rubber_jonnie wrote: Thu Mar 13, 2025 3:47 pm
Well mine had green goo on the pins, and though I ended up removing the connector to clean in my ultrasonic bath and resoldering, but there was nothing I'd class as bad corrosion and as you know it turned out to be a bad RAM IC on the expansion board.
I'm sure it'll be fine. My clock/RAM board has a CR2032 so should be relatively immune from leakage now.
The working one doesn't have space for a battery, jut the 4x RAM chips, a switch and some resistor packs...
The other one I'm about to test did have a Varta but has allegedly been repaired...we will see...
Good luck with that
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
JezC wrote: Thu Mar 13, 2025 4:29 pm
Thanks @rubber_jonnie
I've removed the metal shield from the other trapdoor RAM and it's now being tested...detected OK as 1/2 MEG slow RAM...
It's up to round 10 of testing already so I'll leave it running for a while to see the results!
Good stuff. Is it an issue 6? If so you can boost the chipram with a trapdoor expansion quite easily.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
rubber_jonnie wrote: Thu Mar 13, 2025 4:49 pm
Good stuff. Is it an issue 6? If so you can boost the chipram with a trapdoor expansion quite easily.
Nope Issue 5 B52 Rock Lobster, same as you bought from me.
The other RAM card has now gone through more than 150 cycles (testing both 0.5 Meg blocks) so might be OK...can I be bothered to fit a battery for the RTC on it though?....
I might even get the last A500 out of its box to check if that can be resurrected as well...especially now I appear to have two working trapdoor RAM cards
rubber_jonnie wrote: Thu Mar 13, 2025 4:49 pm
Good stuff. Is it an issue 6? If so you can boost the chipram with a trapdoor expansion quite easily.
Nope Issue 5 B52 Rock Lobster, same as you bought from me.
The other RAM card has now gone through more than 150 cycles (testing both 0.5 Meg blocks) so might be OK...can I be bothered to fit a battery for the RTC on it though?....
I might even get the last A500 out of its box to check if that can be resurrected as well...especially now I appear to have two working trapdoor RAM cards
Well mine is a Rock Lobster, but I could have sworn it was issue 6. Will look next time I'm in it.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
rubber_jonnie wrote: Thu Mar 13, 2025 4:49 pm
Good stuff. Is it an issue 6? If so you can boost the chipram with a trapdoor expansion quite easily.
Nope Issue 5 B52 Rock Lobster, same as you bought from me.
The other RAM card has now gone through more than 150 cycles (testing both 0.5 Meg blocks) so might be OK...can I be bothered to fit a battery for the RTC on it though?....
I might even get the last A500 out of its box to check if that can be resurrected as well...especially now I appear to have two working trapdoor RAM cards
Good stuff
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
rubber_jonnie wrote: Thu Mar 13, 2025 5:13 pm
Well mine is a Rock Lobster, but I could have sworn it was issue 6. Will look next time I'm in it.
Maybe I'm struggling to read it properly under the label...but there are 16 RAM chips on the motherboard
And I am definitely not an Amiga expert by any means!
Oh, mine has 4 with space for another 4, Typical, I have no photos of that part of the board.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
JezC wrote: Thu Mar 13, 2025 5:38 pm
Sounds like I passed you the better one then
It's certainly possible.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
