I am restoring my Sansui AU 6600. On the f 2097 driver and power supply board there are four(two for each channel) 3W cement resistors rated at 0.47 ohm
I took all four out of the circuit and tested them and the meter reading is between 0.68 and 0.71 as you can see from a photo.
My question is, as I don't the tolerance looks like they are about 40% over the 0.47 listed in the part list.
Is that OK? Does that mean that after over 40 years the resistors have changed the resistance? Do I need to replace them?
Here is what they look like:
Hi thank you for your reply. I've red your reply, I must be honest but my knowledge is not sufficient to fully understand it. However just for curiosity attached a photo showing what happened to the resistor R47. Plus a photo of the schematic. This amp was in very bad shape (still is I am recapping it at the moment)as I got it from a friend who had it repaired several times over the years....anyway so the channel (if i remember well the left where the resistor R47 is ) is gone and the two power transistors (2sc898 and 2sa758) are blown out. Actually I didn't find those exact ones but instead there were motorola (genuine or counterfit??) Mj15025 and MJ15022 . Sorry I am new to this site I tried to give you 5 points but was allowed 2 only. Cheers