Dead IIe, wierd symptoms, need info

[gledford@fcircus.sat.tx.us (Gordon Ledford)]

    After letting it collect dust for a few years, a friend of mine turned
    on an Apple ][e and found that it didn't work anymore...  (It used to.)
    I measured the power supply voltages and they all looked good.  The LED
    on the motherboard near the power connector comes on, as does the
    `enhanced' light next to the keyboard.  However, there is no beep from
    the speaker, and the screen looks like some kind of systematic digital
    `snow.'  The video _signal_ is clean - it's the _content_ of the video
    signal that's wierd - quasi-random, quasi-systematic graphics that keep
    changing constantly, but every once in a while `slow down,' usually only
    briefly.  A control-reset causes a big slow down, but little pieces
    still fidget.  I don't think a control-apple-apple-reset has any
    particularly noticable effect.  These symptoms are with all cards
    removed including the 80 column card, by the way.

    Any ideas what's going on here?  My guess is that memory is somehow
    messed up, but since I don't know much about Apples, I don't know what
    to look at.  I poked around a little and found a few chips that seemed
    too hot to me.  One was the chip that's labeled `HAL' and another was a
    socketed LS device.  HAL appears to be a programmable device.  Does HAL
    usually get warm?  _How_ warm?  What else can I do to narrow this down?

    If someone has a ][e schematic they can scan and e-mail me that might be
    helpful also.  Any hints or references to good parts places will be
    appreciated.  (Besides Alltech - I called for a catalog weeks ago.)

    Thanks.

    Gordon Ledford                                gledford@fcircus.sat.tx.us