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--- blog:2020-04-12:power_cable_resistance [2020/04/12 23:23] – va7fi
+++ blog:2020-04-12:power_cable_resistance [2020/08/07 13:03] (current) – external edit 127.0.0.1
@@ Line 35: / Line 35: @@
 </WRAP>
-The slope of the line is the resistance since: $R = \frac{\Delta V}{\Delta I}$, which in my case is 0.09 Ω.  Note also how much power is loss in the cable.  The booster helps maintain a constant 14V at the radio, but the total power used can be much higher because of the loss in the line.
+The slope of the line is the resistance since: \$R = \frac{\Delta V}{\Delta I}\$, which in my case is 0.09 Ω.  Note also how much power is loss in the cable.  The booster helps maintain a constant 14V at the radio, but the total power used can be much higher because of the loss in the line.
-A trick to help reduce this power loss is to add a smaller battery in the house.  The idea is that during transmit, some of the current will be drawn from that smaller battery.  Since less current will flow through the longer cable and the voltage drop will be reduced, the power loss will also be reduced.  Here's the same table again
+A trick to help reduce this power loss is to add a smaller battery in the house.  The idea is that during transmit, some of the current will be drawn from that smaller battery.  Since less current will flow through the longer cable and the voltage drop will be reduced, the power loss will also be reduced.  Here's the same table again when the small battery is connected:
-FIXME: to be continued.
+<WRAP indent>
+|<10px >|
+^ ^Current (A) ^Voltage Drop (V) ^Power Loss (W) |
+|5W    |2.8	|0.5	|1.4 |
+|12W   |4.8	|0.6	|2.9 |
+|25W   |5.2	|0.6	|3.1 |
+|50W   |7.3	|0.6	|4.4 |
+|100W  |10.8	|0.7	|7.5 |
+|>100W |16.7	|0.8    |13 |
+</WRAP>