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  1. The PIA C7 may be bad.

    The PIA C7 may be bad.
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    We’ll need to check the recorded checksums from...

    We’ll need to check the recorded checksums from pettiest vs the known good values, as a ROM maybe bad. I forget, do you have new ROM installed or originals?
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    Yes, daver2 did great job. Kudos for skill and...

    Yes, daver2 did great job. Kudos for skill and patience.
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    It passed the quick RAM test and did a sum check...

    It passed the quick RAM test and did a sum check on the ROMs.

    If you like, you can replace the pettest rom with the EDIT rom and see if it boots. We may need some more testing.
  5. That is pin 12, the ground connection. It is...

    That is pin 12, the ground connection. It is required for the chip to work. Did you solder the pin back on? Or at least tack a wire from the shoulder of the chip to the socket pin. Try not to mess up...
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    I see what you are saying. The stuck shift...

    I see what you are saying. The stuck shift register lines may mess up timing to the row scan signal of RAM and also the Video Latch signal.
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    Hi Il Paninero, This is not right to get exact...

    Hi Il Paninero,
    This is not right to get exact same results with a 2532 and a 2716 EPROM in the EDIT socket. I suspect a bad socket. Can you replace the D8 EDIT ROM socket or at least give it a...
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    Congratulations! Excellent troubleshooting...

    Congratulations! Excellent troubleshooting procedures.
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    We spent two weeks in the wilds of New Mexico...

    We spent two weeks in the wilds of New Mexico chasing Billy the Kid and exploring the Santa Fe Trail. Attached is a map of an American Civil War battle site (Battle of Glorieta Pass) fought in 1862...
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    A 2532 EPROM will not work in the EDIT ROM socket...

    A 2532 EPROM will not work in the EDIT ROM socket in a 3032 PET as it will step on the I/O address space (E800-E840). This problem was fixed in the 4000 and 8000 PETs. By coincidence of pinouts, a...
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    Il Paninero, I have been on vacation for a...

    Il Paninero,
    I have been on vacation for a couple of weeks. There maybe other issues, but your lower 16K RAM is a good candidate for replacement. Please take your time with good solder joints. It...
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    Dave, Good plan. Paninero, it is required to...

    Dave, Good plan.

    Paninero, it is required to leave the NOP Generator installed for the chip select decoder test.
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    It looks like Paninero now knows how to use his...

    It looks like Paninero now knows how to use his scope. But before looking into his possible bad low RAM, did we have him use his Voltmeter to check the -5V and +12V of the dynamic RAM chips. I can't...
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    So the only problem was the F7 video RAM? So...

    So the only problem was the F7 video RAM? So Dwight was correct that the several problems seen on the screen that looked like addressing issues were all internal to the RAM chip containing the upper...
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    That is a good idea. A divide by 100 circuit...

    That is a good idea. A divide by 100 circuit would get a reasonable frequency check on signals over 2 MHz.
  16. Yes, but it is for the cassette port. How would...

    Yes, but it is for the cassette port. How would they know one would not need to use the cassette port?
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    Yes, the effective bandwidth of that scope is...

    Yes, the effective bandwidth of that scope is very limited. It will be OK for the 20 KHz video timing circuits, but not for CPU digital pulses in the 1 MHz region.:(
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    Yes, the scope display is very clear. ...

    Yes, the scope display is very clear.

    Paninero, please can you post one for Sync signal? (CPU pin 7). I think it should be around 250 KHz with a 25% duty cycle. It indicates proper fetching of the...
  19. Photo of adapter, please.

    Photo of adapter, please.
  20. Here is a source for the 8032 schematics, parts...

    Here is a source for the 8032 schematics, parts list, and top assembly : http://www.zimmers.net/anonftp/pub/cbm/schematics/computers/pet/univ2/index.html
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    Yes, they look OK.

    Yes, they look OK.
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    No, that's Dave Curran. However he and our daver2...

    No, that's Dave Curran. However he and our daver2 are both very technically sharp British men!
    -dave_m (non British and non technical from SoCal!)
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    Dwight, The symptom of inverse video on every...

    Dwight,
    The symptom of inverse video on every odd screen address is trying to tell us something, but what? The Latched Screen Bit 7 must he high on very odd address. I could go with a possible bad...
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    Certainly worth a shot. Before unsoldering,...

    Certainly worth a shot. Before unsoldering, perhaps a piggyback test on F8 with a spare 2114 to see if anything changes?
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    Dwight, Good post! I was hoping for a bad RAM...

    Dwight,
    Good post!
    I was hoping for a bad RAM address MUX too, but Fran's clear scope videos shows these signals looked at are good. If the problem is a broken trace, Fran will need patience and a...
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