From: Gabriele Bozzi (mabuse68_at_gmail.com)
Date: 2006-06-10 13:51:23
Hi,
Before going deep into "digital" or signal generation my humble advice
is to check the high voltage section for cold soldering or broken
contacts.
As I mentioned before: check for good contact on each of the high
voltages coils on the video ramp signal as well as eventual exploded
capacitors.
Eventually checkong for signals: do not try to use an oscilloscope
there since the impedance of the probes gather signals already from
20cm away :) You need usually to trigger to vertical signal.. (am I
right? vertical? It's a hell of a time thet I do not repair a video
...).
Have a nice weekend.
Gabriele
On 6/10/06, r.lagendijk@hccnet.nl <r.lagendijk@hccnet.nl> wrote:
> Hello,
>
> I put a 4032-32N next to my 2001, connected the 2001 monitor to the 4032
> motherboard and I got a normal screen display (4302). It's a bit bright
> but it's the display is full screen.
>
> I think that the video circuit of the 2001 is not working correctly.
> I presume it starts at the upper left corner. Gets a bit from the shift
> register B2, the beam moves a bit to the right another bit is fetched and
> so on.The beam moves a line down and starts again. Eventually it goes to
> the bottom right corner.
>
> I'm thinking that the "counting or setting" of the lines does not work
> anymore except for the 3rd quarter of the screen. It could be that the
> charROM is not perfect but I don't have a 6540 that I know it's perfect to
> swap.
>
> I'm trying to understand the "counting or setting" of the lines but the
> schematics are to complex for me.
>
> Also there is a BLANK signal at E9 (Last NAND before the monitor
> connection) is this to shutdown the beam to prevent flyback to be visual
> on the screen? Could it be that somehowe the BLANK signal stays on too
> long (first and last part of screen?) BLANK comes from G8 (CA2 / PIA#1)
> Or is it used as in a C64 to just blank the whole screen.
>
> I noticed ther are a lot ot testpoints on the schematics. (TP5-1, TP2-1
> and so one) Is there a manual how these work, I think that they are point
> you can ground and a certain effect can be seen. Most of the testpoints
> are pulled up to the 5VDC with a resitor.
>
> greetings Richard
>
>
> Op Vr, 9 juni, 2006 7:34 am schreef ruud.baltissen@abp.nl:
> > Hallo Richard,
> >
> >
> >
> >> I would say that, first of all, some issues with vertical
> >> deflection are there.
> >
> > I second that.
> >
> >
> >
> >> Furthermore: on the user port of the PET you can extract a composite
> >> video signal.
> >
> > That is a good option, but may be a better one: what about connecting
> > anpther CBM monitor? IIRC the 2001 has the same pinouts as all newer CBM
> > series so you should be able to connect thew monitor of a CBM 8032 for
> > example.
> >
> >
> > --
> > ___
> > / __|__
> > / / |_/ Groetjes, Ruud
> > \ \__|_\
> > \___| URL: Ruud.C64.org
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > =====DISCLAIMER==========================================================
> > =======
> >
> >
> > De informatie in dit e-mailbericht is vertrouwelijk en uitsluitend
> > bestemd voor de geadresseerde. Wanneer u dit bericht per abuis ontvangt,
> > verzoeken wij u contact op te nemen met de afzender per kerende e-mail.
> > Verder verzoeken wij u in dat geval dit e-mailbericht te vernietigen en
> > de inhoud ervan aan niemand openbaar te maken. Wij aanvaarden geen
> > aansprakelijkheid voor onjuiste, onvolledige dan wel ontijdige
> > overbrenging van de inhoud van een verzonden e-mailbericht, noch voor
> > daarbij overgebrachte virussen.
> >
> > The information contained in this e-mail is confidential and may be
> > privileged. It may be read, copied and used only by the intended
> > recipient. If you have received it in error, please contact the sender
> > immediately by return e-mail; please delete in this case the e-mail and
> > do not disclose its contents to any person. We don't accept liability for
> > any errors, omissions, delays of receipt or viruses in the contents of
> > this message which arise as a result of e-mail transmission.
> >
> >
> >
> > Message was sent through the cbm-hackers mailing list
> >
> >
>
>
>
> Message was sent through the cbm-hackers mailing list
>
--
***********************************************
Gabriele Nicola Bozzi
SANAE VoF Beveren - Belgie
A: Maybe because some people are too annoyed by top-posting.
Q: Why do I not get an answer to my question(s)?
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
***********************************************
Message was sent through the cbm-hackers mailing list
Archive generated by hypermail pre-2.1.8.