26-08-2014, 06:16 PM
Thanks for your replies, regards the RSGB reference I made, there isn't a circuit, or if there is I haven't seen one either but there is this paragraph on page 6.3 of the 5th edition of the Radio Communication Handbook 1991 which mentions the bulb or TC meter, I've also attached a page from the J Douglas Fortune book where he says that the bulb is used to provide a guide to the current.
John
John
