826: Many old radios use an OA2 tube as part of their circuitry. The OA2 is a __________.

827: Of the following what is the best SWR match for an antenna?  

828: What device can be used to match an antenna manually or automatically?   

829: At what distance is the E layer of the ionosphere located?

830: How many layers are found in the Ionosphere?

831: On what date did the FCC remove the Morse code requirement from the Technician exam?

832: Of the following, what phrase is sometimes used when ending a voice communication on Ham radio before the call sign?    

833: Who developed the system of dots and dashes used for Morse code in the year 1838?

834: What is needed between a transceiver and an antenna?  

835: Alaska is in the region 11 call district. Of the following, what prefix does not belong?

836: In the WWII Command Set Receivers,(BC-455, etc) what tube was used in the RF and IF stages?

837: The prefix "7S" is assigned to what country?  

838: When was the 40 Meter band excluded from exclusive use for HAM radio?

839: Which Yaesu radio used the most vacuum tubes?

840: In what year did the F.C.C. give approval for hams to legally receive outside their frequency range?    

841: What was the model number of the first Heathkit® amateur transmitter kit offered for sale?  

842: A cage dipole antenna is

843: A shunt fed tower is used

844: Can the 2-meter band propagate a signal over 500 miles?        

845: If an antenna is to be an efficient radiator, it must be resonant at the operating frequency

846: Everyone refers to PL® tones these days that one uses to access some repeaters. What do the letters "PL" stand for?    

847: How many radials are needed to minimize ground losses for a ground mounted vertical.

848: In 1936, Pittsburg, PA was in which call district?

849: An old timer you know claims he once held the Ham call, W2ZZBZ. Possible?

850: How can a single-sideband phone signal be generated?