Hi John 13.55MHz rings a bell for the ISM frequency, which is the US "HiFer" allocation as well. Most of the kit I have seen (not a lot) in the last 20 years had crystal control, but the supply is no
Hi Peter, the immediate thought is DSL ( or ADSL) or even ISDN lines. I would not lay too much store by BT "engineers" not being able to find it. These guys have little or no RF experience in genera