Replacing Axial Caps with Radial Caps
Many of the WOS members have complained of how difficult is it to get hold of Axial Capacitors when they want to replace the electrolytic capacitors on a ZX Spectrum. I wanted to see how easy it would be to replace the caps with radial caps without having long ?antenna? wires, which you will have to insulate to minimise the possibility of shorts on the board. In practise they also sometimes start acting as antennas especially if there are high frequencies around. ALL the caps except C65 must be mounted flat onto the board or else the case will not close.
At the end it was quite easy and I took a few pictures to show the configurations per cap. I just looked for existing pads on the board in the close proximity of the original caps in which the legs of the caps can be soldered into. The newly used pads are all directly connected to the original pads with either tracks on the bottom or top of the PC board. This is probably old news for the seasoned repair members, but it will maybe assist some newcomers. I have done the demo with an Issue 2 board, but the same principle can be used with the other Issue boards.
C25 : The negative side in the original pad and the positive in the adjacent pad.
C27 : Use the two pads to the left of the original positive point on the board.
C28 : Use the two pads at the bottom of the C28
C34 : The positive side in the original pad and the negative soldered on the track next to c41
C44 : The positive side to the right of the original pad and the negative on the pad to the top of positive pad.
C45 : The positive side in the original pad and the negative soldered in the pad on the bottom the positive pad.
C46 : The positive side in the original pad and the negative soldered in the pad to the left as in picture.
C47 : The negative side in the original pad and the positive in the first pad to the top of the negative.
C50 : : The positive side in the original pad and the negative soldered on the track next to R58
C65 : Into the original holes. Keep the wires as short as possible and take care not to short any tracks.
Good luck and have fun
Pierre
At the end it was quite easy and I took a few pictures to show the configurations per cap. I just looked for existing pads on the board in the close proximity of the original caps in which the legs of the caps can be soldered into. The newly used pads are all directly connected to the original pads with either tracks on the bottom or top of the PC board. This is probably old news for the seasoned repair members, but it will maybe assist some newcomers. I have done the demo with an Issue 2 board, but the same principle can be used with the other Issue boards.
C25 : The negative side in the original pad and the positive in the adjacent pad.
C27 : Use the two pads to the left of the original positive point on the board.
C28 : Use the two pads at the bottom of the C28
C34 : The positive side in the original pad and the negative soldered on the track next to c41
C44 : The positive side to the right of the original pad and the negative on the pad to the top of positive pad.
C45 : The positive side in the original pad and the negative soldered in the pad on the bottom the positive pad.
C46 : The positive side in the original pad and the negative soldered in the pad to the left as in picture.
C47 : The negative side in the original pad and the positive in the first pad to the top of the negative.
C50 : : The positive side in the original pad and the negative soldered on the track next to R58
C65 : Into the original holes. Keep the wires as short as possible and take care not to short any tracks.
Good luck and have fun
Pierre
Post edited by Pierre on
Comments
/Pedro
Yes, I also normally purchase axial caps and have mentioned that somewhere in one of the forums as well, but I had some problems acquiring 22uF axial caps last week and so I just wanted to see what the best options available was. I deliberately only used radial caps with this Spectrum just to show it is quite easy. I also have used the option of bending one of the wires back, but then I normally put some isolation over the exposed wire.
/Pedro