EMRFD Chapter 6 Errata.   
  (8 Nov 10)

p6.11, middle column, 2.0 inches down from text top:  replace "An NF of" with "A NF of"     (9Dec03)

p6.14.  Fig 6.37.  The figure was missing the reference designators used in the caption.  The updated figure is shown below.  (17Mar03)

p6.18, Fig 6.46.   The resistor between +12 and L1 should be 47 Ohms.    (3April10)  

p6.20.   Fig. 6.50.  The text line in the lower left corner should use the phrase "designer/builder."   (31July09) 

p6.28 Left col, bottom, one line up.    "it's own" becomes "its own".     (29Aug9)    

   Fig 6.37      (9 Dec 03)   Note:  The first version of this figure we had on the web was wrong. The "pull-up" resistor to +12 V should go to Q2 rather than to the anode of the diode.   The circuit in the 2nd printing of EMRFD is NOT correct.   It is still wrong in the 3rd printing.     The proper circuit is that shown above where R9 serves to put a positive bias on Q2 and a reverse bias on the diode in the no attenuation condition.   This resistor also biases the Q1 gate to a positive voltage to turn Q1 on.   When Q2 is turned on, it becomes an RF short circuit AND changes the DC conditions to cause Q1 to become an open circuit.   (17 April 09)


p6.37, left col, 1.1 inch down from top.   "it's" becomes "its".       (29Aug9)  

 p6.37, Fig 6.75.   Change a resistor from 3.6 to 6.8 Ohms.
 (10Feb10)      

p6.51, Fig 6.94.    There is an error in the input transformer in the schematic.   The original is partially shown here:
 This is the WRONG circuit.    Only the first FET is shown here, but there are four JFETs in parallel.  The original schematic shows the gate as being at the 5th turn on a 6 turn transformer.   In reality, the gate is across the full transformer while the input is applied to the tap.    The new, correct schematic is below:

Corrected Fig 6.94.    The data in the text was obtained from the circuit shown above.   That is, the thing was properly built, but the schematic was in error.       (22March08)   (Still in error in 3rd printing, 13April09)    


p6.53, 3rd column, 3 inches down from top.  Replace "receives" with "receivers"     (3Dec03)

p6.57, col 3, just above Transmitter IF Systems section.   The final sentence should become "A project elsewhere in the book (Fig 6.152) uses this topology with a diode ring balanced modulator."  (10Aug03)    

p6.87, Fig 6.152.  The figure contains a mixer in the lower right corner.   Directly above that mixer is a network of three resistors leading to a coax connector.   The 10 Ohm resistor should be changed to 18 Ohms to make it be a 3 dB pad.    (8Nov10)