[Premium-Rx] WJ-340A manual / CEI-357

[ToddRoberts2001 at aol.com]

In a message dated 6/22/2007 8:42:31 AM Eastern Standard Time, 
ka5qep at sbcglobal.net writes:
I don't think you'll find much similarity between the 340A and 357 WJ 
receivers.  The 357 is tuned with an air variable capacitor and the 340A 
with a voltage variable capacitor diode. As far as the stability of the 340A 
I found it poor compared to the 357.

John Reed 
 
 
Hi John,
       I have found quirks in the tuning and handling of the CEI-357 also. I 
think I remember that as soon as you switch to any mode that uses the BFO 
including USB/LSB you are forced to use MGC. The variable BFO setting seems to be 
easily pulled by the gain setting so when you crank up the IF gain on a signal 
the BFO pitch changes. 
       The fixed crystal-controlled BFO pitch is either 0 or 5.5KHz which is 
not too practical for listening to a CW signal by ear. I fixed the variable 
BFO problem by installing another BFO crystal with a 500Hz offset in place of 
the 5.5KHz crystal - that gives a nice stable 500Hz CW offset. 
       Another quirk in the tuning is they use a somewhat high offset for 
USB/LSB which makes the audio sound shrill and there is no offset in the freq 
readout, so when you switch to USB/LSB the freq readout stays the same and you 
have to mentally add or subtract an odd figure to get the real frequency you are 
listening to. A solution I am planning to try is to replace the USB/LSB 
crystals with 1KHz offset crystals. That way you can just mentally add or subtract 
1KHz from the freq readout to get your actual frequency when in SSB mode.
       One other improvement I would like to try is to rewire the mode switch 
so the receiver will stay in AGC mode in all other reception modes. This 
would fix the constant fiddling one has to do with the IF gain control when tuning 
in the CW or SSB modes to prevent overload on stronger signals when you are 
forced to use MGC.
       Other than those quirks the CEI-357 is a good receiver and very stable 
in the DAFC mode.
 
       73 Todd WD4NGG



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