Leaderboard

just done some working out, with the resistor 27 ohms and the speaker at 30 ohms this totals 57 ohms, the supply is 12v so when the transistor T11 turns on 210ma passes through the transistor collector to emitter, that's 2.53watts, the transistor is rated for 800ma. but if the 30 ohm speaker is replaced with 8 ohm this becomes 27ohm resistor +8 ohms = 35 ohms, so the current goes up to 343ma and 4.12 watts! its still well within the transistors switching capacity, but as its most likely 40 year old transistor it will most likely die as these are prone to failing with age even when everything is all correct! also the increased current and switching the transistor on and off rapidly to create the 'tone' will cause heat in the transistor junction which can also cause the transistor to fail, but may be fine for a while. so its up to you really what you do. Others will say just change the speaker from 30 ohms to 8 ohms, and yes it will work, but it is entirely up to you if you want to do that, or do it properly. I would presume 30 ohms was chosen so a 3w 27 ohm resistor would be well within the ratings, with the 8 ohm speaker 4.12w puts the 27 ohm resistor as well under rated at just 3w

I have got one of these, im still trying to suss out all the features, but its a nice game to play.. im amazed at how you make these emulators i may challenge you to making one for my jive money coin pusher. this is a pic of viva Las Vegas. so you can see the layout.

That's fantastic mate .thanks ever so much for the advice and very much appreciated 👍👍👍👍

That's brilliant, thanks so much for that.👍