need a basic understanding of wiring to install this device.For the voltage input side you will also need a 1amp fused plug and and cable to plug into the mains socket or you can wire it into a 1amp fuse spur.I am using this to connect a 8v/12v AC buzzer/bell to a RING doorbell. RING will not charge effectively on 4v AC.

Update: replaced with a BT4812 transformer from Eterna, same spec, better build quality and no noise whatsoever.Worked to power a Logitech Circle View Doorbell I imported from the US, no issues with the functionality itself.But, it emits a very annoying buzzing sound that permeates from under the stairs into the whole hallway, so I'll have it replaced with another product at some point. The case is made from cheap plastic that was warped, wouldn't even sit flush on a table. The transformer itself looks handmade, with really rough soldering and loose connectors.I guess it works, the plastic and build quality don't bother me too much, but the buzzing noise is a constant reminder I need to get a better product.