Search found 19 matches

by Vyper68
Thu Jul 19, 2018 5:02 am
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

OK
I will see if can contact him on Amibay and get some help, thanks.
by Vyper68
Wed Jul 18, 2018 6:25 am
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

Well i have replaced IC11, fitted a new LM1889N, replaced all the Electrolytic caps on the Power Board and CPU Board, I have replaced the Tantalum capacitors on the board, replaced RV1, replaced C7, replaced the Ceramic Caps on the Chroma output feed just in case. I swapped out the SAM and it wasn't...
by Vyper68
Fri Jul 13, 2018 9:49 am
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

This issue 2 is really early too the date code for the chips are week 44 1982 there are only 8 OKI chips as well. That sounds like one of the boards using "half good" 64K chips. Those are the easiest boards to upgrade to 64K. Cheers. Phill. Nice... Anyone got a link for the project please. Richie. ...
by Vyper68
Fri Jul 13, 2018 9:30 am
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

This issue 2 is really early too the date code for the chips are week 44 1982 there are only 8 OKI chips as well. That sounds like one of the boards using "half good" 64K chips. Those are the easiest boards to upgrade to 64K. Cheers. Phill. Nice... Anyone got a link for the project please. Richie.
by Vyper68
Thu Jul 12, 2018 5:05 pm
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

I have tried the power board and PSU from the fully working Issue 2 in the Issue 6 and that had no effect. I have replaced the Electrolytic Caps on the Issue 6. I was going to replace the Caps on the Power Board as well but it seems that wasn't needed ( still might do it though ) The PSU's check out...
by Vyper68
Thu Jul 12, 2018 2:35 pm
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

I think i might be getting somewhere now... I have just bought another D32 ( this one is permatanned but came with Ghost Attack and some tapes ) - This is an Issue 2 Board with RV1 and RV2 ( this is the important part ) If i adjust RV1 on this Issue 2 Dragon too far i can get the same output as the ...
by Vyper68
Wed Jul 11, 2018 1:28 pm
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

Well that was disappointing, i fitted a new LM1889N and the problem is still there. Does anyone have any ideas where to look next? In the meantime i am going to replace all the electrolytic capacitors on the Power and Main PCB's i may also replace the Voltage regulators as well. Does anyone have a l...
by Vyper68
Tue Jul 10, 2018 6:38 am
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

I didn't explain that very well: I should have clarified that the pad isn't connected to anything, so it wouldn't make any difference whether the pin is soldered or not. All the pins are normally soldered in so I guess something odd happened during production or there was some experimentation in th...
by Vyper68
Mon Jul 09, 2018 8:40 pm
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

sorchard wrote:
Vyper68 wrote:Would the VDG carry on with Pin 20 disconnected ... ?
Pin 20 of the vdg is an unused output and should be left unconnected.
Well that is something i have not come across before so that's filed away for the future. :oops:
by Vyper68
Mon Jul 09, 2018 6:12 pm
Forum: Dragon General
Topic: Sick Dragon 32
Replies: 36
Views: 4414

Re: Sick Dragon 32

Hi Thanks for all the responses they greatly appreciated. I had the main PCB off to check underneath for any obvious bad solder joints, and to try and trace some of the lines for the Video circuit and it does look like i'll have a problem tracing this fault if the LM1889N is not the problem. I have ...