My RTL-SDR stick is now inside it's tin submerged in Aldi's own brand cooking oil (other discount supermarkets are available) and it seems to work fine and drift appears to be reduced greatly, there is one issue that occurred however.
The Neutrik USB connector and BNC connector are both coated with silicone sealant underneath, though it does not react with cooking oil the connectors aren't properly sealed and leak by a small amount when the lid is pressed on, not good, to remedy this I have decided to use Sugru, which may require me to temporarily remove the lid of the can to deal with, around the outside edges of the connectors.
The stick has little noise (due to a mod to the cable between the "A" side of the Neutrik and the stick itself, the shielding of the tin, and, of course, the cooling, it is currently placed on my bedroom windowsill and connected using a high quality Belkin USB cable.
Reception wise so far, as I am temporarily utilising the Nagoya NA-771 antenna, has been GB3IR, PMR446 channel 1 (which I was using for some tests to check drift and at the same time was in use by children as is normally the case), CB channel UK19 (me again for drift tests), the PPM correction ONLY had to be reduced.
This whole idea came from SDR for Mariners and the author seems to be bang on the money here, the stick can't get that hot if in oil, refrigeration may help further.
To make the most of the SDR I will naturally need a better antenna, the NA-771 is a 2/70 antenna, meaning it is only any good in VHF and UHF frequencies, and doesn't make a good scanner antenna, so that may need rectification.
In the mean time I think it's best to stress test the stick in its new enclosure.
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