Replacing all the caps! No Way!. Maybe testing a few.
If you have dual trace scope with trigger, you can look to see if the CPU
is resetting. If not, I would suspect this small circuit. Note the timing
admonition on the schematic!
Copy attached. Let us know. My 565 still needs repair!
73, -Bob
> > On Aug 5, 2016, at 11:09 AM, Katz Ajamas <ajamas.rn@gmail.com> wrote:
> >
> > So what was wrong? CPU power on reset problem? Please share.
> > 73, -Bob ah7i
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
>
>
>
> ------------------------------
>
> Message: 5
> Date: Fri, 5 Aug 2016 22:47:32 -0500
> From: Gary J FollettDukes HiFi <dukeshifi@comcast.net>
> To: Discussion of Ten-Tec Equipment <tentec@contesting.com>
> Subject: Re: [TenTec] Orion II repair
> Message-ID: <0141B9C2-28C8-4211-BE27-3DA03028E199@comcast.net>
> Content-Type: text/plain; charset=utf-8
>
> To clarify, for the more well advance EE?s out there, what I called an I/O
> controller is actually a complex programmable logic device (CPLD).
>
> It is, however, so far as I can tell, acting as traffic cop for the CPU.
>
> Gary
>
>
> > On Aug 5, 2016, at 10:19 PM, Gary J FollettDukes HiFi <
> dukeshifi@comcast.net> wrote:
> >
> > I still don?t know.
> >
> > Here is an update o the rather strange behavior:
> >
> > I already swapped power distribution board, button board and CPU board.
> A different CPU board operates properly in the radio. perfectly.
> >
> > Here is the sequence:
> > 1) Cold startup normal boot up sequence, receives signals, none of the
> encoders except VFO?s work, none of the pushbuttons work.
> > 2) Connect to N4PY software and connect, most functions work but not
> necessarily correctly. Tuning rate is very slow and some buttons do not do
> what they should.
> > 3) Shut down for maybe 30 minutes.
> > 4) Cold startup normal boot up sequence, receives signals, none of the
> encoders except VFO?s work, none of the pushbuttons work.
> > 5) Wait 15 minutes, everything works fine.
> > 6) Shut down for maybe 30 minutes.
> > 7) Cold startup normal boot up sequence, receives signals, none of the
> encoders except VFO?s work, none of the pushbuttons work.
> > 8) Wait 15 minutes, everything works fine.
> >
> > Now, if I operate the encoders while the radio is ignoring them, then
> wait out the 15 minutes, the radio responds just as if I had just taken
> those actions. That is, if I turn the volume down while the radio is not
> responding, the volume will drop once the radio starts working. Ditto for
> all other encoders. So data is getting to the I/O controller, just not
> being sent to the CPU. In this state, the actions of pushbuttons are NOT
> saved, however.
> > One thing that is different about the VFO encoders, both of which always
> work, and the 6 small encoders is that the VFO encoders are pull high
> devices operating from the R5 volt supply. The 6 small encoders are pull
> down devices with outboard pulp resistors also operating from the R5 volt
> supply.
> >
> > If I operate the encoders in the first fractions of a second after boot
> up, before the S meter makes is normal bump swing to the right, the
> encoders work but stop working after that bump.
> >
> > The delay to normal operation is pretty repeatable. It acts as if there
> is a high resistance somewhere and a capacitors is charging up to enable
> the CPU to see data that is in the I/O controller.
> >
> > I really doubt that this is a thermal issue or a CPU or I/O controller
> issue. I am contemplating simply replacing all of the capacitors on the CPU
> board.
> >
> > Gary
> >
> >
> >
> >> On Aug 5, 2016, at 11:09 AM, Katz Ajamas <ajamas.rn@gmail.com> wrote:
> >>
> >> So what was wrong? CPU power on reset problem? Please share.
> >> 73, -Bob ah7i
> >> _______________________________________________
> >> TenTec mailing list
> >> TenTec@contesting.com
> >> http://lists.contesting.com/mailman/listinfo/tentec
> >
>
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