"and protect your analog meter with 2 diodes across the terminals."
While Bill correctly states that the diode will not work across most meters,
because the voltage will not be high enough, and does outline how to correctly
install the diodes, it seems that we have forgotten about the use of this
particular meter. The circuit has a large resistance which limits current.
Because current is limited, it can never exceed the current rating of the meter
- hence the diode protection is not necessary.
Current indicating meters on a high pot are never more than 50 ua fs (which
would be in the neighborhood of 1700 ohms), but they would be used only be if
more desireable 10, 15 or 20 ua meters are not available. The current limiting
resistors must be bulletproof. If they fail, the loss of the meter is almost
irrelevant.
73, Colin K7FM
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