I calculated on paper using mesh analysis that I(V1) should be 0.716A Why does LT-Spice give such a weird result?
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The reason for this is explained in the LTspice Help under B. Arbitrary Behavioral Voltage or Current Sources. The relevant section is pasted below, but here's a web-link to a cached version of that help section.
Circuit element currents; for example, I(S1), the current through switch S1 or Ib(Q1), the base current of Q1. However, it is assumed that the circuit element current is varying quasi-statically, that is, there is no instantaneous feedback between the current through the referenced device and the behavioral source output. Similarly, any ac component of such a device current is assumed to be zero in a small signal linear .AC analysis.
Since your circuit is linear, you should be using an F-source instead. This requires an additional 0V voltage source in the circuit branch you want to reference, as shown below. See the help page for F. Current Dependent Current Source for more information.
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\$\begingroup\$ Thank you this is a wonderful answer! \$\endgroup\$– KevinCommented Feb 25, 2021 at 3:56
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\$\begingroup\$ @Kevin Forgive me if I'm misunderstanding your question, but there are 4 linear dependent sources: E-source (voltage->voltage), G-source (voltage->current), H-source (current->voltage), and F-source (current->current). Search the Help for each of those letters for more information. B-sources should be avoided if you can. \$\endgroup\$ Commented Feb 25, 2021 at 4:09
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\$\begingroup\$ I still got one more question left. I didn't see there is any linear voltage dependent voltage/current source. Does it mean that I could use "bv" without problem? \$\endgroup\$– KevinCommented Feb 25, 2021 at 4:11
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\$\begingroup\$ @Kevin You got it, brother. \$\endgroup\$ Commented Feb 25, 2021 at 4:15