1. Carr is more readable.2. ARRL is more comprehensive, with 2.5 times the number of words as Carr.3. ARRL has more photographs and better looking sketches.3. ARRL has a multi-author approach (with technical checks and balances) as opposed to Carr's one-man approach. Carr contains few bibliographical references, whereas ARRL has tons of references for further reading.
My opinion: Carr is better for the beginner, but ARRL is better for details and as a reference book. Better yet, get both books, since they serve complementary purposes.
Design and construct your own antennas with step-by-step instructions and plans. Joseph J. Carr?s Practical Antenna Handbook, Fourth Edition, is an update of the most popular book on antennas ever written. This empowering guide blends theoretical concepts that engineers need to design practical antennas with hard-learned lessons derived from actually building and using antennas -- real antennas, not merely theoretical constructs on a blackboard. Certain to become the toolbox favorite of radio enthusiasts and professionals of all types, from technicians to citizen banders and shortwave listeners, it covers a wide variety of antennas: high-frequency dipole; vertically polarized HF; multiband and tunable wire; hidden and limited space; directional phased vertical and directional beam VHF/UHF transmitting and receiving; shortwave reception; microwave; and mobile, marine, and emergency. This state-of-the-art edition includes a new chapter on antenna modeling software and new coverage of small transmitting antennas and receiving loop antennas.
*Packaged with CD-ROM with antenna modeling software -- including material on EZNEC for Windows 3.0.