[GreenKeys] Wednesday Update on HoffNet

[Bob Camp]

Hi,

Ok, let's assume for an instant that we are swimming in equipment, 
cash, and antennas. Here's a proposal based on sunrise and sunset in 
Kansas City.

6 hours after sunrise to 6 hours before sunset: 			20 meters  then
up to 3 hours after and 3 hour before:				30 meters then
  before and after: 								40 meters then
3 hours before and 3 hours after: 					80 meters then

On an average day:

We're on 20 meters for 6 hours
We're on 30 meters for 6 hours
We're on 40 meters for 6 hours
We're on 80 meters for 6 hours

Around December we are on 20 meters for less time and 80 meters for 
more time. In June the opposite will be true. Since the country is 
about four solar hours wide we will be two hours before or after local 
sunrise we do the 40 meter switch. That's probably about as good as it 
gets when you do a fixed schedule like this.

Ok, how does it work.

Mostly what you are going to do is receive. If we do well defined 
frequencies then cheap fixed frequency receivers will do the trick 
pretty well. There is no real need to switch the receivers around 
during the day. The same thing is true with the antennas, in general 
you don't need a fancy antenna on receive. If we have a digital lock 
auto start then voting the outputs of the receivers is fairly easy. I 
would guess that the whole setup would be under $200 full up.

We are still compatible with older gear. If you have four receivers, 
TU's and TTY's all you wold have to have is a simple timer to 
enable/disable them. The only reason for doing so would be to cut down 
on the junk.

If you want to burp back an response to an sel call then things would 
get a bit more complex ....

On transmit, you only are going to be on one band at a time. Before you 
start up you check a schedule. Based on it you decide which band to 
fire up on. Setting the transmitter up on frequency is mostly a matter 
of having a dummy load and a counter handy. I would guess it adds about 
20 seconds to the process of setting up to transmit. Of course if you 
have four transmitters sitting around then you don't have to switch 
them around.

Now let's say that maybe not quite all of us are swimming in gear. 
Maybe I'm only set up on two out of the four bands. I let the world 
know which bands those are and if you want to get me then you know when 
and where to make a try. For that matter I may only respond to sel call 
on one band but listen on all of them.

Obviously you could go one band up or down at any one time and probably 
make a contact. You are unlikely to find both 80 meters and 20 meters 
open at the same time. You probably could make a one on one contact on 
a couple of bands at any one time. If we are all going to listen in 
then the band choice gets a bit more complex, thus the fixed schedule.

The net result is a little bit like four independent nets. You don't 
have to be a member of all of them. The schedule simply gives us a 
better chance of following along as the band conditions change during 
the day. If you are not on a specific band then you can't follow us. 
That's no worse than a single band net once the band closes. At best 
we'll get ten or twelve hours out of any one band on a normal day. If 
you want to get more than that then you need more than one band. With 
four bands you might get 20 hours of coverage but you are never going 
to get 24 hours of coverage with HF and a country wide set of stations 
transmitting and receiving.

Since there are more of us with limited equipment than with infinite 
budgets the question is weather multiple bands are worth the 
effort..... I don't see any basic reason why this wold not work or any 
real reason why it is any more complex than an individual wants it to 
be. If you want to run one band then go for it. If you want to run 
multiple bands then here's the way to do it.

	Take Care!

		Bob Camp
		KB8TQ




On May 12, 2004, at 11:30 PM, Roy Norris wrote:

> Today saw very little on the air activity.  Band conditions continued 
> to
> be poor.  George, W7TTY and I conducted some test this morning on 20
> meters, 30 meters, and on 40 meters.  I was inaudible in Auburn,
> Washington on all bands.
>
> I had a nice QSO on 20 meters with Bryan, W6QNE in Bethel Island,
> California (Southern) and he gave me an S-9 signal report.  I was also
> heard in Alaska by Tom, KA1NVZ
>
> These tests have been conducted on a 135 foot dipole at 65 feet, fed
> with open wire and tuned with a Johnson Matchbox.  Power on 20 meters
> and 30 meters was 150 watts.  Power on 40 meters was 60 watts due to
> high SWR.
>
> The problem in communicating with George in Auburn, Washington, was
> probably exacerbated by the fact that my dipole antenna runs NW - SE
> putting him off the end.
>
> I've drawn the following conclusions based on my tests.  30 meters (10
> Mhz) is probably out as a single net frequency due to propagation.  20
> Meters will allow us to cover the entire country but isn't open much
> before local noon and closes by 9:00 PM local time.  Forty meters opens
> a little earlier and closes a little later.
>
> My next course of action is to put up vertical dipoles for 20 and 40
> meters so that I will have general coverage of the US, unlike with the
> dipole.
>
> Secondly, I now have the Hal DS-3100 in house and I will put that on
> line to serve as a WRU until Gil finishes with the TTY-Connect project.
>
> Finally, I got my GPS time/frequency standard working and can now set
> transmit frequency to an accuracy of 1 part per billion !  So net
> frequency will be well within 1 cps accuracy.
>
> It will take me several days to get the new antenna up and the DS-3100
> set up.  I am going to use two wires tied to the same feed line, one 
> for
> 20 meters and one for 40 meters, for the verticals.  I plan to feed it
> with open wire line and tune it with a Johnson KW matchbox.  It will
> take me a little time to get this done so I probably won't be ready to
> begin testing again until Saturday.
>
> I am suggesting the following frequencies on the 20 meter and 40 meter
> bands:
>
> 20 Meters:  14.083300  and  40 meters:  7.083300
>
> On 30 Meters, our old standby:  10.137300
>
> Please let me know if anyone wishes to suggest other/alternate
> frequencies.  But based on our earlier discussion, it seems like these
> would work for everyone.
>
> Once again, I plan to start testing again on Saturday.  I will publish 
> a
> schedule later.  If we still have trouble, I will boost power from 150
> to 1500 watts.
>
> Its looking like the best approach is going to be a multiple frequency
> approach as suggested by Bob Camp earlier.  Perhaps 40 meters, 30
> meters, and 20 meters along with some sort of schedule for what to use
> when .
>
> Comments are welcomed .
>
> Best regards -- Roy Norris, K4EEG
>
>
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