Noise Suppressor Kit for SCR522 Boxed, kit of 2 units and tube, wired etc. Think it needs 1 more 47K resistor. £10. http://www.vintage-radio.net/forum/attachment.php?attachmentid=79617&d=1368200978 http://www.vintage-radio.net/forum/attachment.php?attachmentid=79618&d=1368200978