 |
 |
|
|
|
|
|
|
||||||||||||||||||
|
|
|||||||||||||||||||
|
|
|||||||||||||||||||
|
|||||
|
|
There are several typographical errors in the first printing of the 5th edition of The ARRL General Class License Manual. On page 7-8, in the last paragraph before the heading "Power Supply Overvoltage Protection -- The Crowbar Circuit" there is some missing text. That paragraph should read:
It is important to use filter capacitors that have a low equivalent series resistance (ESR) rating for the output filter of a switching power supply. The capacitors will have to handle the large current pulses, and if their ESR is too high they will not charge to the full output voltage. That will increase the output ripple voltage of the supply.
The last sentence on page 7-8 should read:
Figure 7-8 is the schematic diagram for a simple crowbar circuit.
On page 9-10 there are several errors in the way the calculation for the length of the driven element of a Yagi antenna for 21.1 MHz is shown. Beginning with the first equation near the top of that page, the corrected text is:
Next, use Equation 9-2 to calculate the approximate director length:
(Yagi) LDirector = LDriven × 0.95
(Yagi) LDirector = 22.2 ft × 0.95 = 21.1 ft
This is approximately 21 ft.
There is a typographical error in question G6A14 as released by the Volunteer Examiner Coordinators' Question Pool Committee. This question is printed on page 13-59. Answer choice D should read:
D. Between its enhancement and depletion modes
The Volunteer Examiner Coordinators' Question Pool Committee has withdrawn question G8A06 from the question pool. This was necessary because of a change to the FCC Rules, Section 97.307 (d). Question G8A06 is found on page 13-63. In addition, it is referenced in the gray "study questions" box on page 8-7. Also in that gray box on page 8-7, you are directed to study question G9B12. That should be G8B12.
