[GreenKeys] WRU and SELCAL

[Roy Norris]

I would vote for three selcal options and a last 4 call letters WRU:

1. Copy everything that qualifies as a valid digital signal
2. Copy all bulletins
3. Copy messages for my station

These options would be switch selectable on a simple microcontroller
based  box and 100% compatible with the standard M28 stunt box for those
who want to implement selcal and/or WRU all mechanically.

Roy, K4EEG

-----Original Message-----
From: Bob Camp [mailto:ham@cq.nu] 
Sent: Tuesday, April 27, 2004 6:15 AM
To: rnorris@charter.net
Cc: eric@k3na.org; eric@k3na.org; greenkeys List
Subject: Re: [GreenKeys] WRU and SELCAL

Hi

There are two ends to the mechanical compatibility issue. One is on the 
sending end the other is on the receiving end. I agree totally with the 
idea that the receiving end needs to be mechanical compatible. On the 
sending end I guess I have always assumed that you would punch up a 
tape with what ever you need to fire things up on it. You could come up 
with some kind of mechanical robot to do it all but that sounds like a 
bit more work that it's worth. I don't remember any "real world" gear 
out there that did the send end of the setup without using a tape. Of 
course that may not mean a lot ....

If we go feature nuts on the sending end it just adds stuff to a tape. 
If we go feature nuts on the receiving end that fills up stunt boxes 
and it's a problem. I'm not really suggesting that we go feature nuts, 
only that we need to look at which end of the process is impacted by a 
given feature.

Here's an example: Maybe I'm into propagation forecasts. After a bit of 
yack it turns out that there are others who have the same interest. Up 
goes Bob's daily propagation forecast. I can send a long string of 
SELCAL's (one for each guy who wants a copy) -or- I can send it blind 
and you have to copy everything to get it -or- we can invent a unique 
SELCAL for the thing.

All three approaches work. The first one with a long chain of call 
signs is a pain to administer but it makes the receiving end of things 
easy. The second approach also works and it's very simple, it just uses 
a lot of paper. The third approach makes things like stunt boxes fill 
up with extra parts.

If everybody invents a new "bulletin" SELCAL then we need stunt boxes 
the size of a small car to keep up with everything.

In this case here's what I would suggest. Add a single feature - a 
bulletin SELCAL. That way you can reasonably decide to get the 
bulletins but not copy everything on the whole net. If we make it 
something simple it should still fit in a more or less normal stunt 
box. If we follow the bulletin SELCAL with a bulletin specific tag then 
people with fancy setups can get more selective about which bulletins 
to accept. In other words you keep the "feature" simple enough to work 
on the receiving end and add a little to the sending end to do give us 
full functionality.

I hope that makes some sort of sense. I'm not really going to get into 
the propagation  bulletin business but it is a reasonable example. 
Bulletins make good things for adjustment and test of setups. I think 
they are something we want to encourage. I also think we want to do it 
as simply as we can. I think we can come up with a pretty darn simple 
system that also is very flexible if we work it out in advance. Tearing 
into stunt boxes on a regular basis isn't a real good idea. There are 
only just so many selector bars left in the world ....

	Enjoy!

		Bob  Camp
		KB8TQ




On Apr 26, 2004, at 11:04 PM, <rnorris@charter.net> wrote:

> Hi Eric,
>
> Great suggetions !!!  I agree, we should maintain complete 
> comptability with  mechanial selcal and wru.
> Regards -- Roy, K4eeg