If like me you are not getting MLAT to sync up or other messages such as clock unstable or CPU running out of cycles. Then check your coordinates actually match your location on the Skyaware map. I noticed that my displayed location was actually way off from where I lived. I used a Postcode to Coordinate converter and manually updated my location on my piaware stats page. MLAT is now sync’ed to 171 nearby receivers. Problem fixed!
Agree using a tool to find exact coordinates is best practice, but as the OP is in the UK the post code converter he used can provide a pretty close result, better than many would think. When I lived in the UK I was shocked at the granularity provided by the UK post code system. A handful of houses on a single street is a post code. For fun I punched in the three post codes where I used to live into one of these converters. The results were between 5 and 30 meters off from my former residence. Not bad.
UK postcodes are surprisingly good in urban areas - each covers no more than 100 addresses (and more usually 10-20), so +/- 50m is reasonable. It’s very common to provide your address (to businesses etc) as postcode + street number.
(Singapore’s postcode system goes even further - each building has a unique postcode)
Yes, the UK is the only place I have been where this approach would seem to work relatively well. I took a closer look at my last two addresses in the UK. One was in a town (circa 75,000 population) and my 450 meter long road has three different postcodes assigned. I also lived in a rural village of 1200 souls on a private gravel road which degenerated into a farm track at end of which was my house. My landlord lived 75 meters a way in another house. We had different postcodes!
We have this also in a few large cities (Berlin, Munich etc.) where single streets or even a single building can have it’s own postcode. But most of these are larger companies where the block is not counted as single building.