I'll think about it overnight, but there are some other things that cancause this.
At 06:12 PM 4/6/2015, you wrote:
Mark,
I am still unable to get a print started... With the carrier removed thePin (Pad) 5 to GND values are 5.02V and 80mV. in passing the hole, itswitches between 5.02 and 126mV, only if perfectly centered (both X &Y) on the led. This implies that the hole is too small. so I re-drilledthe 0.026" hole to 0.030" and shimmed the sensor to exactlycenter the X dimension. I now have 5.02V & 90.2mV. which I expect tobe good... Nevertheless, I paralleled a 5600 ohm discreet across the 30kresistor, with a resulting resistance reading of 4.76k.
After pressing X with a good pull-in (no jam indicated) and thenexecuting a print command, I still get a paper jam, with thecarrier stopping with the trigger hole 0.55" to 0.65" past the CL of the sensor. I can then block the sensor and press continueto have the machine eject the carrier. Recycling power will restore thenormal state. Any ideas?
Perhaps I should replace the board... I don't have means tore-program.
Thanks,
Roger
On 4/6/2015 5:31 AM, Mark Lermanmlerman@...[Homebrew_PCBs] wrote:
Roger,
Sorry about the resistor. The 30K was used in a previous version thatused a reflective sensor - It should be about 5K. The higher resistorshould work (I think), but it will be more susceptible to noise. If yousend it back I will be happy to replace the resistor. If you prefer I canjust send you a new resistor and you can replace it yourself.
To see if it is the resistor, turn the machine on and put avoltmeter from ground to the sensor's collector (the end of the resistorNOT connected to the 5 volt supply). With the carrier blocking thesensor, it should read 5 volts. When the hole reaches the sensor itshould drop to near 0 volts, then go back up after the hole passesthrough. Do this by manually moving the carrier because it might be hardto see without a scope in real time.
Mark