[600MRG] modeling tutorial

[Kenneth G. Gordon]

On 7 Sep 2015 at 18:45, D.J.J. Ring, Jr. wrote:

> AL7N is a fellow with lots of 600m experience, he was one of the last WT
> operators at Alascom's WKR Nome Radio installation in the 1980s.
> 
> http://radiomarine.org/gallery/show?keyword=WKRIRT&panel=pab1_7
> 
> Nome Radio/WKR was once part of the US military "Washington-Alaska Military
> Cable and Telegraph System" (Affectionately referred to as "WAMCATS".

Gee...I had no idea. Ed and I have been friends for some time now. I cannot 
remember when he and I first got together. He has sent me photos of his 
home-brew equipment. He builds a lot of it, except, perhaps, his receivers.

> How long ago did his antenna system get upgraded?  He has had a very good to
> excellent signal on 14050.0 kHz for quite a long time.

Within the last year. Possibly a year ago. I can't remember at this point. After 
all I'm 73 now. :-)
 
> What is he running?

On 20, I think he is using some sort of fairly modern rig which will output 
about 50 watts. Ten-Tec, I think. I can go back through my e-mails from him 
to take a look if you wish. He has told me that he really cannot afford any 
really modern gear, and he doesn't like the way they operate anyway.

>  If he isn't using a beam pointed this way,

No. He isn't, unless he changed to that very recently. He has neither the 
room nor the support for such.

> I'm really
> impressed as I've called him without a schedule on that frequency he listens
> there and 3550, 7050 and 14050 like a coast station!

Yes. He monitors those frequencies 24/7/365. He has speakers in every 
room in his home which he feels should have one. I've even gotten him out 
of bed once. :-)

>  He came up and had a 589
> signal sometimes, mostly 56 to 579 which is a great signal into Massachusetts
> from Fairbanks where he now resides.

Yup. :-)

What he was using for an antenna before we got together was a sort of low 
Vee-Beam of his own design, fed with open-wire line. He was using some 
sort of resistors at the low ends to connect them to ground.

According to the (first) EZNEC models which were run for us by Mel Ferrer 
K6KBE, then (second) my own MMANA-GAL models, his antenna, at the 
frequencies he was using it, was losing most of its radiation into the ground. 
It really was a "worm-warmer". Even without the resistive terminations it was 
very inefficient.

After doing some more modeling, we advised him to build an open-wire-line 
fed inverted-Vee. On his small property, the legs were pretty short, about 33 
feet long each. We advised him to put it up as high as he could get it. I can't 
remember the height, but it really isn't very high.

His coupler, which he built, is excellent, and he can match the antenna to his 
rig on 80 through 10 meters, although it seems to work best on 20.

There are at least two folks in Washington and Oregon who routinely pass 
traffic from RN7 to him: W7GB, and W7IZ. Sometimes, K7BFL does also. He 
is RN7's Alaska liason station. GB and IZ have commented favorably on the 
results of his "new" antenna. It has made their job much easier.

He has also built a small rig using an 829B for 30 meters. I sent him some of 
the parts for it: the tube (NIB), a socket and  (I think) a power transformer.

He is one sharp cookie, and a very fine operator. His fist is just beautiful, and 
he can hear signals that are so weak that very few other ops could hear 
them, let alone take traffic like he does.

I only wish he lived on a piece of property with a bit more room and out of 
town. I also wish he had some better equipment. It would really be nice to 
have him on 600 meters.

He has always impressed me, and until you gave me the info above, I had 
no idea at all of his past history.

Thanks, DJ.

Ken W7EKB