raversnature

is there any lights on the MPU. 1 RED LED on MPU-4's and 4-5 LEDs on MPU-5's double check the 12v and 24v fuses and their carriers it's not uncommon to have a duff fuse carrier on the LDV supplies. also ensure the carrier seats firmly and securely in its holder.

ensure the power connector from PSU is firmly connected to MPU
a small buzzing sound is quite normal for these supplies when they are under load. if it is very load though, you may well have a short-circuit within the supply and a replacement will be needed. you could go to a local amusement machine supplier and they may sell you one from a scrapped machine or direct you to someware you can lay your hands on one. hope this helps.

the solonoid is the big black lump attached to the bottom of the coin tube (20p tube in your case.) although sometimes orange in colour check for obstructions in the very bottom of tube ( wrong coin for instance ) also check to ensure that the wires are attached. (normally pus-on spade connectors.) WARNING.!!! Whilst the solonoid is only between 24-50v when energized it can give a VERY PAINFUL shock. so ensure that you are not touching it while testing and if you need to connect/disconnect wires from this unit then power down the machine first. I learnt the hard way.!!!! did'nt do it again.!!

is the machine running MPU-4 or MPU-5 ( looks like MPU-4 (poor vid))
is the machine " eating " ALL coins or is it only swallowing particular coins
is there any other faults with machine alarming etc
if alarming post alarm code number displayed this will tell me how to rectify any possible connected problems
post this info and i will post a step by step guide on what to look for and how to possibly fix the problem yourself.
Your coin acceptor is a MARS ( MEI ) 126 DF (X) these are known to loose their coin windows. but this can be fixed as these mechs are re- " teachable " without to much trouble.

the flash memory is a 128MB CF card that contains the machines game software running on 2 HEBER video controllers some versions operated on PLUTO 6 MPU's

Hi. this may or may not be helpful as regards emulating s16 machines.
i work as an area technician in the uk maintaining and programming these and other high tech amusement and casino equipment.
Astra games ( Novamatic group of companies ) make Party games Slotto/ Little devils slotto Reel King and others. Astra uses the I.O.3 integrated MPU connected to a fairly standard PC in a custom case. it uses Windows XP-Embedded as the operating system with 1GB of DDR mem and 40GB HDD of which only about 20GB is used. comms is by means of standard serial for the game and CCTALK for the acceptors. security of the software is by means of the F.P.G.A. chip mounted on the I.O.3 MPU. which protects the ACP Roms on the MPU. the R.N.G. unit would be quite easy to emulate as it is not protected by any form of security as far as im aware.

Barcrest S16 units:- Elvis,Elvis top20,Rainbow Riches,Lucky Strike. and others mounted in the advanced Rio cabinets under the MPU-5.
These work as follows:- the PC is again fairly standard, O.S. is Windows XP-Embedded ( XPE ) 40GB HDD,1GB DDR Mem comms is by means of USB to Serial from the R.N.G. USB to the touchscreen and Serial SPi for the note and coin acceptors the PC does not have any direct security as such but has a flash programmed MPU-5 program card which is secured pretty good. there is usb comms between this which controls crediting, meters and other auditing functions. the R.N.G. unit is also quite a simple affair which delivers a random number to the machine when request signal is sent to it. Hope this helps, to explain fully how the operation of the units work is beyond the space that would be allowed for replies on this forum. I have a full Backup of Elvis if someone could tell me how to upload it ( Ghost image 2.5GB ). Good forum keep up the good work.!!!!