I used that counter on a couple of my cams and not one of them still works. It seems that the LCD just cant handle sub 30 degree weather. At least that has been my experience. If you want to try one though I would give you this advice...
Call TruMeter directly and order from them. I got mine for $10.00 each instead of the $15.00 from RS.
I have a couple of brand new ones still if anyone wants them for $10.00 each and whatever it costs to ship them to you.
Did the displays actually go bad, or did the internal battery die? Thanks for the diode part #. I bought one a while ago, and I was thinking about putting it to use, I bought it from RS for $9.95, but now they don't have them anymore. I didn't know LCD panels were that temp sensitive. Otherwise I might add it to my next cam with hamiltoe's board.
(Edited by coyotebandit at 9:30 pm on Feb. 21, 2002)
I tried changing the battery without any luck. The didplays have discolored cracks in them so I assume the lcd's froze.
They worked great through the warmer weather, but once the temp dropped below 30 for a week straight they quit working.
I've looked over this circuit before, and I'd be wary of using it. Ideally, the camera and the counter should be *completely* isolated from each other. No damage can happen to the cam, but the counter could possibly be fried if one the diodes goes bad or one of the wires or diodes are hooked up wrong.
The diagram also shows the "counter positive" (I'm *guessing* this is a reference to the blue wire??) being momentarily contacted to the "battery holder" (which is the battery positive terminal) to reset the count. The Trumeter instruction sheet states to reset to zero by shorting the reset contacts - solder pads located on the counters PCB board that have no wires connected.
To isolate the cam and counter, use two relays - or one relay with two switches (a DPDT or DPST type). Or, for a cheaper, lower power option, use opto-isolators for the cam and counter.
The instructions state a storage temp range of -10 to +60C, or approx. +15 to +140F, use below +15F may well cause the LCD to freeze.