• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Modify Jolida 202A to power amp

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Fortunately, this 1 is easy. Look at the schematic. The Jolida 202A is a Mullard circuit power amplifier, with source selection and a volume control at the I/P.

Connect the AUX I/P jacks to the wipers of the volume controls, instead of the source selector switch.

BTW, a very simple modification will improve PSU performance. Replace the 4X 1N5408 diodes with totally compatible UF5408s. The amount of SS diode switching noise will be greatly reduced.
 

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Eli,

Last time I tried working on this amp it wound up in the shop needing a transformer. Yes I am wanna be diyaudio enthusiast. I will need to study the schematic and perhaps seek some local expertise before tackling.

BTW I have had this amp since early 1995. If memory serves Jolida was entering the US market and was practically giving these away. Never regretted this purchase.

Thanks for the simple solution, schematic, and Pro tip on diode upgrade. May I ask what you meant by totally compatible? Looked Mouser.com and it seems for less than $5 I can reduce the switching noise. Amazing. I will open the hood and check to see which diodes are in my unit.

Again appreciate your help very much.
 
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