SX-28 Crystal Filter Alignment

Lin Robertson digital-conjurers at ROADRUNNER.COM
Fri Dec 12 23:41:01 EST 2008

Am in the process of doing a full alignment on a SX-28 via the instructions 
on BAMA by N6PY (SK), which he wrote to eliminate some confusion in the 
SX-28 manual instructions, which are none too good; unfortunately, 
paragraph one of Step 3 seems a bit confusing _itself_, and I was wondering 
if someone could clear this up:


"Switch to the crystal wide selectivity switch position. Turn off the 
modulation of the signal generator but leave its output level set to the 
crystal's frequency you found in Step 2 to get around a -5V reading. Turn 
the receiver's audio to hear some hiss in the receiver. (Here it comes.) 
Keep the phasing set for maximum selectivity _in crystal filter sharp_."


Uh, is it just me, or does the last sentence contradict the first 
sentence?  I mean, first it tells you to set to xtal wide, then it tells 
you to KEEP the selectivity switch in SHARP, as if it were already there. 
(??)  Which is correct?

[I tell you, I've been aligning HF RX since 1968, and this 28 Xtal Filter 
procedure (both) is driving me bonkers. I did a SX-28 once 20 years ago, 
and I think the memory of it was so bad I think I blanked it from my 
mind.  The HQ-180A procedure is a marvel of clarity compared to it.]

In any case, if anyone can throw some light on this, it would be MOST 
appreciated.  It's probably very simple, and I just probably developed a 
mental blind spot from dwelling on this for so long.

Many Thanks to the group in advance,


This list is a public service of the City of Tempe, Arizona

Subscription control -
Archives -

More information about the Boatanchors mailing list