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GQ provided me with a "GMC 600 Plus" Firmware-Update relating to CPM-Pulse-Data through the Data-Port thereby eliminating the need for the Audio-Port and Audio-Cable if/when desired. In My Opinion, this is a much, much more accurate way of obtaining CPM-Pulses ... After the Update, I needed to restart/reboot both "GMC 600 Plus" units.
( i.e. both GMC displays now perfectly match the window of NetC's software at the end of each minute! )
I did not stop the NetC data-collection and upon reboot of the units, an unexpected data transmission occurred creating an 8800-ish CPM data-spike to both of my NetC datasets ... so I chose to Delete both of my NetC-datasets.
Both of my "GMC 600 Plus" Units containing LND-7317 Geiger-Tubes are now within 6-inches of each other, horizontally facing down, 2-inches above a heavy-plastic folding table, and with and indirectly-pointed 6-inch personal-fan 2-feet away to guarantee air-flow around both units at my location in Montrose, Colorado, USA.
Farley
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