On Fri, Mar 28, 2025 at 06:12 PM, VE6WMR wrote:
Jay,
I have two 2465's here, and they're known for quite a few gremlins, including
NVRAM battery issues, among other problems.
Comparing a 2465 to a 2247A is a bit like apples and oranges, but understood the well meaning intention to be helpful in the sense that both are old.
But for one luckily the 2247A does not rely on NVRAM to store cal constants.
As suggested check all voltages and ripple to make sure they are within spec.
Also while you are in there, check power supply diodes, and any with ZM or ZS markings needs to be replaced as they are known to get leaky over time and cause problems. There are 17 of these diodes on the 224x (and 2252 same series) scopes power supply. Use fast diodes like MUR160 (600V 1A) or similar. Do not use common 1N400x.
Also replace the 3V Lithium battery, its only meant to hold the setting of the last session, no calibration at risk.
I have both 2465B and 2247A scopes, but the 47A is usually my go-to scope 95%.
