Re: Topband: Feedline Choke Placement in RX systems

[Adrian]

The feedline (if coax) outer braid responsible for imbalance RF 
radiation, is fed from the antenna end.


Choking it there eliminates a RF active length.


vk4tux

On 1/12/21 03:48, Dennis W0JX via Topband wrote:

K9YC made an interesting comment in his post, saying that the feedline chokes 
would be most effective if placed at the antenna end of the feedline.
W1FV's 9 circle YCCC array has them right at the controller.
The older K7TJR combiner utilized no feedline chokes. However, I believe that 
Lee's new design has built in common mode protection on the combiner circuit 
board.
So what is the best way? Is placement dependent upon the combiner design?
BTW, K3LR is using 2.4 in #31 toroids with at least 24 turns of RG-179 as 
feedline chokes in his 8 circle HiZ array and I believe that there are chokes 
on both ends of the antenna feedlines. Of course, K3LR operates in a high 
intensity, multi-transmitter environment and may need all that choking.
73 Dennis W0JX
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Re: Topband: Balloon Supported Vertical

[Adrian]

Here, for full size 90cm - 1m balloons it works out around $20 au helium 
per balloon, plus $2 balloon plus $5-10 average line loss.


So a night session is around $30 au in costs on average, and only when 
conditions are right, otherwise you are wasting your time and $.


The bigger the industrial bottle you can purchase the better the deal. 
Also you can negotiate price with the supplier, I cut my original


offer price nearly in half as well is 25% off my rental. Recommended 
retail compared to a trade customer pricing has big pricing difference.


In the USA you should be able to do it for $20 or less per balloon. Also 
using too big a balloon is wasting helium $ and increasing line break risk.


I use difference inflation levels for each band 630m biggest to 80m 
smallest. If I re-use balloons, i only use them on 80m , which is the 
smaller inflation.


A bigger balloon gets hit harder and creates much more line stress with 
sudden gusts. The advantage of using 3/4 w setups is if the break is at the


1/4w point (trees house etc) the impedance change to the amp is not so 
dramatic and the LDMOS amp in low survives the event on swr trip.


Watching the swr real-time on the SPE, and have a finger on the halt 
button has saved gear here. A sudden wind change and a 2nd story gutter 
contact can just


blow the line at the contact point during TX, and its start again, but 
the amp remains good.


As the line changes angle the swr changes with it, and with experience 
trouble can be avoided.


The lift force should just be in excess of the total line weight, less 
than 2:1.



vk4tux


On 9/11/21 08:32, Mark - N5OT wrote:
> we used a 4-5' - "rubber"  balloon. (could've been latex or 
something similar)


So did I.  A 4 foot diameter balloon has 33-ish cubic feet of volume.  
Looks like Helium is running about $2 a cubic foot = $66 per use?


Gad.  Too pricey for N5OT.

73 - Mark


On 11/8/2021 4:21 PM, Adrian wrote:
Also the disposable party balloon bottles are a waste of $ and would 
only inflate 2 to 3 of the balloons here.


Industrial gas supply is required to make it viable.

"

ABN 95 000 029 729
Riverside Corporate Park
10 Julius Ave, North Ryde NSW 2113
Tel: 131 262 www.boc.com
Email: cont...@boc.com
2nd June 2021
Dear Adrian Fewster,
BOC special offer on compressed gas for Adrian Fewster.
Thank you for your enquiry regarding the supply of gases and 
equipment from BOC Limited. Our customers
are assured of BOC's genuine commitment to providing premium gas 
products and services in addition to
ongoing technical support, and the convenience of our large national 
distribution network.
Pricing for products which are purchased by you but which are not 
listed in the special offer pricing table
below will be charged at BOC's standard or list prices for each such 
individual product as varied from time
to time unless otherwise agreed. The gas pricing for the products 
listed in the special offer pricing table
below will be varied in proportion to changes in BOC's standard 
prices for each individual product and the
rental pricing will vary in line with BOC's standard charges unless 
otherwise agreed. This does not apply to
prices for LPG, Refrigerant, Helium and Acetylene products which will 
vary in line with Supplier increases as

they are incurred.
All prices below are GST exclusive. Price may vary if purchased from 
a different BOC Gas & Gear or Gas

Agent.
Gas CodeDescriptionCylinder
Volume
Annual
Quantity
Delivered
Price**
Rental (per
day)##
124GBALLOON GAS G SIZE7.1m31$398.31$0.6822
For refrigerant products a refrigerant reclaim and fluoro activity 
levy of $2.38/kg also applies.

** Where a standard local delivery option is available
## Rental Pricing is described as Service Charges in BOC's General 
Terms and Conditions of Supply

Rental Pricing
Cylinder CodeRental (per day)
'G' Size$0.6822
You may accept the special offer pricing above in the manner set out 
in the last paragraph of this letter. By
accepting the special offer pricing above, you warrant that you do 
not have a binding exclusive supply
arrangement with another supplier for any or all of the products 
listed in the special offer pricing table
above (or for products substantially similar to those listed) 
applicable to your site(s) where the products are

to be used.
The Agreement so formed between BOC and you for the supply of the 
products listed in the special offer
pricing table above will consist of the terms and conditions set out 
in this special offer pricing letter
together with the BOC General Terms and Conditions of Supply. (as 
amended from time to time) (accessible

from our website (www.boc.com.au)).
Under this Agreement we will supply and you will purchase all of your 
requirements for the products
covered by this Agreement. This Agreement will commence on the date 
of formal acceptance and continues
until you or we terminate it by giving a minimum of 6 (six) months' 
notice expiring at the end

Re: Topband: Balloon Supported Vertical

[Adrian]

Also the disposable party balloon bottles are a waste of $ and would 
only inflate 2 to 3 of the balloons here.


Industrial gas supply is required to make it viable.

"

ABN 95 000 029 729
Riverside Corporate Park
10 Julius Ave, North Ryde NSW 2113
Tel: 131 262 www.boc.com
Email: cont...@boc.com
2nd June 2021
Dear Adrian Fewster,
BOC special offer on compressed gas for Adrian Fewster.
Thank you for your enquiry regarding the supply of gases and equipment 
from BOC Limited. Our customers
are assured of BOC's genuine commitment to providing premium gas 
products and services in addition to
ongoing technical support, and the convenience of our large national 
distribution network.
Pricing for products which are purchased by you but which are not listed 
in the special offer pricing table
below will be charged at BOC's standard or list prices for each such 
individual product as varied from time
to time unless otherwise agreed. The gas pricing for the products listed 
in the special offer pricing table
below will be varied in proportion to changes in BOC's standard prices 
for each individual product and the
rental pricing will vary in line with BOC's standard charges unless 
otherwise agreed. This does not apply to
prices for LPG, Refrigerant, Helium and Acetylene products which will 
vary in line with Supplier increases as

they are incurred.
All prices below are GST exclusive. Price may vary if purchased from a 
different BOC Gas & Gear or Gas

Agent.
Gas CodeDescriptionCylinder
Volume
Annual
Quantity
Delivered
Price**
Rental (per
day)##
124GBALLOON GAS G SIZE7.1m31$398.31$0.6822
For refrigerant products a refrigerant reclaim and fluoro activity levy 
of $2.38/kg also applies.

** Where a standard local delivery option is available
## Rental Pricing is described as Service Charges in BOC's General Terms 
and Conditions of Supply

Rental Pricing
Cylinder CodeRental (per day)
'G' Size$0.6822
You may accept the special offer pricing above in the manner set out in 
the last paragraph of this letter. By
accepting the special offer pricing above, you warrant that you do not 
have a binding exclusive supply
arrangement with another supplier for any or all of the products listed 
in the special offer pricing table
above (or for products substantially similar to those listed) applicable 
to your site(s) where the products are

to be used.
The Agreement so formed between BOC and you for the supply of the 
products listed in the special offer
pricing table above will consist of the terms and conditions set out in 
this special offer pricing letter
together with the BOC General Terms and Conditions of Supply. (as 
amended from time to time) (accessible

from our website (www.boc.com.au)).
Under this Agreement we will supply and you will purchase all of your 
requirements for the products
covered by this Agreement. This Agreement will commence on the date of 
formal acceptance and continues
until you or we terminate it by giving a minimum of 6 (six) months' 
notice expiring at the end of the
minimum period of 1year(s) or by either party giving a minimum of 1 
(one) months' notice after the expiry
of the minimum period, or until it is terminated under the BOC General 
Terms and Conditions of Supply.
At BOC we believe that our business is here to help your business so if 
you have any queries please feel

free to get in touch with me at jamie-lee.pale...@boc.com.
This offer will be loaded to your customer account within two business 
days. "



vk4tux


On 9/11/21 07:54, W7TMT - Patrick wrote:

Regarding the helium…

Be advised the gas used by the party stores these days is almost always a 
mixture and not pure helium. That’s means considerably less lift. You’ll likely 
need to source the good stuff from a industrial gas supplier.

W7TMT

From: Topband  on behalf of Mark - 
N5OT
Sent: Monday, November 8, 2021 1:17:53 PM
To: TopBand List
Subject: Re: Topband: Balloon Supported Vertical

Been There Done That

You might want to figure the weight of what you have to lift.  One would
think it was, like, duh, you make a wire vertical and fill a balloon
full of helium and ... but it turns out you need to be careful about the
weight of the wire and insulators and you need to project how much
helium you can use and how much lift you will need and ... all that.

Just saying all that because the last thing you want to find out is,
after you've got it all together, you just can't get it up in the air.

I seem to recall I needed more like a 3 or 4 foot balloon to lift mine.

And be careful of the sticker shock on the gas.  I thought it was a lot
of money 20 years ago.  Rumor has it, it has not gone down in price.

The first one worked well until I had a bad wind.

The second one had some kind of corona arc off the top of the wire which
popped the (relatively expensive) balloon after only a couple minutes of
testing it out.  Or something.  It popped on a clear calm day but under
Full 

Re: Topband: Balloon Supported Vertical

[Adrian]

Even here the industrial stuff is not 'pure' helium.

They don't admit this until questioned. Helium molecules being smaller

leak through the latex skin leaving the bigger air molecules trapped 
behind.


After the session, I usually bring the balloons back into the house and 
untie them after a few days for re-use,


but for a smaller 80m use size, as they deteriorate and often pop if 
re-reinflated to original size.


After 2-3 days on the ceiling and reducing to 1/3 -1/4 size they sink to 
the floor, indicating the residual gas is


not helium, otherwise it would still float. Some have said it is safety 
feature for people not to black out when breathing


the gas for the funny voice gag, Otherwise it is just paying for what 
you don't need, to be legally ripped off.




vk4tux


On 9/11/21 07:54, W7TMT - Patrick wrote:

Regarding the helium…

Be advised the gas used by the party stores these days is almost always a 
mixture and not pure helium. That’s means considerably less lift. You’ll likely 
need to source the good stuff from a industrial gas supplier.

W7TMT

From: Topband  on behalf of Mark - 
N5OT 
Sent: Monday, November 8, 2021 1:17:53 PM
To: TopBand List 
Subject: Re: Topband: Balloon Supported Vertical

Been There Done That

You might want to figure the weight of what you have to lift.  One would
think it was, like, duh, you make a wire vertical and fill a balloon
full of helium and ... but it turns out you need to be careful about the
weight of the wire and insulators and you need to project how much
helium you can use and how much lift you will need and ... all that.

Just saying all that because the last thing you want to find out is,
after you've got it all together, you just can't get it up in the air.

I seem to recall I needed more like a 3 or 4 foot balloon to lift mine.

And be careful of the sticker shock on the gas.  I thought it was a lot
of money 20 years ago.  Rumor has it, it has not gone down in price.

The first one worked well until I had a bad wind.

The second one had some kind of corona arc off the top of the wire which
popped the (relatively expensive) balloon after only a couple minutes of
testing it out.  Or something.  It popped on a clear calm day but under
Full Power.

Anyway, that wrecked my day.  I decided it wasn't fun any more and have
been using more conventional 160 meter verticals since.

I think we wrote it up in the NCJ but don't remember and have slept
since then.

Oh sorry, you asked where to get the balloons.  I think I got mine from
a party supply store.  It was not mylar.

Note - Googling reminds me of these facts:

Helium can lift 1 gram per litre.
A balloon 2 feet in diameter will contain 118 litres of helium.
That will lift 118 grams of antenna, = 4.1 ounces.
132 feet of bare #18 solid copper wire weighs 10.4 ounces.

A 2 foot balloon filled with helium will not lift a 160 vertical made of
#18 wire, not to mention any extra line or insulators, etc.

But a 4 foot balloon will lift a little over 2 pounds.

Now I'm having nightmares again.

73 - Mark N5OT


On 11/8/2021 2:48 PM, Dick Bingham wrote:

Greetings All

I want to try a balloon supported Vertical for 160.
Any advice on sources for balloons? Mylar material
and diameters up to 2-feet would be my choice.

73. Dick/w7wkr at CN97uj
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Re: Topband: Balloon Supported Vertical

[Adrian]

I have been doing it here for well over a year. I originally set it all 
up with a 1/4w vertical for 630m,


'which performs very well., Then also 160m and 80m using 3/4w lengths

For 160m I use 90cm latex balloons fully inflated. I use the online wind 
forecast showing area


wind velocity and direction. Over 7km/h it is a waste of time. A small 
wind velocity 5km/h and less is beneficial


if the direction is away from the target DX. It becomes directional back 
in from the line lean angle.


A slight breeze above 7km/h will bring the balloon down quickly, and 
getting snagged in trees with gusts is a common issue.


It is a game of luck as often the wind forecast is inaccurate, but when 
all is well it is unbeatable.


I use a G size industrial supply Helium bottle, for which I also pay 
rent monthly. It is still cheaper than a tower,


that would never get approval on a small block. As the activity is at 
night it is reasonably stealth.



vk4tux


On 9/11/21 06:48, Dick Bingham wrote:

Greetings All

I want to try a balloon supported Vertical for 160.
Any advice on sources for balloons? Mylar material
and diameters up to 2-feet would be my choice.

73. Dick/w7wkr at CN97uj
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Re: Topband: Amp tripping SWR ** progress**

[Adrian]

It doesn't need much swr increase to trip, A rise to 1.7:1 will do it 
despite that swr fine for use.


You did not comment on the SPE indicated swr. Can you see it rise just 
before it trips with gradual drive increase ?


vk4tux

On 30/10/21 10:59, WW3S wrote:
yep,, did thatdoesnt trip until somewhere between 300 and 400 
watts.and the alarm is instant.I suspect what is happening, 
based on my sons observation, and his recording the soundis RF is 
telling the relays on the switch to switch, and the 160 probably goes 
openI inserted a barrel connector and all is wellexcept on 
stuck on 160.tomorrow, in between other projects, I think we will 
swap out all the control cables


-

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Re: Topband: Amp tripping SWR ** progress**

[Adrian]

Sounds like you are still unsure, and that is a guess. You said the swr 
is 1.4:1 , I guess this what the SPE shows with SPE in standby, and txcr 
keyed ?


If so when switched to operate, you should be able to gradually increase 
drive power form a very low level and raise until you see the output power


level where SPE indicated swr suddenly increases and trips the amp? Or 
is the alarm instant regardless low low drive is in low power profile.


Test in FT8 in ssb is one good way to go from 0 output & up using audio 
level adjustment modulating the drive.


The SPE can be controlled from a few watts output smoothly through to 
the point where issues occur.


If the swr holds good until a output power level point where it fails, 
then it provides more clues to the problem.


An instant swr trip to standby regardless of drive level however low or 
0, is another issue.



vk4tux


On 30/10/21 09:54, WW3S wrote:

With the help of #1 son, during a lull in the monsoons, we isolated it to my 
KK1L 2x6 box, mounted on the outside of the house. Sounds like maybe some 
relays clicking and clacking, probably rfi coming thru the control cables, 
despite clamp on toroids everywhere and the cables wrapped numerous times thru 
double ferrite cores. I do have a couple of unused ports, I wonder if it will 
help if I terminate those with dummy loads?

Sent from my iPad
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Re: Topband: amp tripping on 160

[Adrian]

The amp is doing its job, and the swr trip threshold is 1.6:1. It is 
best to set the SPE atu toi bypass if used, and use an external


eg; Palstar manual tuner to tune the SPE display 1.10:1 or better on 
standby TX and in operate, adj the Tuner input/output capacitors for 
best under power,


leaving the roller inductor alone. After taking a 157m Helium balloon 
antenna off a 630m session last night ,


I was able  use it for 160m last night with the SPE / Palstar, with max 
400w using this method, with the SPE happy.


If I had removed 40m off the lower suspended antenna line (easy enough 
to do) I could have used USA power limits.


For a dedicated 160m antenna this treatment to allow the SPE to see a 
more favorable swr without trip will be good for 1kw +.


The SPE antenna programming for the output to the Palstar will be set 1b 
etc (b for bypass).


Again the tuner should be a manual like the AT2K, AT4K etc. Nothing to 
do with an unreliable amp, SPE are very swr sensitive for good reason.


In any case I advise using low power profile if you feel the antenna has 
a risk, as the LDMOS is much more likely to survive a sudden load 
impedance change.


Just need to know how to set it up to keep it happy, I have no doubt the 
nearby AM station would not be an issue with above procedure.




vk4tux


On 30/10/21 04:46, Ian Fugler wrote:

I'm afraid that I as soon as I saw the email header I guessed there would be 
mention of an Expert amp.  If you have the opportunity to borrow a more 
reliable amp and try that, I would be interested in your results, please.

73, Ian G4iiY



-Original Message-
From: Topband [mailto:topband-bounces+zen90387=zen.co...@contesting.com] On 
Behalf Of Jose_Carlos
Sent: 29 October 2021 16:17
To: WW3S; FZ Bruce
Cc: topband@contesting.com
Subject: Re: Topband: amp tripping on 160

My old friend  N8PR(SK) had a similar problem. Peter QTH was few miles for a AM 
station. The SPE amp is very sensitive, the signal from the AM station was 
strong enough to trip the amp. The solution was a 2 KW high pass filter to 
attenuate 30 db the signal from the AM station. Keep attenuation only as 
necessary to avoid the amp to trip and keep insertion loss very low.. You can 
use few  10W 10db  attenuator to figure out now much attenuation you need. If 
it is external signal coming in, you don’t need to transmit, the amp will trip 
just actuating the PTT.

73’s
JC
N4IS

Sent from Mail for Windows

From: WW3S
Sent: Friday, October 29, 2021 11:06 AM
To: FZ Bruce
Cc: topband@contesting.com
Subject: Re: Topband: amp tripping on 160

I have toroids on all the cables….and even started pulling cables out of the 
shack to see if it made a difference….im beginning to wonder if the amp has a 
fault….

Sent from my iPad


On Oct 29, 2021, at 10:57 AM, FZ Bruce  wrote:

It is likely RF traveling into the amp via multiple wires, cables. Recommend 
you put RFI cores on the coax between the radio and amp, and on the antenna 
coax near the amp.

( also possible getting on power supply connections)

73
Bruce-K1FZ

-

From: "WW3S"
To: "topband@contesting.com"
Cc:
Sent: Friday October 29 2021 10:44:39AM
Subject: Topband: amp tripping on 160

After two great nights of being able to receive, I am beyond frustrated,
as I cannot transmitsomething happened recently, and I cannot figure
it out... I suspect its RFI, but not sure why.as soon as I transmit
on my Inverted L, my SPE 1.3KFA amp trips, saying SWRT exceeds
limits.yet the SWR displayed is 1.46 to 1.new to me, but not
new to this season is my tower which holds my Inverted L.it was 50'
of Rohn 25, with a Hazer, its now a Alumnatower 48', with a
wonderpole...but.that setup did work, as I worked S9OK and
3DA0RU with itI added a second receiving loop in the front yard, so
thought that was it, but I took those cables out from the shack and
still have a problemyesterday morning, I found the short piece of
coax had a nick in it, from the mower I guess, so replaced it, and
shortened my L a bit to bring the SWR a bit further up the band.I
tested yesterday morning and it was great, low , mid and high power,
even 1300 watts of RTTY, no failure, I tried several times during the
day and all was great until darkness, and as soon as I keyed the amp,
failure.I pulled out what little I have left of my hair trying to
figure this out..the wonderpole is grounded and I "assume" the tower
is grounded thru that..should I separately ground the tower? Doing
so will complicate tilting it over, plus I only have copper grounding
attachments, I thought I read where I shouldn't use dissimilar
metals.but willing to try anything to get my 160 TX ability
back...thoughts?
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Searchable 

Re: Topband: Helium Ballon & SPE on 160m FT8

[Adrian]

Hi Luke, I have been working USA without issue, incl last night, However 
Europe was poor early this morning,


probably due to a slight breeze coming up. which brings the tethered 
balloon down substantially with a bad angle.


For operation analysis, I usually watch 
https://wind.willyweather.com.au/qld/darling-downs/laidley-heights.html


for wind conditions , which is useful, but like most weather forecasts, 
not always accurate, but a good guide.


This Sunday coming looks like a good time to setup again.


73


Adrian Fewster

On 25/3/21 8:57 am, List Mail wrote:


Hi Adrian,

Conditions to NA have been dreadful lately. They usually improve 
around the Equinox, but not so now.


Hopefully it will improve soon, to make your effort of the balloon 
antenna worthwhile.


GL DX, de Luke VK3HJ.

Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for 
Windows 10


*From: *Adrian <mailto:vk4...@gmail.com>
*Sent: *Thursday, 25 March 2021 2:58 AM
*To: *topband@contesting.com <mailto:topband@contesting.com>
*Subject: *Re: Topband: Helium Ballon & SPE on 160m FT8

Oops I see now K9FD is in Hawaii, Callsign tricked me.

So he was in the 'dark'.

Vk4tux

-Original Message-

From: Adrian [mailto:vk4...@gmail.com]

Sent: Thursday, 25 March 2021 1:54 AM

To: 'topband@contesting.com'

Subject: Helium Ballon & SPE on 160m FT8

Installed a new LDMOS in my SPE this week and have it on the Helium 
balloon up now ;


154730   0  0.1  974 ~  VK4TUX K9FD +07

Just worked above, must be daylight there now

Adrian Fewster

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Re: Topband: Helium Ballon & SPE on 160m FT8

[Adrian]

Oops I see now K9FD is in Hawaii, Callsign tricked me.
So he was in the 'dark'.

Vk4tux

-Original Message-
From: Adrian [mailto:vk4...@gmail.com] 
Sent: Thursday, 25 March 2021 1:54 AM
To: 'topband@contesting.com'
Subject: Helium Ballon & SPE on 160m FT8

Installed a new LDMOS in my SPE this week and have it on the Helium balloon up 
now ;

154730   0  0.1  974 ~  VK4TUX K9FD +07

Just worked above, must be daylight there now

Adrian Fewster



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Topband: Helium Ballon & SPE on 160m FT8

[Adrian]

Installed a new LDMOS in my SPE this week and have it on the Helium balloon up 
now ;

154730   0  0.1  974 ~  VK4TUX K9FD +07

Just worked above, must be daylight there now

Adrian Fewster



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Re: Topband: New Subject: 160M array feedline question

[Adrian]

Interesting page on the subject here ;

https://ham.stackexchange.com/questions/3675/what-is-the-effect-of-using-different-number-of-radials-with-ground-plane-antenn


On 23/3/21 1:55 pm, Guy Olinger K2AV wrote:
A counterpoise is what we do when the full size of a double-ended 
antenna, dipole, OCF, etc is too large for us to build, maintain, etc. 
Very simply, we want to jam the energy from the shield of our coax 
into the counterpoise, and the energy from the center conductor into 
the radiating element, the vertical, T, inverted L, etc, the aerial 
wire. Then we want to get all that energy back from the counterpoise, 
none lost if possible, at the phase reversal. Any you don't get back 
is mostly outright loss. With commercial high grade radials you can 
show that the effective series resistance of the counterpoise is 1/2, 
1/3 or sometimes even 1/10 of an ohm. That means that the aerial wire 
is radiating something like 50, 100 times the energy lost/radiated by 
the radials' connection to ground.


The two current destinations taken together MIMIC a circuit, because 
the current into the counterpoise is the same, but opposite polarity 
as the current into the radiating part of the antenna. If the currents 
are equal and opposite, it looks like a circuit, walks like a circuit, 
quacks like a circuit. You can model it with a fake circuit, and use 
Maxwell's equations for circuits to predict what is gonna happen. 
There is no magic circulation, just the ability to convince the coax 
it is hooked up to a circuit. With the massive parallelism of a 
commercial grade radial field, the radial's electrons are coupled into 
the ground as a reservoir, with the push back from extra or missing 
electrons that will return the current when the phase reverses. The 
more radials, the more even the radials, the longer the radials, the 
lower the power lost to current through resistive materials, lost to 
dielectric loss in dielectric materials, lost to resistance in the 
wire. Not perfect return, but a nice, high percentage return.


In free space, it is possible to construct a counterpoise that NEC4 
can accurately predict will radiate power to the far field at a rate 
30 dB below the RF current's energy. The essential loss is in the RF 
resistance of the wire. You are talking about a counterpoise that is 
98 or 99+ percent efficient in free space.


We are not interested in a counterpoise radiating, or invoking loss in 
the environment. Talking to the counterpoise, I'm telling it I'm 
giving it this pile of energy. A half cycle from now I want it all 
back. No skimming off the top. Maybe just a skoch.


A commercial quality radial field beneath a vertical is deliberately 
intended to be non-radiating. Looking at the current around the base 
of the vertical, the current to the east is exactly the opposite of 
the current to the west, as are to the north and south, as are all 
opposite radial pairs, therefore the fields generated are opposite, 
intended to be net zero in the far field. That's on purpose, pretty 
much true, and exactly what the engineers had in mind.


It is easy to show that there are unfortunate ham designs and 
implementations of the counterpoise/aerial concept where not even 10 
percent of the power is radiated skyward. That is the 160 meter two 
ton elephant in the room that gets ignored an awful lot of the time.


73, Guy K2AV


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Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: New Subject: 160M array feedline question

[Adrian]

Recycling signals at the feedpoint sounds more like a mismatch swr 
situation.


The ground radials form half of the antenna, and that radiation from 
ground, in phase with the vertical radiation determines the field 
strength and take off angle.


vk4tux


On 23/3/21 11:31 am, Charles Moizeau wrote:

I feel it more appropriate to say that the function of ground-mounted radials 
is to harvest the radiation from a vertical antenna that splashes on the ground 
and return it to the feed point for recycling.

72/73,

Charles, W2SH


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Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: On FT8 160m now using Helium Balloon antenna 40m high.

[Adrian]

Intend to do this again tonight here in VK4, as conditions look ok.

Please look out for me on 160m FT8, will be good to check sig reports.

I may look at FST4 also. 200w only. 1/4w vertical


73


Adrian Fewster


vk4tux

On 9/3/21 9:29 pm, Adrian wrote:

On FT8 160m now using Helium Balloon antenna,  40m high & 200w only (amp
getting repaired).

  


vk4tux

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Topband: On FT8 160m now using Helium Balloon antenna 40m high.

[Adrian]

On FT8 160m now using Helium Balloon antenna,  40m high & 200w only (amp
getting repaired).

 

vk4tux

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Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Testing FST4 on 160m

[Adrian]

Jim is economic on quoting callsigns, The VK4 is myself VK4TUX,

I have been testing FST4-300 will be back on FST4-60 tonight from ;


12:00 UTC till 15:00 UTC, which is 10:00pm to 1:00 am AEST here.

I work 1837.5 + 2K TX/RX mark


I will probably test FST4-300 after a FST4-60 session with N6SS, whom I 
see but cannot decode yet on 300, but I have worked on 60.



Thankyou

Adrian Fewster


vk4tux

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Re: Topband: My first VK on 160M!

[Adrian Van Der Byl]

Hi Mark
Glad you were able to work VK3IO and VK3HJ.
I pulled out of that opening in deference to others here due to spurious 
products on my transmission.
Best 73
Adrian VK2WF

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Mark K3MSB
Sent: Sunday, 1 April 2018 8:10 AM
To: topBand List
Subject: Topband: My first VK on 160M!

 Huge day for me this morning

After several years of trying, I worked my first VK on Top Band! Well, actually 
my first 2 Vks!!

Ron VK3IO had the honors at about 1045Z. Here's a recording of him CQing later 
at 1051Z, which is about 30 minutes before my local SR:

http://www.k3msb.com/dx/vk3io_1052z_31mar2018_160m.mp4

Shortly thereafter I worked Luke VK3HJ at 1101Z which is about 20 minutes 
before my local SR.

Over the past few years I've heard bits and pieces of VK signals, and copied 
Adrian VK2WFs complete call a few weeks ago. Those signals were only copyable 
on the NW RBOG antenna. This morning Ron copyable on both the NW RBOG as well 
as the INV-L.

My hands were shaking after those QSOs so I went upstairs and had a cup of
(non-decaff) coffee to “calm” down. My XYL Barbara and I then went out for 
breakfast, and I celebrated with a delicious country fried steak (smothered 
with gravy) and egg breakfast with more (non-decaff) coffee!!

What a morning here. country #131 for me on 160M and Zone #30 as well which 
is also my 30th zone on TB!

Thanks Luke and Ron!!

73 Mark K3MSB
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Re: Topband: Wednesday 160m DX Activity Night

[Adrian Van Der Byl]

Hi Steve

This evening (29 March) was much better, a number of RBN responses from AA4VV, 
VE7CC-7 and W4KKN.

It  opened up around 10:45z. Thanks for the QSOs with VE3MGY, N0FW and N7UA.

73

Adrian VK2WF

 

From: VK3HJ [mailto:vk3hj_l...@barefoothorse.com.au] 
Sent: Thursday, 29 March 2018 6:58 PM
To: vk2wf; topband@contesting.com
Subject: Re: Topband: Wednesday 160m DX Activity Night

 

Adrian,

 

You are about 600 km north of me. That is certainly a sufficient distance to 
make a difference. Steve VK7CW is about 550 km south of me.

 

I forgot to mention, Wednesday morning around 2030z I tried for Europe, and as 
per Wednesday evening, absolutely nothing in the log, nor any signals above the 
grass.

 

Let’s see if this evening is any good!

 

73,

 

Luke VK3HJ

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Re: Topband: Bottom End Beacons

[Adrian Fabry]

Yesterday evening they were S9 on my poor 6m high INV-L. The 1810-1820
interval is unusable here.

73 Ady YO2NAA

On Tue, Feb 20, 2018 at 11:09 PM, Jean-Paul Albert via Topband <
topband@contesting.com> wrote:

> Yes Mark , around 6 pm GMT time louder than the days before.
> Shorter propagation by the moment I suppose because no eastern station at
> the grey line today.
>
> 73´
> Jean Paul
>
>
> Envoyé de mon iPad
>
> > Le 20 févr. 2018 à 21:29, Mark van Wijk  a écrit :
> >
> > And just tonight they are loud again: https://www.flickr.com/photos/
> pa5mw/39676032834/in/dateposted/
> >
> > Signal level:  25dB above bandnoise
> >
> > RX antenna: 60mtr  BOG in a ditch QTF 30
> >
> >
> > 73
> > Mark, PA5MW
> >
> >
> >> On 2/20/2018 10:41 AM, Roger Kennedy wrote:
> >> Yes, upon searching, I came across Alan Cordwell's web pages that he
> wrote
> >> about the old Decca HiFix navigation beacons that used to be VERY strong
> >> here in Britain, but closed down during the 90s.
> >>
> >> I emailed him about these, as they sound very similar.
> >>
> >> He confirmed that they are a Russian system that works in much the same
> way,
> >> and have low power transmitter around the Baltic.
> >>
> >> As Mark posted, here's a link to Alan's webpage which shows you how they
> >> sound:
> >>
> >> http://alancordwell.co.uk/Legacy/radionavigation/russian/bras.html
> >>
> >> They are used by fishermen to pinpoint their position so they can locate
> >> fish stocks - that's why I referred to them as fishing beacons.
> >>
> >> I'm amazed some of you can hear them in the US, as they're rarely very
> >> strong here - typically between S2 and S9, but generally around S5.
> >>
> >> But the thing to remember is that there are about 15 of them spaced
> evenly
> >> between 1800 and 1820 kHz . . and they are quite wide.  So these will
> often
> >> block out weak DX signals here in Europe.  So worth avoiding that part
> of
> >> the band.
> >>
> >> Hopefully they will turn them off soon, and just use GPS !
> >>
> >> 73 Roger G3YRO
> >>
> >> _
> >> Topband Reflector Archives - http://www.contesting.com/_topband
> >
> > _
> > Topband Reflector Archives - http://www.contesting.com/_topband
>
> _
> Topband Reflector Archives - http://www.contesting.com/_topband
>



-- 
73 Ady
YO2NAA
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Re: Topband: Capacity Hat Wire Size

[Adrian Van Der Byl]

Sorry it seems the link I posted got broken.

https://www.facebook.com/photo.php?fbid=440029073004475=pcb.745473342286
826=3=1

73
Adrian 
VK2WF

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Adrian
Van Der Byl
Sent: Thursday, 4 January 2018 9:44 AM
To: 'Mike DeChristopher'; topband@contesting.com
Subject: Re: Topband: Capacity Hat Wire Size

I have to agree with Mike, physical strength is important.
I am on an exposed ridge where the winds are quite strong.
I use stainless steel wire rope as part of the top hat supported with 19mm
dia al tubing spokes.

https://www.facebook.com/photo.php?fbid=440029073004475=pcb.745473342286
826=3=1

Adrian
VK2WF


-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Mike
DeChristopher
Sent: Thursday, 4 January 2018 6:28 AM
To: topband@contesting.com
Subject: Re: Topband: Capacity Hat Wire Size

Bruce,

I used to resonate my tower on 80m with 22 ga wire in two directions.
Never a problem with power handling at 1.5kW; I probably would have used
bigger stuff if I had any in the garage at the time.

Like others here, I think the real issue is that these wires will become de
facto guy wires, and so physical strength becomes relevant.

73,
Mike N1TA


On Tue, Jan 2, 2018 at 10:31 AM, Bruce Osterberg <n9b...@gmail.com> wrote:
> Good Morning:\
>
> To improve my 160 vertical I want to change its configuration from an 
> inverted L to a Capacity Hat Vertical.  Vertical will be 57 Feet high 
> with Capacity Hat wires.  I am using an 18 Meter Spider pole.  I plan 
> on running
> 1.5 KW to it.  Looking at spider pole website it says 18 Gage wire for 
> the Vertical part and 26 Gage wire for the capacity Hat.  But it says 
> nothing about the power handling capacity of these wires, (both 
> vertical and horizontal).  I know the spider pole is a bit flimsy at 
> the 55 foot level so a smaller wire is needed but I am sure someone on 
> this reflector has the answers I need.
>
> Bruce N9BX 73
>
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Re: Topband: Capacity Hat Wire Size

[Adrian Van Der Byl]

I have to agree with Mike, physical strength is important.
I am on an exposed ridge where the winds are quite strong.
I use stainless steel wire rope as part of the top hat supported with 19mm
dia al tubing spokes.

https://www.facebook.com/photo.php?fbid=440029073004475=pcb.745473342286
826=3=1

Adrian 
VK2WF


-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Mike
DeChristopher
Sent: Thursday, 4 January 2018 6:28 AM
To: topband@contesting.com
Subject: Re: Topband: Capacity Hat Wire Size

Bruce,

I used to resonate my tower on 80m with 22 ga wire in two directions.
Never a problem with power handling at 1.5kW; I probably would have used
bigger stuff if I had any in the garage at the time.

Like others here, I think the real issue is that these wires will become de
facto guy wires, and so physical strength becomes relevant.

73,
Mike N1TA


On Tue, Jan 2, 2018 at 10:31 AM, Bruce Osterberg <n9b...@gmail.com> wrote:
> Good Morning:\
>
> To improve my 160 vertical I want to change its configuration from an 
> inverted L to a Capacity Hat Vertical.  Vertical will be 57 Feet high 
> with Capacity Hat wires.  I am using an 18 Meter Spider pole.  I plan 
> on running
> 1.5 KW to it.  Looking at spider pole website it says 18 Gage wire for 
> the Vertical part and 26 Gage wire for the capacity Hat.  But it says 
> nothing about the power handling capacity of these wires, (both 
> vertical and horizontal).  I know the spider pole is a bit flimsy at 
> the 55 foot level so a smaller wire is needed but I am sure someone on 
> this reflector has the answers I need.
>
> Bruce N9BX 73
>
> _
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Re: Topband: Inverted-L with coil on the top of the vertical section

[Adrian Fabry]

Hi James,

Thank you for the hint. I read the article, and I see t's a very good
solution. For the moment I can't install this elevated FCP.

I have to mention my soil is good, quite wet most of the winter.

73 Ady YO2NAA

-Original Message-
From: James Bennett [mailto:w6...@me.com] 
Sent: Wednesday, February 11, 2015 2:30 AM
To: Adrian Fabry
Cc: topband@contesting.com
Subject: Re: Topband: Inverted-L with coil on the top of the vertical
section

Ady - you might consider using a Folded CounterPoise, designed by K2AV, for
your radial system. I have one on each of my Inverted L antennas; 160  80
meters. They work quite well if you do not have the real estate for a lot of
radial wires. My 160 Inverted L only goes up 35-40 feet bit with the FCP it
performs very well. 




 On Feb 10, 2015, at 2:09 PM, Adrian Fabry yo2...@gmail.com wrote:
 
 Hello all,
 
 
 
 I'd like to build an Inverted-L antenna. Unfortunately the vertical
section
 will be only 8m (26 ft) high and the radial system not great (maybe 5 to
10
 wires laying on the ground)
 
 The simulation (with MMANA software) indicate 3.5 +j0 Ohm impedance. This
is
 very low so I think most of the power will be lost in the ground. 
 
 In order to raise the impedance, I would insert a coil (about 75 uH) on
the
 top of the vertical section and restore the resonance with 48.7 pF series
 capacitor on the feed point. 
 
 This will raise the impedance to 34 ohm. 
 
 
 
 Is this solution OK? Should I better place the coil at the feed point ?
 
 
 
 I know it would be much better to increase the height of the vertical
 section and to install more radials or a ground screen, but this is not
 possible for the moment, so I have to find the best compromise.
 
 
 
 
 
 Thanks for reading.
 
 
 
 73 Ady YO2NAA
 
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Topband: Inverted-L with coil on the top of the vertical section

[Adrian Fabry]

Hello all,

 

I'd like to build an Inverted-L antenna. Unfortunately the vertical section
will be only 8m (26 ft) high and the radial system not great (maybe 5 to 10
wires laying on the ground)

The simulation (with MMANA software) indicate 3.5 +j0 Ohm impedance. This is
very low so I think most of the power will be lost in the ground. 

In order to raise the impedance, I would insert a coil (about 75 uH) on the
top of the vertical section and restore the resonance with 48.7 pF series
capacitor on the feed point. 

This will raise the impedance to 34 ohm. 

 

Is this solution OK? Should I better place the coil at the feed point ?

 

I know it would be much better to increase the height of the vertical
section and to install more radials or a ground screen, but this is not
possible for the moment, so I have to find the best compromise.

 

 

Thanks for reading.

 

73 Ady YO2NAA

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