Good video Tommy, it's nice to know that I'm not the only person to fix one thing and thn have something else fail. It's just the nature of these wonderful old machines. Keep up the great work and Happy 2024!
I just grabbed my can of silicone spray and I am just waiting for the chance to spray one of these keys... In fact I never would have thought of that solution and probably would have reached for the dremel and done something destructive. Great videos as always.
hi tommy.. you did a good job! but like you said at the end the power draw was too much....i will be glad to see part 2 when you fix it. also i love that harlequin spectrum! it is a beautiful machine !! snd u like all your goteks e t!!!lets try to have the best year in while....😊
The little square of wire links underneath the heatsink on the issue 2 board selects between NEC and Hitachi pinout ROMs. That might be the reason why some ROMs work and others don't.
Hi! Nice video! I had a similar problem connecting a defective dandanator, i got fried TR4/TR5 (They are responsible for giving the -5v and +12) and lower ram in two zx spectrum! Thank goodness I realized it was a Dandanator thing, otherwise I'll end up burning my entire spectrum collection 😅
The links for setting the ROM are most likely soldered then the ROM was swapped. The links are either H or N, H for Hitachi ROM and N for an NEC brand ROM, it looks like the links were cut and then rotated 90 degrees to the other position. They have different select lines but both have 2 lines. A 27128 has only 1 select line. The two original select lines need to be combined with an "OR" and that is what the 2 diode modification does. That one EPROM works is maybe because one of the pins is floating. While it may work now, if an input is floating it can crash anytime. I would not use it without the modification. Your original ROM might be perfectly fine too, depend on if the chip tester knows how to enable it. And since there are 2 different ROM versions using a different method, maybe the tester is using the wrong one. When you so the EPROM mod then also the original ROM works, regardless of the type.
Some days you get the bear, and some days the bear gets you. You were lucky: there was a little of both today. From your video remarks, it looks like you may have found the issue, so do please follow up on this one.
Good video Tommy, it's nice to know that I'm not the only person to fix one thing and thn have something else fail. It's just the nature of these wonderful old machines. Keep up the great work and Happy 2024!
Thanks 👍 Happy 24 :)
Another great video. Loving the soundtrack as well!
Glad you enjoy it!
I just grabbed my can of silicone spray and I am just waiting for the chance to spray one of these keys... In fact I never would have thought of that solution and probably would have reached for the dremel and done something destructive. Great videos as always.
Thank you :)
Such a cool diagnostic cartage Tommy, it a shame the machine pooped itself again. I'm confident a man with your skillset will get it sorted.
Thanks, I will fix it some day :)
Looks fun! I have no experience with the ZX Spectrum+. Let us know it goes with the diagnostics. :)
hi tommy.. you did a good job! but like you said at the end the power draw was too much....i will be glad to see part 2 when you fix it. also i love that harlequin spectrum! it is a beautiful machine !! snd u like all your goteks e t!!!lets try to have the best year in while....😊
Ok thanks!
The little square of wire links underneath the heatsink on the issue 2 board selects between NEC and Hitachi pinout ROMs. That might be the reason why some ROMs work and others don't.
Aha, I did not know. Thanks!
Hi Tommy, best wishes for 2024 for you and your family. Greetings from Steven from the Netherlands
Happy new year!
Hi! Nice video!
I had a similar problem connecting a defective dandanator, i got fried TR4/TR5 (They are responsible for giving the -5v and +12) and lower ram in two zx spectrum!
Thank goodness I realized it was a Dandanator thing, otherwise I'll end up burning my entire spectrum collection 😅
Thank you :)
The links for setting the ROM are most likely soldered then the ROM was swapped. The links are either H or N, H for Hitachi ROM and N for an NEC brand ROM, it looks like the links were cut and then rotated 90 degrees to the other position.
They have different select lines but both have 2 lines. A 27128 has only 1 select line. The two original select lines need to be combined with an "OR" and that is what the 2 diode modification does. That one EPROM works is maybe because one of the pins is floating. While it may work now, if an input is floating it can crash anytime. I would not use it without the modification.
Your original ROM might be perfectly fine too, depend on if the chip tester knows how to enable it. And since there are 2 different ROM versions using a different method, maybe the tester is using the wrong one. When you so the EPROM mod then also the original ROM works, regardless of the type.
Thanks for the info :)
beautiful place!
Thanks for visiting
Some days you get the bear, and some days the bear gets you. You were lucky: there was a little of both today. From your video remarks, it looks like you may have found the issue, so do please follow up on this one.
Oh no. It worked, then no more. You will find and let us know in an upcoming video for sure. If one can repair this then it's got to be you.
Sure. I think I know what happened now.
Atari 400 Mini announced today!
I want one :)