In article ,
Irv Finkleman wrote:


I am not as concerned about a case of 'rf lip' as I am
about stray RF causing possible problems with the
neighbours on all sides of me, with all my electronic
toys such as computers, DVD players, the local
fire-alarm system and other such things. The last
thing I want to do is draw attention to the fact that I
am running a ham radio station from my suite until
I know I am not causing any problems.

Thusly, my goal is to provide myself with a first rate
RF ground system, entirely contained within my suite,
in order that I do not wake up at night with the fire
alarms set off and great numbers of disturbed
residents gathered around pointing at me and saying
'Ham! Ham! For Shame! For Shame!' and the Residents
Council having special meetings to decide how to deal
with me. They already think I'm crazy -- and I may be
somewhat, but I don't want to make matters worse!

So, having herein explained my rational, lets see what
help I can get in the way of producing the ideal indoor
low-cost non-radiating counterpoise radial system.

Irv,

Your goals are certainly valid.

As far as preventing RF from going where you don't want it to... the
main issue MJF is talking about here is "conducted" RF. The RF energy
on the "ground" side of your antenna connector is going to flow
outwards through every conductive path available to it, including the
"counterpoise" side of your antenna arrangement, and anything
connected directly or indirectly to your rig's chassis (e.g. to the
power supply and then onto the third "ground" wire in the household
mains). The amount of current flowing through each of these paths
will depend on the RF impedance of the path, with more current flowing
through paths of lower impedance.

So, what you want is (probably) to have one or more counterpoise wires
whose RF impedance is as low as practical, at the frequency in
question. These could be quarter-wave wires, or they could be shorter
or longer wires with an "active ground" (which is essentially a simple
"antenna tuner" on the ground side, with an adjustable reactance to
cancel out some of the reactance of a non-quarterwave wire).

You can also help keep RF "where it belongs" by adding common-mode
chokes to your rig power cables, thus increasing the RF impedance of
this path and helping reduce the amount of current which is conducted
back into the building ground.

Another approach which may help, is to consider using an end-fed
half-wave antenna, with a specifically-wound matching coil system.
These are (in principle at least) largely ground-independent... the
low-impedance side of the matching coil provides good RF paths for
both the "hot" and "ground" sides of the antenna connection, and when
properly adjusted they don't dump much RF into the rig ground or
counterpoise.

These techniques may not help much, if at all, with *radiated* RF
getting into places you don't want it. Even if you have an antenna
which is fully balanced, and completely isolated from the building
ground (e.g. battery powered), the "near field" RF from the antenna
can be coupled into the building wiring, and start causing
interference and "undesired operation". Unfortunately, a lot of
consumer and industrial electronic equipment these days is very
vulnerable to this... poor shielding/filtering. Speaker cables,
telephone and alarm wiring, etc. can all act as antennas.

Not much you can do about this except try to route your antenna and
counterpoise wires as far away from other wiring as possible, keep
your transmission power down, and try to transmit during times when
people are asleep.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Thanks for your reply Dave,

I'm learning a lot in a hurry, finding out that grounds can be just
as complex as antennas, and all about the interelationship between
the two.

I do have chokes on the power cord of my 12v supply and
also on the supply cord between the PS and the rig.

Your half wave suggestion is not immediately forthcoming
due to the physical limitations I face here however it is
on my list of possible future condierations.

As per a previous post I have recently come into a
treasure trove of inductors and capacitors -- variables
of every type and sixe. With all this at my disposalI
plan to fiddle about with tunable counterpoises,
artificial grounds, and combinations thereof.

At least I'm on the air again, but because I gave
all my gear away I've had to jump from old tube rigs
into a QRP world with a teensy Yaesu Ft-817 that it
appears will take some time to learn to operate with
all its menus, settings, and such. I have to get new
glasses and perhaps a magnifier too.

The saving grace here is QRP with which I hope
to get into as little trouble as possible.

I'm a pretty good tech, and have fixed up and modified
lots of stuff but now I'm going to have to do a lot of
learning in the wild world of wire antennas and grounds.

Thanks for your good suggestions, and for taking the
time to reply.

73

Irv VE6BP

"Dave Platt" wrote in message
...
In article ,
Irv Finkleman wrote:


I am not as concerned about a case of 'rf lip' as I am
about stray RF causing possible problems with the
neighbours on all sides of me, with all my electronic
toys such as computers, DVD players, the local
fire-alarm system and other such things. The last
thing I want to do is draw attention to the fact that I
am running a ham radio station from my suite until
I know I am not causing any problems.

Thusly, my goal is to provide myself with a first rate
RF ground system, entirely contained within my suite,
in order that I do not wake up at night with the fire
alarms set off and great numbers of disturbed
residents gathered around pointing at me and saying
'Ham! Ham! For Shame! For Shame!' and the Residents
Council having special meetings to decide how to deal
with me. They already think I'm crazy -- and I may be
somewhat, but I don't want to make matters worse!

So, having herein explained my rational, lets see what
help I can get in the way of producing the ideal indoor
low-cost non-radiating counterpoise radial system.

Irv,

Your goals are certainly valid.

As far as preventing RF from going where you don't want it to... the
main issue MJF is talking about here is "conducted" RF. The RF energy
on the "ground" side of your antenna connector is going to flow
outwards through every conductive path available to it, including the
"counterpoise" side of your antenna arrangement, and anything
connected directly or indirectly to your rig's chassis (e.g. to the
power supply and then onto the third "ground" wire in the household
mains). The amount of current flowing through each of these paths
will depend on the RF impedance of the path, with more current flowing
through paths of lower impedance.

So, what you want is (probably) to have one or more counterpoise wires
whose RF impedance is as low as practical, at the frequency in
question. These could be quarter-wave wires, or they could be shorter
or longer wires with an "active ground" (which is essentially a simple
"antenna tuner" on the ground side, with an adjustable reactance to
cancel out some of the reactance of a non-quarterwave wire).

You can also help keep RF "where it belongs" by adding common-mode
chokes to your rig power cables, thus increasing the RF impedance of
this path and helping reduce the amount of current which is conducted
back into the building ground.

Another approach which may help, is to consider using an end-fed
half-wave antenna, with a specifically-wound matching coil system.
These are (in principle at least) largely ground-independent... the
low-impedance side of the matching coil provides good RF paths for
both the "hot" and "ground" sides of the antenna connection, and when
properly adjusted they don't dump much RF into the rig ground or
counterpoise.

These techniques may not help much, if at all, with *radiated* RF
getting into places you don't want it. Even if you have an antenna
which is fully balanced, and completely isolated from the building
ground (e.g. battery powered), the "near field" RF from the antenna
can be coupled into the building wiring, and start causing
interference and "undesired operation". Unfortunately, a lot of
consumer and industrial electronic equipment these days is very
vulnerable to this... poor shielding/filtering. Speaker cables,
telephone and alarm wiring, etc. can all act as antennas.

Not much you can do about this except try to route your antenna and
counterpoise wires as far away from other wiring as possible, keep
your transmission power down, and try to transmit during times when
people are asleep.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

On Wed, 25 Apr 2012 19:55:47 -0600, "Irv Finkleman"
wrote:

At least I'm on the air again, but because I gave
all my gear away I've had to jump from old tube rigs
into a QRP world with a teensy Yaesu Ft-817 that it
appears will take some time to learn to operate with
all its menus, settings, and such. I have to get new
glasses and perhaps a magnifier too.

Light reading on the FT-817:
http://www.ka7oei.com/ft817pg.shtml

The saving grace here is QRP with which I hope
to get into as little trouble as possible.

As soon as the neighbors find out that you're a ham radio operator,
several things will happen.
1. You will immediatly be blamed for all manner of electronic
failures. Kitchen appliances, computer crashes, and prematurely dead
batteries will all become your fault.
2. Neighbors will assume that you fix things for free. Training the
neighbors to pay for your time will be a challenge.
3. The phone will ring at 2AM asking if you're on the air and causing
reception problems with OTA TV, cable TV, satellite TV, etc.

I'm a pretty good tech, and have fixed up and modified
lots of stuff but now I'm going to have to do a lot of
learning in the wild world of wire antennas and grounds.

My theory is that if it doesn't work on paper, it's not going to work
when you build it. There are plenty of "standard" antennas that
usually work the first time (if you follow instructions). However,
you seem to be interested in designing your own. Therefore, I suggest
you download the demo version of EZNEC, or the free 4NEC2, and proceed
to model your prospective antenna system. When the computah says that
you're close, then it's time to build it. An MFJ269 or similar
antenna analyzer is handy for verifying your calculations.

Hint: One of my ham friends moved into a CC&R (covenants, conditions
and restrictions) infested condo farm. No antennas of any kind. The
condo council had at least one member that was certain that property
values would decline if a ham was allowed to operate from the condo
farm. So, I leaned a 20ft aluminum extension ladder against the house
and ran a wire to the radio. It worke quite well with a tuner. The
ladder was left leaning against the condo for a bit less than a year
before the condo council discovered the ruse. There was a short
debate. The council decided that since it had been in operation for a
year without any complaints or detrimental effects, it could stay.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

"Jeff Liebermann" wrote in message
...


snip

I leaned a 20ft aluminum extension ladder against the house
and ran a wire to the radio. It worke quite well with a tuner. The
ladder was left leaning against the condo for a bit less than a year
before the condo council discovered the ruse. There was a short
debate. The council decided that since it had been in operation for a
year without any complaints or detrimental effects, it could stay.

--
Jeff Liebermann

That is _so_ funny, I just got done mentioning my ladder experience!

"Sal"
big grin

"Jeff Liebermann" wrote in message
...
On Wed, 25 Apr 2012 19:55:47 -0600, "Irv Finkleman"
wrote:

(assorted snips for brevity)


Light reading on the FT-817:
http://www.ka7oei.com/ft817pg.shtml

Already been there and a few other places too, but
thanks just the same. There are always new links popping
up and I try to keep up with them too!

As soon as the neighbors find out that you're a ham radio operator,
several things will happen.
1. You will immediatly be blamed for all manner of electronic
failures. Kitchen appliances, computer crashes, and prematurely dead
batteries will all become your fault.
2. Neighbors will assume that you fix things for free. Training the
neighbors to pay for your time will be a challenge.
3. The phone will ring at 2AM asking if you're on the air and causing
reception problems with OTA TV, cable TV, satellite TV, etc.

After mucho years on the air in mucho locations I can say I've been
there, done that! This is however, my first real experience using a
very limited antenna and QRP.


My theory is that if it doesn't work on paper, it's not going to work
when you build it. There are plenty of "standard" antennas that
usually work the first time (if you follow instructions). However,
you seem to be interested in designing your own. Therefore, I suggest
you download the demo version of EZNEC, or the free 4NEC2, and proceed
to model your prospective antenna system. When the computah says that
you're close, then it's time to build it. An MFJ269 or similar
antenna analyzer is handy for verifying your calculations.

I have an MFJ-259B -- couldn't live without it, and with all the
stuff I gave away this was the one thing that I just couldn't part with.



Hint: One of my ham friends moved into a CC&R (covenants, conditions
and restrictions) infested condo farm. No antennas of any kind. The
condo council had at least one member that was certain that property
values would decline if a ham was allowed to operate from the condo
farm. So, I leaned a 20ft aluminum extension ladder against the house
and ran a wire to the radio. It worke quite well with a tuner. The
ladder was left leaning against the condo for a bit less than a year
before the condo council discovered the ruse. There was a short
debate. The council decided that since it had been in operation for a
year without any complaints or detrimental effects, it could stay.

Good move! I've always maintained that if you give me any old
piece of metal almost anywhere, I'd find a way to load it and get
on the air! And I've done it time and time again. I did 26 years
in the navy and moved around a lot -- quick and simple antennas
were a must! I also helped a lot of chums who moved into
condos or rest homes get on the air using similar methods.

This case now though, is the first time I ever went into a place
that seemed impervious to signals. I've often operated from
indoors with no problem, and here, the first time I flashed up the
receiver, thought it had gone dead -- that's how bad it was. The
first thing I did was checked the protective diodes on the
antenna connector and as soon as I found them OK, opened
the window and strung a short wire outside -- then everything
was 5/9 plus!

As per another sailor many years ago said, 'I have not
yet begun to fight!'

Irv VE6BP

On Sun, 29 Apr 2012 16:24:52 -0600, "Irv Finkleman"
wrote:

I have an MFJ-259B -- couldn't live without it, and with all the
stuff I gave away this was the one thing that I just couldn't part with.

For when you transmit into it by accident...
http://802.11junk.com/jeffl/pics/2011-12-03-Storm/
The MJF-259B is similar to the MFJ-269B, except that it lacks the
440MHz section. It's a very handy instrument, but is rather fragile
in that the detector diodes are connected directly to the RF
connector. One blast of too much RF, too much static electricity, or
even too much DC, and the diodes go poof.

Good move! I've always maintained that if you give me any old
piece of metal almost anywhere, I'd find a way to load it and get
on the air!

There's also the rain gutters.

This case now though, is the first time I ever went into a place
that seemed impervious to signals. I've often operated from
indoors with no problem, and here, the first time I flashed up the
receiver, thought it had gone dead -- that's how bad it was. The
first thing I did was checked the protective diodes on the
antenna connector and as soon as I found them OK, opened
the window and strung a short wire outside -- then everything
was 5/9 plus!

Welcome to the joys of modern energy efficient construction. The
walls are full of aluminum foil backed insulation for both thermal and
acoustic insulation. The windows are coated with Low-E Titanium
Nitride IR reflective coatings (40 ohms per square), which also blocks
RF. The roofing material is carbon doped (instead of asbestos) which
absorbs RF. The foundation is concrete, which also absorbs RF.
Meanwhile, the proliferation of microprocessors, switching power
supplies, and BPL like devices, offers multiple sources of QRN. You
had it easy at previous locations.

As per another sailor many years ago said, 'I have not
yet begun to fight!'

Fighting is easy. It's negotiation that drives me nuts.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Welcome to the joys of modern energy efficient construction. The
walls are full of aluminum foil backed insulation for both thermal and
acoustic insulation. The windows are coated with Low-E Titanium
Nitride IR reflective coatings (40 ohms per square), which also blocks
RF. The roofing material is carbon doped (instead of asbestos) which
absorbs RF. The foundation is concrete, which also absorbs RF.
Meanwhile, the proliferation of microprocessors, switching power
supplies, and BPL like devices, offers multiple sources of QRN. You
had it easy at previous locations.

I kind of fell behind in my knowledge of modern constuction.
I lived in my house for 29-3/4 years and even though I did
a lot of renos, the infrastruction remained basically the same.
It is good though that they are getting smart on energy
efficient construction and other things -- hopefully we will
leave our kids and grandkids with a world pointed in the
right direction.


As per another sailor many years ago said, 'I have not
yet begun to fight!'

Fighting is easy. It's negotiation that drives me nuts.

I'm on the air but not sure just how well I am getting
out, I don't want to measure it, I don't even care to
know since it is a whole different matter on QRP.
The proof will be in the pudding -- I may have to
wait for good band conditions, but the only
valid means of measurement will be the number
of QSO's and bands I can work.

From those lovely boxes of variable caps and
assorted inductors (some roller-inductors) and
a cheap 2nd hand 50ua meter I am going to build
up an artificial ground which is about as simple
a circuit as one can get -- the L&C in series and
make a sniffer out of the meter and a diode!. I
should have it all going in the next day or two --
as soon as I can get a round tooit. Yes. I admit --
I'm a master of procrastination

Well, on with the further adventures of
getting on the air to the point of satisfaction.
Is that a lot, I ask?

Thanks on the tips re the MFJ diodes. I'm aware
of them and can test and change them if need be.
So far, so good! I guess it wouldn't hurt to have
some on hand -- it's pretty inevitable that with
the experimentation etc, that I'll be doing some
or all will get blown before you can say poof!

Do you think that if I were to ask the management
here If I could have an aluminum ladder outside my
second floor window -- just to easy my mind about
the dangers of fire, they might agree?

Irv VE6BP



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 29 Apr 2012 19:12:01 -0600, "Irv Finkleman"
wrote:

It is good though that they are getting smart on energy
efficient construction and other things -- hopefully we will
leave our kids and grandkids with a world pointed in the
right direction.

Yep. It's happening, but very slowly and painfully. Ecology is
expensive in the short term, but worth the cost and effort.
Unfortunately, I've seen some abuse of power precipitated in the name
of the environment. Like all good things, environmental correctness
does attract a few flies.

I'm on the air but not sure just how well I am getting
out, I don't want to measure it, I don't even care to
know since it is a whole different matter on QRP.

Oh rubbish. There are plenty of ways to test your setup that doesn't
involve calling CQ and getting a subjective signal report:
1. You can login to one of the remote radios or receivers on the
internet, tune to an empty frequency, and listen to yourself.
http://beta.remotehams.com
http://www.dxzone.com/catalog/Internet_and_Radio/Online_Receivers/
2. You can join one of the internet QRP clubs.
3. Weak Signal Propagation Reporter Network
http://wsprnet.org
4. Reverse Beacon Network:
http://www.reversebeacon.net
5. You can listen for beacons to check your receiver and antenna:
http://www.ac6v.com/beacons.htm
Our local radio club also has a remote HF station controllable over
the internet (using HRD) but it's only for club members.

From those lovely boxes of variable caps and
assorted inductors (some roller-inductors) and
a cheap 2nd hand 50ua meter I am going to build
up an artificial ground which is about as simple
a circuit as one can get -- the L&C in series and
make a sniffer out of the meter and a diode!.

All an artificial ground does is tune out the ground lead inductance
so that it's series resonant at the operating frequency. In effect,
you're building a counterpoise. You could user your MFJ-259B or a
grid dip meter to resonate the ground lead, and forget about the meter
and detector. However, if you must use a meter, I suggest a
thermocouple RF ammeter. Getting it to heat up the series resistor at
5 watts might be a challenge, but it can be done. Otherwise, it's a
current transfomer, ferrite core, diode detector, and 50ua meter.
http://www.w1tag.com/RFA.htm

I'm a master of procrastination

I have a PHD in procrastination. Never do today what you get someone
else to do for you tomorrow.

Is that a lot, I ask?

Yes, if you try to do it all at once.
No, if you take your time, grind the numbers, do a little planning,
and invite all your friends to help.

Thanks on the tips re the MFJ diodes. I'm aware
of them and can test and change them if need be.

I could only test the diodes after they were removed. The 50 ohm
resistors in the circuit prevented easy checking with an ohms guesser.

So far, so good! I guess it wouldn't hurt to have
some on hand -- it's pretty inevitable that with
the experimentation etc, that I'll be doing some
or all will get blown before you can say poof!

Yep. My experience is that certain users tend to blow up diodes no
matter what they do, while others don't have any problems. I'm sure
it's the user, not the analyzer. Possibly static build-up or
ungrounded antennas. Dunno.

I've been fairly lucky replacing all 4 diodes without needed to
calibrate the device. However, if you find the readings off after
replacement, see:
http://www.w8ji.com/mfj-259b_calibration.htm
The procedure took me 2 full days on an MFJ-269B. It went much
quicker after I read and followed the instructions.

Do you think that if I were to ask the management
here If I could have an aluminum ladder outside my
second floor window -- just to easy my mind about
the dangers of fire, they might agree?

No. Someone will probably try to steal the ladder. 20ft ladders are
not cheap. I ran two u-bolts through the ladder base, and permanently
attached the u-bolts to two foundation blocks with half a bag of
concrete mix in the hole. Various attempts were made to steal it, but
nobody got very far with 30 kg of buried excess weight attached. The
connecting antenna wire also acts as a capacitive alarm when the HF
radio is not being used. All this was only possible because each
condo had its own private back yard.

Another problem with a 2nd floor ladder is that you will be feeding
the ladder from the top, rather than from the bottom. That will
possibly work, but probably not as good as feeding the ladder from the
bottom.



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558