How to replace proms on the SDS-7 module board
This text is taken from the SDS EP8 manual (sampler and eprom blower)

Ensure that the SDS7 is switched off and the mains cable is disconnected.

a.	Loosen and remove the four fingertight, knurled screws fastening the front panel to the rack. Remove the front panel. There is no necessity to remove the two knobs on the front of each module as they protrude through the front panle from behind.

b.	Remove the relevant module by grasping the top and bottom of the circuit board between thumb and forefinger and easing slowly forwards. The module will slide out on its guide.

c.	The prom which generates the digitally stored sound is located in a plug-in mounting at the bottom left corner of the board. Ease this components out of its socket by use of the IC extractor provided. Ensure that the fingers of the extractor mate correctly with the legs of the prom and pull perpendicular to the circuit board.

d.	Replace the new prom. First ensure that the legs line up with the locating holes in the socket and that the prom is the right way up. (Refer to the diagram showing the notch). Locate the legs into the socket, press firmly home with the thumb.
	NB. If a leg is not lined up correctly it will bend and the prom will not function.

e.	Replace the module by sliding it into the card guide and when it reaches the back of the rack, ease gently up and down until the groove on the circuit board mates with the key in the socket, ensuring that the correct connection are made. It is advisable to check first that the tiny black key is correctly in place in the locating socket at the back of the rack. If you are in any doubt, consult your dealer.

f.	Repeat this action until all the desired proms are replaced
	NB. It is important that bass prom go only in bass modules, toms in toms etc. replace the front panel and tighten the securing bolts with your fingers.

g.	To output the ‘straight’ sound of the prom when the drum pad is struck, analog level and digital modulation controls should be set at 0 and the digital level at 255. The digital pitch should be set around 130 as should the bend control. The filter should be kept open for the duration of the sound to allow the full bandwidth of the sample to be outputted. However, the limitation of sampling gives rise to certain amount of noise during and immediately after the sample has ended. It is therefore suggested that the decay control is utilized to vind back to the end of the sample closing off the noise. If analog tone and noise generation are being used to complement the sound, their level will be more than sufficient to mask the noise following the digital sample.