Brent Cooley
TVWBB Member
I had my HM 4.1 working like a champ. I had applied the "white wire mod" for the ground connection and added a ground connection to each of my ET732 probes. I also replaced 3 of the 4 resistors for Pit,food 1, and food 2 to 22k to better work with those probes.
Everything worked flawlessly for weeks, even reading fine at basement temperatures in the lower 60s.
Recently, I noticed the Pit temp acting very strange and sporadic and I'm not exactly sure why.
Some symptoms:
* Even with no probe inserted, Pit temp will spontaneously read 300-600 degrees and somewhat "cycle" through that range.
* With probe inserted, sometimes reads 0 for a few seconds, then repeats the above
* Tried different probes in Pit jack- same results. Same probes read fine in Food1,food2 even while Pit is reading wacky
* Tried without r Pi attached - same results
* I never see the "No Pit Probe" message anymore. Even when things aren't wacky, it'll show 0 degrees when no Pit probe is plugged in (rather than "No Pit Probe")
Then...
* Tried pressing on the HM board in certain places... Sometimes this gets it to stop and read normally. If I don't touch it from then on, it'll work fine for hours.
* If I put it all in the case and lightly shake it around, Pit temp will go wacky then return to normal when I stop.
All this sounds like some sort of bad connection, but if I read the schematic properly, the only things "in play" for reading the Pit temp are the ATMega, probe jack, and a resistor. My plan is to unsolder and replace the Pit jack, Pit resistor and reseat the ATMega.
Anyone ever seen something like this or could suggest anything else to test or try to narrow it down? Is there anything different about the Pit probe connection than the other 3?
Everything worked flawlessly for weeks, even reading fine at basement temperatures in the lower 60s.
Recently, I noticed the Pit temp acting very strange and sporadic and I'm not exactly sure why.
Some symptoms:
* Even with no probe inserted, Pit temp will spontaneously read 300-600 degrees and somewhat "cycle" through that range.
* With probe inserted, sometimes reads 0 for a few seconds, then repeats the above
* Tried different probes in Pit jack- same results. Same probes read fine in Food1,food2 even while Pit is reading wacky
* Tried without r Pi attached - same results
* I never see the "No Pit Probe" message anymore. Even when things aren't wacky, it'll show 0 degrees when no Pit probe is plugged in (rather than "No Pit Probe")
Then...
* Tried pressing on the HM board in certain places... Sometimes this gets it to stop and read normally. If I don't touch it from then on, it'll work fine for hours.
* If I put it all in the case and lightly shake it around, Pit temp will go wacky then return to normal when I stop.
All this sounds like some sort of bad connection, but if I read the schematic properly, the only things "in play" for reading the Pit temp are the ATMega, probe jack, and a resistor. My plan is to unsolder and replace the Pit jack, Pit resistor and reseat the ATMega.
Anyone ever seen something like this or could suggest anything else to test or try to narrow it down? Is there anything different about the Pit probe connection than the other 3?