[Elecraft] Iambic mode A vs B?

[David A.Belsley]

Mike:
    This issue comes up with some regularity on this reflector.  Allow 
me to repeat a message I sent on this matter some time back:

Iambic modes A vs. B:

  The difference has to do with what happens after you release an iambic 
condition.  An iambic condition is where the dot and dash paddles are 
held simultaneously (i.e., squeezed).  You can approach the iambic 
condition two ways: dot first and dash first.  "Dot first" means you 
start with the dot paddle and follow immediately with the dash while 
holding the dot, so there is some time when they are held together.  
"Dash first" is the same when starting with the dash.  Most chips are 
designed so that one or the other of these conditions is always 
recognized (i.e., it is not possible to hit them at exactly the same 
time).  [Note: because of the way the K2 is designed to accommodate a 
straight key mode, it does recognize a truly simultaneous hit, which 
could sometimes cause problems.  If, however, you are not using the 
straight key mode, you can turn this feature off in one of the menus.]

  Both modes usually have what is called 'auto complete.'  That is, even 
if you release the iambic condition before it is complete, it will not 
just stop where you let up, but will continue to finish off the 
character. Thus, in iambic A mode, if you start with a dash, hit the 
dot before the dash is complete (while still holding the dash -- that 
makes the iambic condition), and then release both paddles before the 
initial dash is finished, the keyer will nevertheless complete the dash 
and send the dot, thus sending the letter N.  Likewise, if you start 
with a dot, hit dash (without releasing the dot), then release both, 
the keyer will send a complete dot and dash, thus sending the letter A.

  Iambic mode B differs from the foregoing in that, under exactly the 
same conditions as above it will add an element to the character that 
is opposite the last element.  Thus, under the conditions described 
above for the letter N, since the last element was a dot (you started 
with a dash), a dash will be added to produce dash dot dash, i.e., the 
letter K.  And under the conditions described above for the letter A, a 
dot will be added to produce dot dash dot, i.e., the letter R.  Thus, 
in iambic B mode, an element is actually added to the character that 
was never explicitly sent. A single squeeze starting with the dot will 
produce R and a single squeeze starting with the dash will produce K.  
To produce N in this mode, you start with the dash, but then you must 
lift the dash paddle before hitting the dot.  This does not mean you 
must wait for the dash to complete before hitting the dot, just that 
you must not allow the dot to hit while the dash paddle is still down.  
If you hit the dash, let up and hit the dot all before the dash is 
complete, the 'auto complete' feature will in fact produce a perfect N. 
  The K will not be sent because an iambic condition was never 
established in this sequence of events.

  Some find the "addition" feature of B mode to be disconcerting.  
Others find is a real benefit.  I, personally, began with A mode on a 
CMOS III keyer, which is very good.  I found it very difficult, 
however, to grow accustomed to the A mode on the K2 keyer, and, 
strangely, found it much easier to master the K2's B mode.  Now it is 
by far my favorite keyer. It's your call.  I would simply try them each 
for a short while, get a quick idea which has the greater promise for 
your style of sending, and then stick with your pick (either one).  You 
will eventually learn it fb.

best wishes,

dave belsley, w1euy


On Apr 26, 2005, at 9:20 AM, Mike Markowski wrote:

> Can someone point me to a web page or enlighten me as to what are 
> iambic
> modes A and B, as shown on the K2 menus?  A google search brings up
> keyers, but I haven't found a page with definitions yet.  Contrary to
> what the K2 manual says, I find the timing on mode A to be much tighter
> than mode B.  In mode A, when I try to put out a letter 'C' I more 
> often
> send either CT or K.  Mode B seems easier, probably because it has a
> feel much more like the Ten Tec keyer I've been used to prior to
> building my K2.  In any case I'm curious as to just what the different
> modes are.
>
> Thanks!
> Mike  AB3AP
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