RF Amp operating temperature
Earlier measurement reported by Alberto in LIGO-T10004-61-v1 based on the LM34 temperature sensor were lower than that shown by placing a calibrated thermocouple sensor directly on the heat sink by about 5deg C. The difference probably arose because the LM34 was located on a separate free-hanging copper sheet attached to the RF Amp by a single screw, resulting in a gradient across the copper strip. I tried to move the LM34 which was glued down, but broke the leads in the process. I then replaced it with another one mounted much closer to the heat sink and held it down with a copper-strip clamp. There is no glue involved and there is heatsink compound between the flat surface of the LM34 and the heatsink. Picture attached.
The picture also shows the new filters which have been put in place to reduce the harmonics. Note that the SBP-10.7 which was to go on the 11 MHz Demod output is located much farther upsteam due to space constraints.

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