Good tutorial! I'm not quite confident enough to touch my own circuit boards with a soldering iron yet. But I'm going to do 2 things: 1) I've bought a Heathkit clock kit to get some practice, and 2) my Sansui 661 blew the fuse for the lamps when I tried to install LED lamps, and it's an axial fuse soldered in. (Working in automotive the idea of a fuse soldered in is quite strange.) I've ordered replacement fuses and will give that a shot.
The original fuse-style incandescent lamps are probably rated for 8 volts; the receiver's power supply voltage to illuminate them is probably 8 volts AC (not DC), or a little less under load (the incandescent lamps draw a lot of current), but because LED's draw so little current, the 8 volt supply for the original lamps might rise to 10 or 11 volts, and might require a dropping resistor to lower the voltage to tge LED's. The LEDS will need a builtin rectifier to convert the AC supply to DC ( some led lamps have this, some don't). Hope this info is helpful. Changing a vintage receiver over to LEDs is rarely a straightforward "drop-in" procedure!
Thanks for tips about working on the *easy to damage* phonetic boards. Very different technique than the modern fiberglass boards.
Hi Bryan, camera is much better
Good tutorial! I'm not quite confident enough to touch my own circuit boards with a soldering iron yet. But I'm going to do 2 things: 1) I've bought a Heathkit clock kit to get some practice, and 2) my Sansui 661 blew the fuse for the lamps when I tried to install LED lamps, and it's an axial fuse soldered in. (Working in automotive the idea of a fuse soldered in is quite strange.) I've ordered replacement fuses and will give that a shot.
The original fuse-style incandescent lamps are probably rated for 8 volts; the receiver's power supply voltage to illuminate them is probably 8 volts AC (not DC), or a little less under load (the incandescent lamps draw a lot of current), but because LED's draw so little current, the 8 volt supply for the original lamps might rise to 10 or 11 volts, and might require a dropping resistor to lower the voltage to tge LED's. The LEDS will need a builtin rectifier to convert the AC supply to DC ( some led lamps have this, some don't). Hope this info is helpful. Changing a vintage receiver over to LEDs is rarely a straightforward "drop-in" procedure!
your contrast is too high, try adjusting it in post, that way well see your shadow work.
Thanks, just getting used to this camera.