Page 1 of 1

jetpac arg the pain

PostPosted: Sun Mar 22, 2015 10:56 pm
by mangasurfer
My cousin and i setup both our spectrums together in the same room on separate tvs loaded jetpac on each. And then started a race to see who could clock the game first. not sure who won. Will let justin be the winner. Think we then just kept going for hours till we both got head aches. Then i think the next day i was seeing what would happen if i touch the edge connector with some wires. It did produce some interesting pictures before costing my parents about 400 to get the spectrum repair. Managed to get it updated to 48k as well. Lol my son whos ten played jetpac for about 5 minutes. Was not impressed

Re: jetpac arg the pain

PostPosted: Mon Mar 23, 2015 9:51 am
by tezza
LOL. Thanks for the memories!

Re: jetpac arg the pain

PostPosted: Mon Mar 23, 2015 12:34 pm
by RonTurner
Yes joining the connections with a wire is known as a "short-out". Shorts are very destructive as you have learned.

You should also know there are voltages at the edge connector like 12volt that will destroy chips.

Dont plug ZX81 interfaces into spectrums or vice-versa i bought a interface II from trademe guy told me he had been trying spectrum interface in zx81 and showed it working on trademe, he delivered it to my place,went inside, had spectrum setup, plugged it in and DEAD !The guy had shagged it in his zx81 but i guess he really needed the money becuase he keep it quite, i was afraid of getting negative feedback so i left it alone. He then sold some other dead items admitting on one auction he had shagged it plugging it into a zx81,

Check with uncle google first next time and find out what happens before you experiment.

Re: jetpac arg the pain

PostPosted: Wed Mar 25, 2015 10:21 pm
by mangasurfer
Yes ron. I know your pain of buying old computer stuff that was ment to go i brought 7 arcade pcb off trademe back when you could do wanted ads. Boards turned up not a single goer. Damn i was mad. But i manged to repair most of them learnt a lot about cpu data buses and the joy of owning a logic probe. Was great fun.

Re: jetpac arg the pain

PostPosted: Tue Sep 27, 2016 10:10 pm
by mons2b
Skills repairing the boards Manga!

I know I could use uncle google. but more fun to ask you.. whats a logic probe? :)

Re: jetpac arg the pain

PostPosted: Fri Oct 21, 2016 6:12 am
by mangasurfer
Whats a logic probe. indeed its for probing lol pins off chips on a curcuit board. example a heavybarrel game i had would just lock up. so got the cpu pinout hooked the power on and started by touching the clock pin on the cpu. the logic probe started beeping if its 0 volt no beep if +3-5v beep. so fast beeping clock ok. if nothink happened i would have to assume no clock or power to clock curcuit etc. any way then i check all the data lines all where beeping sweet as. next stop the ram all good. so then to the roms found 2 roms had data lines that where not beeping so add a patch wire. checked again all beeping. stuck it back in machine. 20 minutes later game clocked lol.

mons2b if you want someboard probed just email me and we can have a look and can show you how to get the logic madness. may be i will do a video and post that if you interested