[m0cemdave]

You will find the biggest problem on the shortwave broadcast bands is the large number of "ethernet over mains" systems now in common domestic use.
Although many of them are designed to avoid wiping out the amateur bands, nobody ever lobbied the manufacturers to protect the broadcast bands.
They sound a bit like a troop of horses clattering over cobblestones, and completely wipe out reception.

There is also a high level of what sounds like white noise which is caused by badly balanced overhead telephone lines carrying VDSL internet. This won't stop until the UK catches up with the developing world and replaces copper landlines with FTTP.

And of course all the switch mode power supplies in use in your and your neighbours' homes. Wall warts, phone chargers, general domestic electronic equipment - all made as cheaply as possible in China and much of it with no RF noise suppression. Not to mention plasma screens!

The result of the above, (unless you live in an isolated house a couple of hundred yards from anyone else) is that you need a carefully designed aerial that maximises wanted signals over general noise pickup. So at the same time as building your radio, build a loop antenna (plenty of designs on the internet) and find somewhere to install it away from all the garbage. If you don't do so, you will be very disappointed...