This mod will remove the trimmers from the issue two ZX spectrum, potentially getting more life out of ULAs that won't tune easily, but ultimately removing the need to open the case to adjust the picture.

As featured on Happy Little Diodes youtube channel.

Design work by Peter Mulholland

Installation Steps

1. Remove R38, R39, R40, R41, R56, R63, C52, C53, VR1, VR2
2. Fit 470 Ohm resistor between right terminal of the footprint where R41 was and +5 V, use a +5 V which is connected directly to the output of the 5 V voltage regulator. One can be found 1-2cm below the left hand keyboard connector. Use heatshrink to insulate the resistor legs.
3. Connect UV mod board to the spectrum PCB using 2x1, 2.54mm pitch header pins to the right terminals of the footprints of the removed components as marked on the mod board silk screen. Orientation as shown in the pictures on this project page.
4. Use fly leads to connect +5 V, Y and Ground as marked on the UV mod board silk screen
5. +5 V and Y can be found in between TC2 and the ULA , note that Y is accessed using a small via and you should scrape some solder mask off the underside of the joint for a good connection, an alternative is the Y link to the left - you can also get +5 V from the bottom leg of the large resistor here.
6. GND can be found on the left terminal of the footprint where C33 would be if it were fitted.