On the signal test thing on my iPhone, when I use a leading * I get a “your request was not recognized” message. When I use a leading # I get a “Error performing request, Unknown error” message.
Sounds like you missed the pound sign at the end of the string.
It was the final asterisk I was missing. Thanks.
Now I know that the signal strength around my house varies between -98 dbm and -125 dbm. Mostly worse than -198.
That’s what I get for living in the country.