Re: Another Advance E2 Signal Generator.
I have just received the E2 and on opening it I see that it has been modified.
The transformer has either been modified or replaced. There is a label on it giving the connections for linking for 105 to 125 or 205 to 250 as per the schematic but someone has hand written on it 0, 230, 250. The mains is connected to 0 and 230
Additionally there is a secondary missing. according to the schematic the rectifier valve should have its own winding for the heater but instead the heater is in parallel with the other heaters with one end grounded.
The main electrolytics have been replaced by an RS dual capacitor and much increased in value, the first cap after the rectifier has been increased from 16 to 64u and the second capaciytor has increased from 16 to 100u
The series resistors have also been changed, the one from the rectifier cathode to the first capacitor has been REDUCED from 560 to 22 ohms and the resistor to the next cap has increased from 1K to 2K (2 X 1K in series).
Would these mods be considered safe, especially the increased capacitance for the rectifier?
According to the valve museum, "In normal use the maximum reservoir capacitor is limited to 4 µF and the minimum series resistance has to be 150 Ohms."
Peter
Last edited by Electronpusher0; 5th Jun 2019 at 5:27 pm.
Reason: added valve data
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