Hi All
I'm trying to restore a VZ-2000e but there's seems to be a problem with the power. Power LED was coming on but would then quickly go out again very soon after power was switched on. It had been not been used for well over 20 years so thought age had probably affected the caps and so I replaced the 5 caps on the board and power worked normally again for a while, although it was only being turned on now and again for testing because I'm trying to sort out a no sound problem in left woofer.
Looking around the power board I've noticed that where resistor R713 ( 4.7k Ohm) should be, there's actually a 10uf cap, and where there should be a cap reference C707, according to the printing on the board, there is a 4.7k Ohm resistor. The R713 resistor is listed in the parts list at the end of the service manual, and on the schematic, but I can't find any reference to cap C707 in the parts list or in the schematics. There is a an area of the power board schematic that is blacked out in the service manual and so it could maybe be hidden by that blacked out area.
It won't be the first time components have been fitted in the wrong place straight from the factory and this boombox definitely hasn't been opened since it was manufactured, until recently. I had it back in the early 80s and it had been played to hell and back for about 10 years with no problems with the mentioned components having been in place from the factory. I found a restoration thread here on Boomboxery from Dbzerk, who restored a black cone model in 2018, from which I can see the resistor and cap appear to be where I'd expect them to be based on the printed references on my board. Not sure exactly what model the black cone model is but I know model components vary slightly. Mine is the red cone one.
I've included an image of the black cone board and arrowed the resistor placing, and one for the red cone model (this is another I found online by the way just to show it's not just mine that has a cap where the board says the resistor R713 should be).
In any case, I suppose the question I'm trying to ask is should I switch the components to match the board references? That's easy to do for the resistor but I can't find any reference to cap C707 in the service manual and don't really want to guess at anything, so if anyone has a VZ-2000e red cone open for restoration, could you shed some light on what components are in the R713 and C707 references on your board. Thanks
I'm trying to restore a VZ-2000e but there's seems to be a problem with the power. Power LED was coming on but would then quickly go out again very soon after power was switched on. It had been not been used for well over 20 years so thought age had probably affected the caps and so I replaced the 5 caps on the board and power worked normally again for a while, although it was only being turned on now and again for testing because I'm trying to sort out a no sound problem in left woofer.
Looking around the power board I've noticed that where resistor R713 ( 4.7k Ohm) should be, there's actually a 10uf cap, and where there should be a cap reference C707, according to the printing on the board, there is a 4.7k Ohm resistor. The R713 resistor is listed in the parts list at the end of the service manual, and on the schematic, but I can't find any reference to cap C707 in the parts list or in the schematics. There is a an area of the power board schematic that is blacked out in the service manual and so it could maybe be hidden by that blacked out area.
It won't be the first time components have been fitted in the wrong place straight from the factory and this boombox definitely hasn't been opened since it was manufactured, until recently. I had it back in the early 80s and it had been played to hell and back for about 10 years with no problems with the mentioned components having been in place from the factory. I found a restoration thread here on Boomboxery from Dbzerk, who restored a black cone model in 2018, from which I can see the resistor and cap appear to be where I'd expect them to be based on the printed references on my board. Not sure exactly what model the black cone model is but I know model components vary slightly. Mine is the red cone one.
I've included an image of the black cone board and arrowed the resistor placing, and one for the red cone model (this is another I found online by the way just to show it's not just mine that has a cap where the board says the resistor R713 should be).
In any case, I suppose the question I'm trying to ask is should I switch the components to match the board references? That's easy to do for the resistor but I can't find any reference to cap C707 in the service manual and don't really want to guess at anything, so if anyone has a VZ-2000e red cone open for restoration, could you shed some light on what components are in the R713 and C707 references on your board. Thanks
