03-12-2013, 08:44 PM
(03-12-2013, 07:59 PM)standunmj Wrote: hi joe and guys, the schematic that colin kindly sent me , gives.... il6. iu4, iu4, iu5. 3v4, my set is fitted with dk96 ,df 86, df86,daf91, and a brimar [unknown] four of the d type are mullard ,the numbering is anything but clear , so the plot thickens, any suggestions chaps ?maitiu.
The 96 series are 25ma heater current, the 91 is 50ma heater current, if they are all still connected in series then the heater shunt values need to be adjusted to compensate, don't forget that the shunts will also shunt the anode/screen currents.
Personally I would investigate all the heater shunt resistors to see if they are the original specified values or if they have been changed at some time for different values, then take it from there. Let the forum know if they are the original values as specified in the schematic.
Lawrence
