[NLRS] Use of Light in VHF Contests

[Mike KBØozn]

Hi all,
I hope I don't sound too naive about all of this having not used this 
mode for any qso's as of yet, but it sounds like the rules on a low 
level are set up so that one is not allowed to use a plain old light 
source, like a flashlight for instance, to simply point it at the fellow 
you are trying to make a contact with and simply switch it on and off in 
a cw fashion to make the contact.
But instead, one is required to use the light source like one would a 
radio.
At the time these rules were made I would guess that lasers were  more 
or less the obvious choice for a light source.  These days, there are 
many choices for solid state light emitting devices, LED's, Luxeons 
(name brand bright LED), and lasers to mention some common ones.  I 
wouldn't eliminate gas laser tubes either, nor other light emitting 
technology for that matter.
Personally I don't see any problem with using any of these safely to 
make the contact, again, as long as there is at least one stage of 
electronic detection.
I've read about using cloud scatter for instance and that sounds pretty 
interesting, but I would guess that it wouldn't be even remotely 
coherent at that point even if it started out that way.

In short I would agree that whatever we do it should encourage 
experimentation done safely, not stifle it.  To that end, I think the 
rules should be as open as they can be.

As I reread this it does occur to me that one might simply modulate, 
perhaps with a switch (low speed) or a laptop (high speed) a flashlight 
(perhaps an LED one) and use a simple photo diode at the receive end 
tied into a sonalert, (low speed by ear decoding, aka cw), or laptop, 
(high speed decoding)
I'm not sure if I would like this (the low speed part at least), but I'm 
not sure how it could be precluded either since one could easily do this 
with a laser and thus have coherent light, as well.
Of course these are both digital modes and we could eliminate them by 
specifying no digital modes, but that would be pretty limiting these 
days and so I wouldn't be in favor of saying that.

Well, that's my 2¢ for now.

Mike
KB0ozn

David Palm wrote:
> 
> Those were some very interesting comments, Jon.  One question I have: what
> is the rationale for specifying a "coherent" light source at all?  We
> certainly don't specify that our radio sources must be coherent--far from
> it.  So why should there be some difference as we get to this high end of