[Elecraft] Re: radios on networks

[Brian Lloyd]

On Jun 5, 2007, at 9:33 AM, Doug Faunt N6TQS +1-510-655-8604 wrote:

>    From: Brian Lloyd <brian-wb6rqn at lloyd.com>
>    Date: Tue, 5 Jun 2007 08:36:11 -0700
>
>    I would love to have a universal interface that would plug into the
>    ethernet and let me sample and control things in my shack. I  
> want to
>    control my antenna switch. If I am doing weak-signal microwave  
> stuff
>    I need to coordinate the sequencing of my IF radio, my transverter,
>    my preamp and power amp switching, etc. Lots going on. I might want
>    to let the DSP in the radio perform the low-level modulation and
>    demodulation while letting my computer perform more of the high- 
> level
>    protocol functions.
>
> We're getting pretty close to that with USB now,

The problem is, USB is a bad choice in this situation. It is a short- 
range master-slave system. It is intended to have a single master  
controller control a few attached devices. That works for peripherals  
on your PC but it is not general purpose for our shack. We really  
want something that is peer-to-peer and has no limitations. There may  
be times when I want several devices on the network controlling  
several other devices. I might have two computers, three radios, two  
antenna controllers, a couple of amplifiers, etc. The system should  
not place arbitrary limits on what I might dream up.

> and I suspect Ethernet equivalents aren't that far away.

That would be good.

> Of course, some people are
> going to want Bluetooth instead (which might happen first).

The key is to be able to run higher-layer protocols over it.  
Bluetooth can do that better than USB can but WiFi is an even better  
choice. Still, I would much rather have wire, especially in a shack.  
Less radiation to deal with. With 100Mbps ethernet each cable can run  
100Mbps. The more connections I make, the more capacity I have (using  
switched ethernet). With WiFi and Bluetooth all my devices have to  
share the same capacity and they are subject to RFI, something not  
all that unusual in a shack. And if the ham is trying to "work the  
bird" or do EME on 2.3GHz, they are NOT going to want WiFi and  
Bluetooth cruft floating around causing interference.

> But given
> the state of flux of the world, I think Elecraft has made a good, if
> conservative, decision.

Given the cost of serial and the cost of Ethernet I would tend to  
disagree. Other than perhaps some backward compatibility there is no  
real advantage to serial RS-232 over Ethernet and a lot of  
disadvantages.

> It might even be practical to add an Ethernet
> to serial interface internally.

No, that would be a bad decision as it would not make anything any  
better. Ethernet provides multiplexing already. Serial does not.  
Ethernet provides 1000 Mbps. Serial does not. I could go on and on.  
Ethernet-to-serial is just a band-aid. Better to put the ethernet  
controller right on the processor's bus where it belongs then you  
have all the features of Ethernet. And you can still emulate a serial  
interface if you really want to.

> I've done a trivial mod to add
> internal USB to a Z90, and it certainly looks possible to add internal
> Ethernet to that unit.  But that takes software and perhaps some
> administration.

Yes, and this is not a bad thing. (More below.)

> I note that my printer is connected by Ethernet, but required a  
> driver for that.

That is because most printer manufacturers try to move the processing  
into the computer rather than putting the printer processing in the  
printer where it belongs. This is a poor engineering decision based  
on reducing costs. You will find that good printers use a standard  
protocol on the wire and do all the processing local to the printer.

And yes, it takes software. When doing something it takes effort to  
do the the right way the first time and doing it the right way is  
probably not the easy way. OTOH, once you have done it the right way  
it pays big dividends in the long run as you can build great things  
on a common base.

If you want a perfect example, look at the Internet. When we were  
designing the protocols for the Internet we tried to make things as  
simple, general, and expandable as possible so that we could make new  
things in the future as we thought of them. Look at all the cool  
things that have come from that sort of thinking. It should be  
applied to our other communications systems as well.

>
> In the meantime, look at what N8LP has done.
>
> 73, doug
>

73 de Brian, WB6RQN
Brian Lloyd - brian HYPHEN wb6rqn AT lloyd DOT com