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  • Replacement RAM

    From Frank H. Sapone@21:1/5 to All on Sat Nov 21 21:49:49 2015
    I may have posted about this various times in the past but the lines on
    my vectrex don't intersect properly and the problem has become much
    worse over the years to the point that some games are completely
    unplayable (Gravitrex being the worst). I replaced the capacitors a few
    years ago with new ones; and even replaced all the socketed ICs once the problem began just to rule it out.

    Years back, John D. thought it may be the I/O chip or the RAM. I think
    it's probably the RAM and looks to be the least painful to replace.

    Will this 2114 work? http://www.ebay.com/itm/NATIONAL-MM2114N-2L-1024-X-4-STATIC-RAM-Qty-2-NEW-/201470016162?hash=item2ee88c7aa2:g:geQAAOSwnGJWTkGM

    Has anyone else had this problem and rectified it in the past?

    Frank

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Computer Nerd Kev@21:1/5 to Frank H. Sapone on Sun Nov 22 21:26:26 2015
    Frank H. Sapone <fhsapone@windstream.net> wrote:
    I may have posted about this various times in the past but the lines on
    my vectrex don't intersect properly and the problem has become much
    worse over the years to the point that some games are completely
    unplayable (Gravitrex being the worst). I replaced the capacitors a few years ago with new ones; and even replaced all the socketed ICs once the problem began just to rule it out.

    Years back, John D. thought it may be the I/O chip or the RAM. I think
    it's probably the RAM and looks to be the least painful to replace.

    Will this 2114 work? http://www.ebay.com/itm/NATIONAL-MM2114N-2L-1024-X-4-STATIC-RAM-Qty-2-NEW-/201470016162?hash=item2ee88c7aa2:g:geQAAOSwnGJWTkGM

    Has anyone else had this problem and rectified it in the past?

    I believe those RAM chips should work as replacements, though unless
    you're Vectrex also hangs or produces other unexpected behaviour
    besides the misaligned graphics, I am inclined to suggest that
    the RAM isn't the problem. If it were, other symptoms would be
    very likely.

    Have you replaced the 4066B and LF347 ICs in the X Y and Z
    deflection output circuit (see schematic in Vectrex Service
    Manual pg. 31 (PDF page 34), "XV. Logic Board Schematic")?
    It could also be another component in this part of the
    circuit. Or one in the power board schematic two pages
    earlier in the manual.

    Have you checked that all the voltages are correct (make
    sure to take precautions against the high voltages in
    the monitor circuits when checking)?

    Are lines still drawn to the full area of the screen?
    Are they being "condensed" towards the center of the
    display? This could indicate a voltage problem in the
    monitor circuit, among other things.

    --
    __ __
    #_ < |\| |< _#

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Frank H. Sapone@21:1/5 to All on Sat Nov 21 21:52:50 2015
    Forgot to mention that I am also interested in adding sockets to the
    RAM. I never had to research my own sockets; so if someone knows a part
    number from mouser (or similar reputable distributor) or how to research
    it myself this would be appreciated.

    Frank

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Computer Nerd Kev@21:1/5 to Frank H. Sapone on Sun Nov 22 21:27:58 2015
    Frank H. Sapone <fhsapone@windstream.net> wrote:
    Forgot to mention that I am also interested in adding sockets to the
    RAM. I never had to research my own sockets; so if someone knows a part number from mouser (or similar reputable distributor) or how to research
    it myself this would be appreciated.

    Any generic 18pin DIP socket will be OK. There's no particular part number
    you need to look for as the pin alignment is well standardised.

    --
    __ __
    #_ < |\| |< _#

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Frank H. Sapone@21:1/5 to Computer Nerd Kev on Mon Nov 23 07:22:46 2015
    On 11/22/2015 4:26 PM, Computer Nerd Kev wrote:
    Frank H. Sapone <fhsapone@windstream.net> wrote:
    I may have posted about this various times in the past but the lines on
    my vectrex don't intersect properly and the problem has become much
    worse over the years to the point that some games are completely
    unplayable (Gravitrex being the worst). I replaced the capacitors a few
    years ago with new ones; and even replaced all the socketed ICs once the
    problem began just to rule it out.

    Years back, John D. thought it may be the I/O chip or the RAM. I think
    it's probably the RAM and looks to be the least painful to replace.

    Will this 2114 work?
    http://www.ebay.com/itm/NATIONAL-MM2114N-2L-1024-X-4-STATIC-RAM-Qty-2-NEW-/201470016162?hash=item2ee88c7aa2:g:geQAAOSwnGJWTkGM

    Has anyone else had this problem and rectified it in the past?

    I believe those RAM chips should work as replacements, though unless
    you're Vectrex also hangs or produces other unexpected behaviour
    besides the misaligned graphics, I am inclined to suggest that
    the RAM isn't the problem. If it were, other symptoms would be
    very likely.

    Have you replaced the 4066B and LF347 ICs in the X Y and Z
    deflection output circuit (see schematic in Vectrex Service
    Manual pg. 31 (PDF page 34), "XV. Logic Board Schematic")?
    It could also be another component in this part of the
    circuit. Or one in the power board schematic two pages
    earlier in the manual.

    Have you checked that all the voltages are correct (make
    sure to take precautions against the high voltages in
    the monitor circuits when checking)?

    Are lines still drawn to the full area of the screen?
    Are they being "condensed" towards the center of the
    display? This could indicate a voltage problem in the
    monitor circuit, among other things.


    If the 4066B is socketed (which I believe it is) then that has been
    replaced. It's been a couple of years since I played with it to find
    out why.

    I haven't measured any voltages, but if you know of good places to start
    I can try this.

    The games play fine with no lockups. Now, there was some oddness too if
    you run the test cartridge on the first screen with the grid on the
    second half of the screen one of the lines produces a double line.

    Frank

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Frank H. Sapone@21:1/5 to All on Thu Nov 26 17:13:23 2015
    No words of wisdom here? I really want to get back to playing this
    system again, but I'm just about ready to go off and buy another machine.

    Frank

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Frank H. Sapone@21:1/5 to Frank H. Sapone on Sun Sep 11 15:05:55 2016
    On 11/26/2015 5:13 PM, Frank H. Sapone wrote:
    No words of wisdom here? I really want to get back to playing this
    system again, but I'm just about ready to go off and buy another machine.

    Frank


    In case anyone is curious it ended up being those poly caps on the logic
    board. And I now own 3 vectrex systems and each one does indeed fail
    that test on the test cartridge with double lines in the center and that
    some lines fail to fully intersect perfectly on the distortion tests,
    and always in the same exact places.

    Frank

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)