Nice debug work there. It is an example of the kinds of defects that can show up over time. I think t t good close inspection of the board can help to track down the culprit.
I have more that 20 modelTs and less than half work reliably. On Monday, December 28, 2015, Geoffrey Oltmans <[email protected]> wrote: > And by checking the RAM power, I mean, at the power pin on the RAM itself, not at the terminals on the Nicad battery. > On Mon, Dec 28, 2015 at 8:31 AM, Geoffrey Oltmans <[email protected]> wrote: >> >> I bought a fixer upper Model 102 not too long ago. What I discovered on that was that not only was the Nicad battery dead (not unsurprising), it would not power the RAM while turned off because battery acid from the old battery had leaked down the side of the board and etched a hole through the trace that would allow it to do so. The RAM would power on while the power switch was on, but with the memory back up switch in the on/off position it made no difference. I would suggest checking for this... check to see if you have power to the RAM while the power switch is down. There is a long trace on the edge of the circuit board that supplies this backup power and in my case I had to wire a short jumper to bridge the etched out section. All is well now. >> On Mon, Dec 28, 2015 at 7:21 AM, Todd Felmly <[email protected]> wrote: >>> >>> Yes. I had the case open and a meter shows 4.2 volts with the power brick unplugged. >>> >>> On Dec 28, 2015 1:50 AM, "Peter Vollan" <[email protected]> wrote: >>>> >>>> Are you quite sure that the internal nicad is charged up? >>>> >>>> >>>> On 27 December 2015 at 19:31, Todd Felmly <[email protected]> wrote: >>>> > Sadly that didn't make a difference. >>>> > >>>> > When powered on the month on the RTC is sometimes scrambled but resetting >>>> > usually brings it back to normal if that makes a difference. >>>> > >>>> > On Dec 27, 2015 7:40 PM, "John R. Hogerhuis" <[email protected]> wrote: >>>> >> >>>> >> Your nicd may also be low. Leave it on charger for several hours then >>>> >> withhold all power including memory switch for 10 minutes. Then power it up >>>> >> and do cold start. >>>> >> >>>> >> -- John. >> > >
