Search found 39 matches

by FrancoisLanciault
Thu Jun 07, 2018 10:57 pm
Forum: The Off-Topic Section
Topic: Need electronic expert advice for a project
Replies: 13
Views: 739

Re: Need electronic expert advice for a project

This makes more sense now on the switch side of things. The switch enable will trigger that lower of the 3 comparator's (there are 4 in the 339 package), and that in turn will switch Q6 on, allowing the SW pin to rise towards +12V, it would normally be dragged to 0.6V by the bias resistor to -12V a...
by FrancoisLanciault
Thu Jun 07, 2018 6:20 pm
Forum: The Off-Topic Section
Topic: Need electronic expert advice for a project
Replies: 13
Views: 739

Re: Need electronic expert advice for a project

Thank you 1024MAK and Pr0f, your answers are definitely and better justified than anything I heard so far! The only remaining mystery is the fact that the switch circuit make sense only if the SW pin has a positive supply even though I have measured a negative voltage. Here is some description of th...
by FrancoisLanciault
Wed Jun 06, 2018 6:06 pm
Forum: The Off-Topic Section
Topic: Need electronic expert advice for a project
Replies: 13
Views: 739

Re: Need electronic expert advice for a project

One quick question - as this could be a showstopper for your project... What monitor or TV do you intend to use? Light pen will only work correctly with a CRT based TV or Monitor, as the LCD doesn't have a 'light spot'. Well, not only it needs a CRT monitor, but it needs the specific high resolutio...
by FrancoisLanciault
Tue Jun 05, 2018 5:53 pm
Forum: The Off-Topic Section
Topic: Need electronic expert advice for a project
Replies: 13
Views: 739

Need electronic expert advice for a project

Hi, I want to recreate the electronic inside a sophisticated light pen for a vintage computer. Nothing related to the QL hence the "Off-Topic" section. I have the original blue print of the electrical schematic. However, there are two or three things that can be interpreted one way or the ...
by FrancoisLanciault
Mon Apr 16, 2018 4:39 pm
Forum: Hardware
Topic: Problem at boot time
Replies: 12
Views: 820

Re: Problem at boot time

What happens when you swap the QLs between the two sets of expansions? Does the problem stay with the respective Gold Cards, or does it stay with the respective QLs? It would be difficult for me to test this because the SCG was modified to work with a backplane (I don't remember what modification I...
by FrancoisLanciault
Mon Apr 16, 2018 4:35 pm
Forum: Hardware
Topic: Problem at boot time
Replies: 12
Views: 820

Re: Problem at boot time

For me this looks like a bad contact somewhere (memory ?). I had a similar problem, it went away when I moved the SGC DRAM chips a little inside their sockets. Hi, Thank you all for your answers. Based on your experiences, I carefully removed all RAM chips from the SuperGoldCard, I inspected them a...
by FrancoisLanciault
Sat Apr 14, 2018 2:28 am
Forum: Hardware
Topic: Problem at boot time
Replies: 12
Views: 820

Problem at boot time

Hi, I currently have 3 QL systems, 1 Q68, 1 SGC + Aurora and 1 original QL + GC. The Q68 works perfectly :-) However, the other two are giving me troubles but only when booting: The Gold Card System problem is the following: When I power up the computer, it boots as it should i.e. first memory test ...
by FrancoisLanciault
Thu Feb 08, 2018 4:00 am
Forum: General QL Chat
Topic: SMSQzine #5
Replies: 8
Views: 1224

Re: SMSQzine #5

Ok thanks!

(Got the ZXzine too!)

Francois
by FrancoisLanciault
Wed Feb 07, 2018 5:18 pm
Forum: General QL Chat
Topic: SMSQzine #5
Replies: 8
Views: 1224

Re: SMSQzine #5

Just discovered your magazine. Very nice. How do I get the first 4 issues ??
by FrancoisLanciault
Thu Jan 18, 2018 10:13 pm
Forum: Software & Programming
Topic: TF Services I2C drivers
Replies: 6
Views: 590

Re: TF Services I2C drivers

Hi Dave,

I have a Minerva mk2 on my goldcard QL and have been using the I2C on a couple of projects. So if you have any question, let me know.

François

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