Topband: VE3OSZ article on QEX may/june 2005

Robert Kavanagh ve3osz at
Thu Jul 7 13:04:51 EDT 2005

Enough topband people have asked me for a list of the corrections to the 
schematic in my PLL article that I hope Bill will allow me to use the 
topband reflector to inform interested persons about these errors.  Here 
are the changes to be made:

In Figure 4, in the section of the schematic involving U1 and the adjacent 
1/2 U2, the following corrections should be made:

1.      the 1000 pF capacitor should be shown connected between pins 7 and 
8 of U1.

2.      the 47k resistor above 1/2 U2 should be connected between pins 6 
and 7 of the 1/2 U2.

3.      pin 8 of U1 is NOT connected to pin 6 of the 1/2 U2.

In addition, there is one other error which is not mentioned in my letter 
to QEX:

4      there should be a 3k resistor in the line connecting the output of 
the lower half U3 to the inverting input (pin 2) of the upper half U3.

My thanks to Don, N7AEU, for pointing out that last error.



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