The 160m Band Utilization Chart has been updated. It now shows the JT9
dial frequency at 1.8395 MHz. The chart is at:
http://homepage.ntlworld.com/wadei/160m_band_utilization.htm
The chart is still sparse on detail, so if you have anything to add to
it, please let me know: mailto:
CU on the 525 foot band, Carl? Seriously, I suspect that the reason why
many of us work in meters when modeling is simply that some of the most
useful software products default to that.
73, Pete N4ZR
Check out the Reverse Beacon Network at
http://reversebeacon.net,
blog at
The Alpha 77-SX is a great amplifier with plenty of reserve. The plate
voltage runs just under 4KV on the Hi-Power position. If you go to the
larger transformers you are asking for trouble. The filter capacitor has
to be changed to one with a 5 KV rating. When you do this you will push
circuit
GM Pete et al:
That metric stuff is widely used around the globe.
Cu on 459 ft.
73
Len SM7BIC
On 11/14/2012 3:48 PM, ZR wrote:
I cant find the button to convert that metric stuff to good old USA
measurements when posted from this country(-:
___
PoĊĦiljalac: Lennart M lennart.michaels...@telia.com
That metric stuff is widely used around the globe.
It's fun to learn that Dr. Maxwell, the inventor of electromagnetic waves,
had used metric units exclusively 200 years ago.
So, why we cannot do the same today?
73,
Sinisa YT1NT, VE3EA
If something goes wrong in the RX antenna switch, you don't have to
worry about the rig transmitting into its own receiver. That can't
happen. The only thing that can happen is that you could damage the
antenna or its preamp. The reed relay is just like the one in your
radio, so it shouldn't
Dry blowing snow or high wind can cause quite some voltage build up on a
antenna, especially a long one. It is possible to draw quite an arc to ground.
There have been reports of high voltage electrocutions from antenna static
build up in Short Wave Broadcast stations. A short stick was
Why not prevent the static buildup in the first place? I use 33K resistors
from each wire to ground. Schematic is at
http://www.w0btu.com/Beverage_antennas.html .
The components in parallel with the 33K resistors are 90 volt gas discharge
tubes, and the resistors are to prolong the life of those
Hello all, looks like V84SMD is not very active on 160 ! Do we know why ?
thank you
Jacques F6BKI
___
Topband reflector - topband@contesting.com
On 2012-11-15, at 3:42 PM, Bruce wrote:
Dry blowing snow or high wind can cause quite some voltage build up on a
antenna, especially a long one. It is possible to draw quite an arc to
ground.
There have been reports of high voltage electrocutions from antenna static
build up in Short
Good point Mike, but I am hoping someone has done definitive testing
between
insulated and un-insulated wire concerning voltage build up. If the
voltage
is lower with insulated wire there is less to bleed off, and possibly lower
noise activity.
http://www.qsl.net/k1fz/beveragenotes.html
Many tnx to all who replied offline with advice and help.
I am on the right track and hope to complete the project today.
73 Frank VO1HP
---
I am in the process of building a pennant.
I'm stuck on the
On 2012-11-15, at 4:35 PM, Bruce wrote:
Good point Mike, but I am hoping someone has done definitive testing between
insulated and un-insulated wire concerning voltage build up. If the voltage
is lower with insulated wire there is less to bleed off, and possibly lower
noise activity.
Hi Eddy,
Yes, above some voltage all insulators let high voltage through. Most common
wire insulation is only good for about 600 volts. Take care not to become a
bleeder resistor. Your idea of the RF choke is better than resistors to ground
as there should be lower signal loss.
GUD DX OM.
See
Hi Bruce,
Sure, and I'd be interested in knowing that, too. :-)
I should add that the GDTs were added after a lighting hit in the vicinity
caused windings to open up on the transformers. The GDTs were to prevent
that, and the resistors were to minimize the number of times that the GDTs
conducted
Out of curiosity, has anyone ever really done testing of voltage buildup
on a insulated antenna wire, VS a non-insulated wire ?
Indoor antennas VS outdoor antennas of equal size?
I tested this extensively years ago, and there was no difference at all
except if the insulation was in an area
I'm more interested in the 'limiters' aspect of the other thread. Back-to-back
diodes == bad, but am looking for something to better tame RF coming in on my
beverages, or whatever leaks by the bandpass filters on the 'other' station
antenna in a multi-multi.
Some sort of saturable transformer
Hi Tom,
Thank you for the information, It sounds very convincing.
As you have said it is difficult to get a A-B test unless instant switching
or direct observation is available.
I was hoping for a test something like, side by side identical wires, one
insulated, and one un-insulated with
Brian Moran wrote:
Some sort of saturable transformer design, like
http://www.arraysolutions.com/Products/as_rxfep.htm ?
What is interesting about this is that it uses T1-6 transformers,
which I have been using and recommending for years for RX antenna
use. I have repeatedly been told that
As you have said it is difficult to get a A-B test unless instant
switching or direct observation is available.
The purpose of my test was to see if p-static was caused by individual
charged particles as they hit the wire, or some other mechanism like corona
discharge into the charged air or
Tom,
Thank you for your research and information. You have me convinced
My much lower BOG Beverage has a better signal to noise than my taller
Beverages in storm events. This aligns to your research.
73
Bruce-K1FZ
- Original Message -
From: Tom W8JI w...@w8ji.com
To: Bruce
I used to have an ICE model 303 lightning protector which I believe
was a gas discharge tube with a toroidal choke in parallel to ground.
I recall the toroidal choke was to continually bleed the electrons
from the antenna so there would not be a buildup sufficient to cause
damage and to not
Not that Ive noticed.
I suspect most Americans are more comfortable with our own measuring system
plus our ham bands where antenna formulas are still published in feet and
inches.
Carl
KM1H
- Original Message -
From: Pete Smith N4ZR n...@contesting.com
To: topband@contesting.com
I did a search for K2UO here and didn't see anything recent, so I thought I
would post the article again for those with Low Dipoles or tight spaces.
Mentioned in ON4UN's book.
http://vss.pl/lf/14.pdf
K2UO was #61 for North America (2009) with an antenna that is 12-30ft high on
flat land was
Ive made several contacts up to about 2500 miles (West from NH) running 100W
into a single 750' #12 copperweld Beverage up about 8' using a FT114-43
autotransformer back in the 80's at a prior home. These were mostly on CW
during contests; the terminator was a 600 Ohm 100W NI resistor and the
I suspect most Americans are more comfortable with our own measuring system
plus our ham bands where antenna formulas are still published in feet and
inches.
I suspect most (or at least many) Americans are resistant to change
and unwilling to give anything different than what they are used to
Gosh, Paul.why don't you simply keep measuring in our system and avoid the
obvious mental wedgie you keep forming PLUS you won't be so weary?!?!?!
72, Jim Rodenkirch K9JWV
Date: Thu, 15 Nov 2012 18:58:48 -0500
From: p...@n1bug.com
To: z...@jeremy.mv.com
CC: topband@contesting.com
All,
This argument has been going on ever since I got out of Engineering school,
and frankly, it's not going to stop until my generation is gone. I'm an
EE and I work in my own machine shop in my (new) retirement. I work in
Imperial units because I THINK in Imperial units - it's what I learned as
Subject: Re: Topband: Covered /bare antennn wire
As you have said it is difficult to get a A-B test unless instant
switching or direct observation is available.
The purpose of my test was to see if p-static was caused by individual
charged particles as they hit the wire, or some other
Subject: Re: Topband: Covered /bare antennn wire
Tom,
Thank you for your research and information. You have me convinced
My much lower BOG Beverage has a better signal to noise than my taller
Beverages in storm events. This aligns to your research.
73
Bruce-K1FZ
That has nothing to do
Since I started this thread, hopefully this will end it. I was talking about a
difference on the order of 6' - 9', which I think was understood. But there
are always those few that like to stir the pot, no matter how petty. Thanks to
those who provided useful feedback. I'll follow up
-- Forwarded message --
From: Herb Schoenbohm he...@vitelcom.net
Date: Thu, Nov 15, 2012 at 5:22 PM
I used to use at first the MFJ-1026 Noise Canceller/Phaser box in a
reverse configuration to bring the RX only antennas in from the Beverage
bank. With the RF sense switch there
Here in South Africa we always had the imperial system till somewhere in the
middle sixties and before that we changed from pounds to decimal Rand and
cents.
It was met with some resistance but soon everybody got used to it.
As I have a British lathe and milling machine in my garage /workshop,
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