Volume 29, Number 7 - JULY 1999
Kurt Kiesow, KF6QNC will speak on APRS.
We had a speaker on this topic a while ago, but it is time for a refresher.
It works like this: Take one ham and attach him to a Geopositioning device,
computer and a transceiver. Send the ham out running around in circles.
Track the ham by way of the Internet and APRS software which displays the
location of the ham on a map on your very own computer.
APRS WEB Sites:
- Download site for APRS info and Software.
The following web site is used to track someone with APRS where you know
their callsign, like Andy Fu, AC6GN or Chris Verbil, N5CV.
(where callsign is the callsign of the person you want to track)
Information source: Howard, KE6PWH
WILKES LATE WITH NEWSLETTER AGAIN
Sorry about that, I got my weeks mixed up. If I hadn't run into
Arv at Haltek, this newsletter would have come out next week.
Field Day was a success after a lot of hard work by the few who participated.
We were sadly lacking in operators and loggers.
The new transceiver has been installed at the club station and we encourage
club members to get checked out and operate the station.
We are going to be operating the club station in some of the other contests
and the purpose of this is to train club members in the operation procedures
during contests. This will give you a chance to operate the club
station and to learn about contesting.
It is time for club members to start thinking about who you want as
officers for next year. We always come up to election time and have
a difficult time finding those who are willing to help lead the club.
Some members have served and served and really have done more than their
share and it is time that those of you who haven't served to be willing
to lend a hand.
Livermore Swap Meet - 1st Sunday of each month at Las Positas
College in Livermore, 7:00 AM to noon, all year. Talk in 147.045 from the
west, 145.35 from the east. Contact Noel Anklam, KC6QZK, (510) 447-3857
Foothill Flea Market - 2nd Saturday of each month from March
to October at Foothill College, Los Altos Hills. FARS NET on 145.23 repeater
Thursday nights at 8 PM.
Jim, WE6V is running W1AW code practice sessions on the 145.23 repeater
every Tuesday evening 8:00 to 8:30.
APPARENT S-METER ANOMALIES
The 145.230 repeater S-Meter has generated a lot of interest and controversy.
I recently heard some interesting S-meter reports. One person who was testing
first got an S5 reading then on the next test he got S9. This is
an apparent 4 S unit change. As each S unit is 6 dB, that would seem
to be a 24 dB increase in power entering the repeater receiver. If
one were using a 2.5 watt HT, 24 dB up would mean the person was running
an amplifier with 628 watts out. While this IS possible, it is not
There are several other possible explanations. Remember that while
the repeater's S-meter is calibrated to respond to an analog input, the
controller's output is digital. One can envision this as a set of
stairs going up, each step of which is 6 dB (one S unit). Superimposed
on this stairway is a smooth curve of the analog signal. Ideally,
the analog signal will touch the stairs at the corner of each step.
If the initial S5 reading were near the top of one step, say only 1/2 dB
below, and the S9 were just above (say 1/2 dB above) the S9 stair step,
then instead of a 24 dB increase, there would really be only a 13 dB (two
steps at 6 dB each plus two 1/2 dB steps) change. 13 dB above 2.5
watts is ~= 49.9 watts. 50 Watt amplifiers are a lot more common
on two-meters than 628 Watt amplifiers.
One other logical explanation assumes that the S5 was obtained with
an HT putting out only 200 milliWatts. Some of the new shirt-pocket
HTs have the capability to select a very low power output. One 523
repeater user puts out only 50 mW into a good antenna which results in
an almost complete quieting of the repeater receiver. Assuming a
true 24 dB change, 24 dB above 200 mW is ~ = 50 Watts which is well within
the normal range of many amplifiers.
Heard on the repeater recently, a mobile station at rest was testing
using the S-meter. This station said that they varied the power setting
on his radio from 5 Watts to 50 Watts and the S-meter gave the identical
reading at both extremes and at several levels in between. His conclusion:
"I guess the S-meter isn't working". What might have been happening there?
OK, one could say that the S-meter was not working, but that response was
thrown out by other stations testing and obtaining reasonable reports.
There are several other possibilities, however. Just because one switches
a radio from low to medium to high power does not mean that the radio is
in fact changing power levels. I remember checking one HT which had multiple
power settings with a through-line wattmeter connected to a good dummy
load. Changing the power level switch had NO effect on power output Conclusion:
the Power Level switch on the HT was not working.
In a mobile installation there are other possibilities. With the engine
off, a weak car battery will experience voltage drop as more current is
taken from the battery. In this scenario, with the radio in the low power
position, the battery voltage may be 12 volts. At the 50 Watt position,
the 10 Amps or so drawn by the radio to put out that amount of power could
cause a weak battery to output only 10.5 to 11 volts. Thus the radio is
not really putting out 50 Watts even when the switch is in the 50 Watt
A similar situation would exist if the car motor were running and a
new car battery were installed, but the connection to the to the battery
were though the cigarette lighter and/or there were even a small resistance
contact somewhere between the battery and the DC going into the radio.
At a current of 10 Amps, it would take only 0.1 Ohm resistance to drop
one volt between the battery and the rig. Yet this could significantly
affect the rig's power output.
Keeping in mind the stair-step analogy above, switching from 5 Watts
to 50 Watts should yield a 10 dB gain in signal strength, or one and two-thirds
S units. But the controller does not report in thirds of an S unit. The
signal has to at least be at or over the next step to read the next S unit.
So, if everything were working properly, a change from 5 to 50 Watts output
should cause a 1 S unit change in reading. How far would power have to
drop not to hear any change? If we assume that at 5 Watts output, the signal
at the repeater was just barely above the S5 level, the signal could rise
5.5 dB and still not read an S6. 5.5 dB above 5 watts is: 17.74 Watts.
(17.74 / 5 = 3.548 and 10 x log 3.548 = 5.5 dB).
There are other possible causes of apparent S-meter anomalies. Some
examples: if one were using an HT to drive an amplifier and both were being
powered from the cigarette lighter outlet, if the current taken by the
amplifier were causing the voltage to the amplifier to be low, the voltage
to the HT would also be low. Even if the HT is operating on internal batteries,
how well is the internal battery holding up (over the duration of the test)
at 5 Watts out of the HT? If one is using an HT to drive a Class C amplifier,
but the HT is on low power, there may not be sufficient drive to the amplifier
to have it produce full output.
So what is the answer? For starters, IF the S-meter is not responding
the way you expect, monitor the voltage actually going into the back of
your rig, whether at home or in the car. (Beware of possible RF effects
on any voltmeter using semiconductors. One may have to use an analog meter
in series with an appropriate resistor to obtain an accurate reading in
the presence of RF.) As we have seen above, even a small resistance somewhere
between the power source and your radio could be the problem. Second, attach
a power meter at the output of your rig and measure actual change in power
output as the power level switch is changed for one level to the next.
Chances are that if the S-meter is not changing S unit levels, that the
rig is not putting out enough power to cause it to change.
De Rich, W6APZ
I did an Internet search for newsletter input and was pleased to
find the above by one of our very own was the most interesting this month.
Amateur Radio Newsline
Proposed APRS Satellite Some of the nations APRS leaders have been doing
conceptual studies for a small nano satellite for relaying APRS status
position packets from stations in remote areas and off shore. This, according
to an internet posting by the father of the mode Bob Bruninga, WB4APR.
According to Bruninga the biggest problem has been designing the system
to be optimize for mobiles while mitigating the interfering signals from
all the fixed operations on a given radio channel. But says WB4APR the
job is not as difficult as first thought. This is because 90% of the North
American population located on 20% of the land is already covered by the
APRS infrastructure. This means that a dedicated APRS satellite need only
supply coverage in the remote 80% land mass. This is because the remote
80% comprises only 10% of the population. This means interference is minimal
where satellite relay is needed the most as the remote mobile will be hearing
nothing else on the channel since he is far from any other stations. This
means an almost 100% chance at hearing the downlink. Bob says that this
makes a flying simplex digipeater operating a perfectly viable space satellite
application for North America and surrounding off-shore areas. The satellite
would be silent over the rest of the world if its operating frequency is
not available in order to abide by international agreements. No firm plans
for an APRS satellite are in place. It's only in the very beginnings of
a discussion phase.
(AMSAT BBS, VHF Reflector)
Kids Day Follow Up The June 19h Kids Day operating event was a bigger
success than anyone might have imagined. Hams around the nation heeded
the call and gave many of the nations youngsters their first look at the
magic world of Amateur Radio. And the world was listening in as we learn
from Australia's Graham Kemp, VK4BB: Kids Day on June the 19th showed off
Ham Radio to the next generation. Kids Day was started by Larry Tyree,
N6TR under the auspices of the Boring Amateur Radio Club in Oregon. During
a January running of Kids Day more 400 youngsters took part at a fun on
the air event that has grown tremendously popular in the last few years.
Much like JOTA, but open to all kids. World Radio editor Rick Mc Cusker,
WF6O of Sacramento, California printed brochures about Kids Day and distributed
them in his neighborhood. He then threw a barbeque to feed the kids when
they stopped by to make some QSO's. And Rick Painter of Tennessee had a
similar notion. He invited a church youth group for pizza, soda and ice
cream, plus a chance to step up to the golden microphone at the Kids Day
Radio Party. This was the last Kids Day of the 20th century. The next one
is not that far away. It's slated for January, 2000.
DX In DX, 6 meters continues to conjure up images of 20 meters on
that bands very best DX days. For example, Ed Rodigez, WP4O in Puerto Rico
reports that he now contacts Europeans on a regular basis. Some of the
stations Ed worked on June 16th include G0JHC, EI5FK, F5JK and ON4ST. Ed
says that he worked all of these and more running CW to a four element
quad antenna up only fourteen feet. (VHF REflector) And even one of the
Newsline staff is getting into the 6 meter DX craze. On Monday, June 14th,
our producer Bill Pasternak was at work where they had just connected a
newly installed 5 element Cushcraft 6 meter beam to the stations Kenwood
TS 570 S transceiver. Bill gave a call on 50.125 MHZ and immediately made
contact with N2ODU who gave his location as being about 50 miles South
of Buffalo, New York. This took place at about 02:00 UTC with signals at
5 by 9 plus on two way SSB. (Newsline) So if we may editorialize to all
the Technician and Technician Plus class hams sitting on repeaters and
hoping that some day restructuring of Amateur Radio will permit them to
chase DX on the high frequency bands. The DX is already there for you on
6 meters. Your current Tech license, a 6 meter radio and an antenna is
all you need to bring that very special DX to you.That OTTER Radio Hunt
And finally, we all know that here in the United States hidden transmitter
hunts are often called Fox Hunts or even Bunny Hunts. But what about a
hidden transmitter hunt that takes place on water? According to John Arsay,
VK4QA, that's what the Dutch call an Otter Hunt. Here's John with more:
Today one should be in the Netherlands for an fascinating experienced as
VERON is organizing the fourteenth OTTER Hunt. We all know about fox hunts
or, to use its proper name, radio direction finding games. The Dutch, of
course, want to be different so they started the Otterhunt, It is held
near the old Zuyderzee, now called IJssel Lake, in a place called Meppel.
It is a pretty wet area and the fox, sorry, the otter can only be hunted
by boat'. The hunters can chase an Otter on two meters or on eighty meters
or, if 'they are really keen, can try to locate both otters, using two
receivers at the same time. Various boats are available for hire if you
don't own one yourself. These hire boats vary from a motorboat driven by
an electric motor to one man canoes but they don't say how many rescue
vessels there will be on the water! It will be a very busy period as one
has to locate not one, but five hidden transmitters, each transmitter point
having both a two meter and eighty meter unit. To make things morn interesting
or, should I say, more difficult, extra points will be awarded to those
hunters who manage to accurately indicate on their maps the location of
the found otters.' And to make things more interesting again, a questionnaire
must be completed covering the natural habitats of the area around the
Otters! If you think that the Otter Hunt is different, how about a T-Hunt
in the air. The Dutch are doing that too. That story, next week.
The Amateur Radio Newsline web page is at: www.arnewsline.org.
According to our Support Fund Administrator, Andy Jarema, Newsline has
received only enough financial support to keep the service going though
mid July. In other words, the bills from May have been paid, but now money
has to be raised to keep from losing the phones and e-mail service in mid
summer. We also need to raise an additional $1500 to cover our part of
the expenses involved in administering and presenting the annual Young
Ham of the Year Award.
This was our site. The HF antenna is in the middle with the VHF antenna
on top. The VHF station was in the screened canopy on the right. Behind
the canopy was the truck with the HF station. The CW station and picnic
area were across the field in the left background and the RTTY station
was over the hill behind the CW station.
Some people worked very hard to make contacts. Virginia and her husband
came down from Oregon just for Field Day.
So did some others (Note: Get placement fee from 7-UP). Here are Dennis
and Charley at the Novice/Tech station. Goal for next year: Get some Novice
CW operators. After going through the available voice contacts, there was
nothing left except CW.
But then some other people.......... Just kidding. These people and
others worked very hard to make Field Day a success.
Paul, Jack, Martin, and Arv take a break after erecting towers (To Hell
with the Telecommunications Act).
One of the Field Day activities I missed most was conversing with Father
Wence. We lost him since last Field Day and none of the Fathers came over
to talk with us. Father Wence was in China when the Japanese invaded during
WW II. Everyone has a period of history and that was part of mine. How
many other stories do the priests have?
14 Years Industry Experience
Individuals, Trusts, Retirement Plans
No-Load Mutual Funds
Personal Account Statements
Peter W. Johnson, Jr., PFP (KN6MO)
Registered Investment Advisor
Internet - Firewalls - E-Mail - UNIX
Bridging the gap - Your net <-> Internet
3251 Firth Way, San Jose, CA 95121
408-322-3741 - Fax: 408-532-9362
How to get to meetings:
(Visitors always welcome)
FARS meets at the Covington School District building,
201 Covington Road, Los Altos. Take the El Monte exit (The same exit as
for the Foothill Fleamarket) off of I-280 and go East on El Monte. Cross
Foothill Expressway and turn right at the next light on to Covington (Note
Saint William church on corner). Stay to your left as the road forks. Just
past the fork, turn left into the school parking lot. Walk through the
center hallway and turn right. The meeting room is the first door on the
left. Talk in on 145.23 or 145.27, negative offset, 100 PL.