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Locked Quick and easy AM broadcast antenna

 

THE STORY:
I bought a new Sharp compact stereo and the AM reception is worse than horrible with the supplied 8-loops-of-wire-on-a-plastic-form "AM antenna." My 20 year old Aiwa that I replaced had the same exact plastic antenna but with 6 loops of wire.

I went to Goodwill and bought a $3.99 clock radio thinking I'd take the ferrite rod antenna out, wrap some wire around it, and voila, plug it in as an external antenna. While looking closely inside, I see that the ferrite rod is actually connected to the tuning capacitor and is part of a resonate circuit so I put the the radio back together, checked it for working again, and I'll use the in-store credit to buy a shirt.

GETTING CLOSE TO THE QUESTION:
Last night I got on Ebay and found 200' of 10/46 Litz wire for $7 and ordered it.? This hair-brained idea is to wind the small Litz wire on the stock wire - loop form and get better reception (more turns is better, right?)

THE QUESTION:
Can I use 200' of small Litz wire, when it arrives, in place of the supplied antenna of the short 8 wire loop and get better AM reception? I really don't want to have an antenna that I have to tune with an external capacitor.? Of course I'm OK with spinning it around to adjust for maximum signal.

Thanks in advance.


Locked Re: Modeling inductively loaded loop (was Re: Re:)

 

Let's cut to the chase, per the author:

?The helical loop (#3) is the least efficient, also as expected due to the extra length copper conductor, increased skin effect ?and current crowding losses.


BTW, that was 12.5 mil copper tape he used, and not all quote "copper" unquote alloys posses the same conductivity.

Overall, I'm surprised the correlation was within 1.5 dB given differences; I would have used 1) a larger diameter form and 2) greater spacing between turns and 3) constructed a reference loop using the same copper tape.?

BTW, if you start letting W8JI write your physics handbooks you will set 'science' back about 100 years ... he's right when it comes to bread and butter mainstream 'hammy' issues but runs out gas on the fringes (IOW he is not a physicist.)

Jim
??


Locked Re: Modeling inductively loaded loop (was Re: Re:)

 

Folklore dies hard.

At a recent ham convention some clown brought his
helically loaded loop and put it on display. He
proudly held court and explained to anyone
who would listen about how great it was. I
bet my 4 inch Hi-Q screwdriver with CB whip
on top could beat that loop in a shoot out.

Rick N6RK

On 12/6/2014 1:48 AM, qrp.gaijin@... [loopantennas] wrote:
In loopantennas@..., <richard@...> wrote :


> It has been experimentally verified countless times that helically
> loaded verticals have no special properties compared to conventional
loading coils. Why should it be different with loops?
The detrimental effect on efficiency of helical winding of a small loop
has finally been verified in practice by K4HKX with experimental data
measured using the Reverse Beacon Network and carefully controlling for
environmental parameters. The result: helical winding introduces loss,
about 1-2 dB with K4HKX's loop, compared to a non-helically-wound loop
of equivalent enclosed area. W8JI already pointed this out more than
thre! e years ago when the helically-wound loop was first proposed.
Quote by W8JI: "Regretfully, all helcially winding the small loop does
is increase inductance and loss resistance. It is of no benefit at all
for radiation." (Reference: )

The measured objective data showing this conclusion can be seen here:
(see "Section 3: Magloop Comparisons vs My
Reference 40M Dipole:" and "Section 9: Helically Wound Magloop".

Simply winding the strap non-helically around the support frame would
improve efficiency (see for example K4HKX's aluminum strap loop) by
reducing the current path length and the loss resistance.

!
Best regards,
qrp.gaijin@...


---In loopantennas@..., <richard@...> wrote :

On 8/30/2014 6:12 AM, jwin95@... <mailto:jwin95@...> [loopantennas] wrote:

> Rick, since I have seen differences between 'real life' and what
NEC-2
> based MOM modelers yield regarding loop antennas, I don't have quite the
> 'faith' you do in their infallibility. Were it not for the fact that a
> helical loop is not a simple planar (2-space) structure but occupies a
> non-trivial amount of volume in 3-space I would still like to see a
> basis-in-physics explanation outside of the reliance of the usual
> modeling programs.

It would be very easy to build a loop and put in lumped element
inductors to experimentally verify that magic happens or doesn't happen.
But consider this thought experiment. If the loop radiation
resistance is only 0.013 ohms, any coils you insert with more than a few
dozen ohms of reactance add significant losses relative to 0.013 ohms.
But a few dozen ohms of reactance has negligible effect on anything. A
helically wound strap is not a free lunch. The total conductor path is
longer and narrower, hence increasing losses.

It has been experimentally verified countless times that helically
loaded verticals have no special properties compared to conventional
loading coils. Why should it be different with loops?

>
> Yet to be explained as well is the phenom where Ae > physical size as it
> may apply to loops.

What is it that hasn't been explained? Lots of antennas have
Ae > physical size. That doesn't mean that helically wound loops
have additional Ae. Where physical size comes into play is that
you cannot simultaneously have small physical size and high efficiency
without extremely narrow bandwidth and limited power handling due to
the necessarily high loaded Q. The proof of this is independent of how
the antenna is constructed. The article originally cited makes no
mention of bandwidth.

Rick N6RK


Locked Vacuum Variable Cap Capacitor Wanted

 

Hi all,
I am wanting to modify my AMA4 80/160m loop to have a vacuum cap
Would like it to be around 20pf to 600pf 15KV

Paul G0HWC


?





Locked Re: Modeling inductively loaded loop (was Re: Re:)

 

In loopantennas@..., <richard@...> wrote :

> It has been experimentally verified countless times that helically
>?loaded verticals have no special properties compared to conventional
> loading coils. Why should it be different with loops?

The detrimental effect on efficiency of helical winding of a small loop has finally been verified in practice by K4HKX with experimental data measured using the Reverse Beacon Network and carefully controlling for environmental parameters. The result: helical winding introduces loss, about 1-2 dB with K4HKX's loop, compared to a non-helically-wound loop of equivalent enclosed area. W8JI already pointed this out more than three years ago when the helically-wound loop was first proposed. Quote by W8JI: "Regretfully, all helcially winding the small loop does is increase inductance and loss resistance. It is of no benefit at all for radiation." (Reference:??)

The measured objective data showing this conclusion can be seen here:??(see "Section 3: ?Magloop Comparisons vs My Reference 40M Dipole:" and "Section 9: ?Helically Wound Magloop".

Simply winding the strap non-helically around the support frame would improve efficiency (see for example K4HKX's aluminum strap loop) by reducing the current path length and the loss resistance.

Best regards,
qrp.gaijin@...

---In loopantennas@..., <richard@...> wrote :

On 8/30/2014 6:12 AM, jwin95@... [loopantennas] wrote:
> Rick, since I have seen differences between 'real life' and what NEC-2
> based MOM modelers yield regarding loop antennas, I don't have quite the
> 'faith' you do in their infallibility. Were it not for the fact that a
> helical loop is not a simple planar (2-space) structure but occupies a
> non-trivial amount of volume in 3-space I would still like to see a
> basis-in-physics explanation outside of the reliance of the usual
> modeling programs.

It would be very easy to build a loop and put in lumped element
inductors to experimentally verify that magic happens or doesn't happen.
But consider this thought experiment. If the loop radiation
resistance is only 0.013 ohms, any coils you insert with more than a few
dozen ohms of reactance add significant losses relative to 0.013 ohms.
But a few dozen ohms of reactance has negligible effect on anything. A
helically wound strap is not a free lunch. The total conductor path is
longer and narrower, hence increasing losses.

It has been experimentally verified countless times that helically
loaded verticals have no special properties compared to conventional
loading coils. Why should it be different with loops?

>
> Yet to be explained as well is the phenom where Ae > physical size as it
> may apply to loops.

What is it that hasn't been explained? Lots of antennas have
Ae > physical size. That doesn't mean that helically wound loops
have additional Ae. Where physical size comes into play is that
you cannot simultaneously have small physical size and high efficiency
without extremely narrow bandwidth and limited power handling due to
the necessarily high loaded Q. The proof of this is independent of how
the antenna is constructed. The article originally cited makes no
mention of bandwidth.

Rick N6RK
?


Locked Re: Pixel Pro-1a rotator suggestions?

 

Hi John;

I am using an AR-303 rotator with a small resonant loop, and have had this mounted outdoors for about 3 years now.? This appears to be identical to the RS unit.? I have had no problems with the rotator head itself, and it has worked without problems here in Chicago in temps down to -20F.? I do not use it for DFing or signal nulling, but tweak it occasionally to depress local noise as heard on the loop.

The control itself has its issues, and I have had to open it a couple of times to find and remove pieces of broken plastic which jammed it up.? This appears to be a common problem, but none of the problems I have had have been game enders.

For $50 this is a good deal and should work fine, especially for an indoor siting.

joe


Locked Pixel Pro-1a rotator suggestions?

 

I mounted my previously outdoor mounted Pro-1a and it's 5 ft mast into a CM tripod base and sat it in the floored walkup attic of the garden home I moved to 7/13. It's a bit of a trip to go for the trek to the other end of the hose, thru a door, upstairs, thru another door, and back to roughly over the office where I have my 'shack' - then turn the antenna - and return. I couldn't tell which direction the null is now, either! I need a rotator! I am considering the RS 15-1245 rotator ($60 less $10 'coupon'...), as it looks to have a rotation 'indicator' of some sort. I imagine it's not inherently synchronized - but should last as the temperature extremes of my attic are all it will have to contend with... hopefully! Suggestions/opinins/use-reports would certainly be appreciated! Thank you.


John


Locked File - Links.txt

 

Active AM Antenna With Twin Coil Ferrite by C. Crane Co.


JLKolb?s antenna links including the KRS AA-1 Active Antenna schematic, antenna preamplfiers, center-tapped loops, and a dual gate FET preselector.


Directional Terminated MW/LW Loop by WellBroook (UK)
K9AY is the Remote Controlled Variable Termination; Provides a Cardioid Reception Pattern with up to 30dB Gain Front-to-Back; Uses Two Delta Loops.


Kiwa - High Performance MW Air-Core Loop Antenna
High Performance MW Air-Core Loop Antenna by KIWA


Palomar Engineers Loop Antennas LW-MW-SW2
Palomar's Loop Antenna gives superb performance on the AM medium-wave broadcast band. The loop rotates and tilts to give deep nulls so you can eliminate local interference. It also allows you to null out a station and listen to another one on the same frequency.


The Quantum loop antennas, now V2.0


Terk AM loop at Amazon.com
Here is a place you can buy yourself a TERK AM loop antenna, even some other stuff that is kind of off topic to talk about. 73


WL1030 by the late Maartenhagg. Plans placed on this website by his friends in his honor.


C Crane Company
They sell the Justice AM Loop Antenna, Select A Tenna, Terk AM 1000


Kiwa Electronics
Kwia makes the best products for you and your radio equipment, and also improves things that needed improvement a long time ago.


Stormwise Ferrite Rods
Get some huge ferrite rods and a converter to go along with its, heck it even comes with project book.


Universal Radio Company
They sell all sorts of loops big and small for LW/MW/SW and VLF also 10 kHz to 15 MHz



ALA-1530
Find the best UK LF/MF antenna here.


AOR
This is the site that sells the AOR loop


Kiwa Electronics
The maker of the air core loop antenna and other useful items that you may want on your wish list.


LF Engineering Company
A group of engineers, who make products for VLF/LF listening even ELF loops!


Select A Tenna by Intensitronics Corp
The maker of the select A tenna, a great AM loop antenna that is a little bigger than the terk
discontinued

Terk Technolegies
The maker of the best sold AM and I use also called the AM-1000 AM loop antenna, there is also technical information on how it works.


Torus Tuner Loop Company
A very specially made loop that is almost as big as a hula hoop
discontinued


GRAHN (Germany) Specialized Loop Antennas for MW and SW Reception Contributed by radiohighfreq
Grahn offers both Ferrite Rod Antennas and Shielded Loop Antennas. Translated from the Gremany Language Webpages here is the "Grahn Specialized Loop Antennas for MW and SW Reception" ULR Address:
Use the Google Translate a web Page Tool to convert these webpages to English.



When considering AM Loop Antennas . . .
- - - It all comes down to Time? & Money?

How much Time? Are you going to be 'using' the Loop Antenna for
DXing or simply for "Better" AM Radio Reception (Sports/Talk Radio
Loop).

How Much Money? Are you willing to spend for a Loop Antenna to get
the kind of better reception you want.

TBL: Time and Money translates to the AM Loop Antenna's Value to You.


The average radio listener (97%), who wants better AM Radio
Reception, can spend $100 or less and get an AM Loop Antenna that
meets their needs.

Here is a brief list of the more common AM Loop Antennas for $100 or
less.

* Twin Coil Ferrite AM Loop Antenna (Active)
- - -

* Torus Tuner 27" Loop Antenna (Passive)
- - - discontinued

* Select-A-Tenna Model #541M (Passive)
- - - discontinued

* Terk AM Advantage Loop Antenna (Passive)
- - -

* RadioShack AM Loop Antanna # 15-1853 (Passive)
- - - Discontinued (Find 'used' on eBay)

* MTM Scientific AM Radio Loop Antenna (Passive)
*
- - - Starter Kit, Deluxe Kit or Finished Antenna!

* * * Home made 'Box' AM Loop Antennas
- Usually 20" to 24" in size
- - Generally a simple Passive antenna
- - - Can be made Active with an add-on amplifier


#1. * Justice AM Loop Antenna (Active)
- - - discontinued
#2. * Torus Tuner 27" Loop Antenna (Passive)
- - - website gone
#3. * Select-A-Tenna Model #541M (Passive)
- - - website gone
#4. * Terk AM Advantage Loop Antenna (Passive)
- - -
#5. * RadioShack AM Loop Antanna # 15-1853 (Passive)
- - - Discontinued (Find 'used' on eBay)


* MTM Scientific AM Radio Loop Antenna (Passive)
*
- - - Starter Kit, Deluxe Kit or Finished Antenna!

* * * Home made 'Box' AM Loop Antennas
- Usually 20" to 24" in size
- - Generally a simple Passive antenna
- - - Can be made Active with an add-on amplifier


NOTE: Beyond $100 in the $200 to $400 range are the
#1.a. Kiwa MW Air Loop Antenna

#1.b. Quantum Loop Antennas

. . . #3. Palomar Loop Antenna


Basic Wire Back Yard Loop Antennas
Full-wave loops are very popular antennas. They are especially useful on 80 and 40 meters where they perform well at modest heights. These are closed loops that are one full wavelength long. Horizontal loops may be fed at any convenient spot. For best performance, make your horizontal loop into a square, especially if it is to be used on several bands.


K9AY: How to Build the K9AY Loop Receiving Antenna
AY Technologies Antennas by K9AY. Excellent Antenna for Medium Wave Frequency DXing.


Six Foot Square by Six Turn Loop Antenna
New Mid-Size Loop Antenna by Graham Maynard with Matching Balanced Amplifier: Frequency Range 50KHz - 5000KHz.


Ten Foot Receiveing Loop for Low-Frequency DXing
A Page out of VE7SL's Note Book. This 10 Ft. Air-Core Receiving Loop was originally designed and constructed for NDB DXing and now is used for LOWFER DX work.



Dave's HomeMade Loop Antennas
This is the loop antenna my dad built in 1958. Although I was only 8 years old at the time, I knew what this was for and how it worked. WebSite/Pages produced by Dave Schmarder Page Contributed by radiohighfreq


4 Foot Box loop antenna
Heres a 4 foot loop project by Bruce


ATL-3 Loop Antenna by Graham Maynard (UK)
Loop & Amp Project: ATL-3 Loop Windings are in the Shape of a Five 26" Sided Spiral


Alt-Azimuth Wooden "HOOP LOOP" Antenna by Linus
The Great Pumpkin" Speaks on "How To Make" a Loop Antenna from a Wooden Embroidery Hoop. Read the Exciting Saga of his journey in to the Kingdom of Hooppy-Looppy-Dom presented by RadioIntel.Com.


DXers Tool Box - DIY - Tuned Loop Antenna
The DXers Tool Box "How To Build" a Tuned Loop Antenna = How can you vastly improve your Medium Wave reception? The antenna consists of an LC (tuning) circuit formed by the air-core loop and a tuning capacitor.


Embrodary Loops
While these loop are for crafts, they can be a craft of art for improved AM radio reception!


Hard Core DXing
Here's what nordic dx has to offer in their discription of loops in this website


K5DKZ - Three Foot Box Loop Antenna Kit
Complete Parts and Plans for a 3 Ft Box Loop Antenna "Kit" ~$85+SH


KIT -by- MTM Scientific, Inc. -for- AM Radio DX Loop Antenna
KIT =//= Designed to Build an AM/MW Radio DX Loop Antenna =//= Offered by MTM Scientific =//= Deluxe Loop Antenna Kit: Includes ALL the Hardware for Building this AM/MW Radio DX Loop Antenna.


Long LoopStick Antenna for MW DXing
Wound on a Three (3) Foot Length of PVC pipe, the "Long LoopStick Antenna" was an experiment to try to improve AM radio reception without using a long wire or ground.


TL Loop Receiving Antenna 10 KHz - 30 MHz
The principle of operation is that an rf voltage appears across the terminals of a loop when it is placed in an electromagnetic field. The voltage is proportional to frequency for a given field strength and so at Very Low Frequencies the voltage is very small and requires greater amplification but it is not quite as simple as that. The new TL Loop uses a unique feedback system to optimise the amplification/noise factor over a much wider range than has been possible hitherto.



W2BRI Xmit Loops Contributed by n3hkn
Ham Radio xmitting loops. Detailed plans and reports from Hams experiences. Typical cost is $50 for pipe, capacitor, motor.


"AM Loop Antenna Calculator" - by Bruce Carter
Here is a Great Tool for those Loop Antenna => "What Ifs...."


"Loop Antennas 101" Read This First
Minnesota DX Club's Loop Antenna's web page that is a 'Must Read' =Says It All= A Starting Point Class 101- - - TOPICS: Principles of the Loop Antenna - What is a Loop and Why Use It - Construction Principles - What Can I Use a Loop For - Loops Another Look - Pictures of Home Built PVC loops - Loop Links


* NEW => 2002 AM Loop Antenna Construction "Tips" by Bruce Carter
Introduction / Why Another Loop Antenna Page? / Mathematics of Rectangular Loop Antennas / Construction Articles / Loop Antenna (and Related) Links


Loop Antennas at Hard Core DX
TABLE: Number of Turns -v- Size of Loop in the Middle of this webpage.


Loops and Rods =&= The Ferrite Rod Antenna
Theory / Formulas / Drawings = The use of a small Magnetic Loop as an antenna. The ferrite has the effect of intensifying the magnetic field inside the loop.


Modify the common AM Radio Loop Antenna
Hard-Core DX & Nordic DX = Topics: Install Larger Ferrite Rod - Fix External Antenna -Add a Long Wire - Or a Loop - Construct it - Connect it - Add an Amplifier. Presented by Bruce Carter


Sensitivity of Multi Turn Receiving Loops
LWCA - Multi turn wire loops are often used as low frequency receiving antennas. Basic electromagnetic theory is developed here as it relates to electrically small multi-turn loops at low frequencies. - Presented by William E. Payne, N4YWK


Using the Small Loop Antenna by Joe Carr
DXing.Com presents Joe Carr's Radio Tech Notes: Eight Page PDF Document provided by Universal-Radio.Com



How to Get Better AM Radio Reception
Features Loop Antennas and much more. The Antenna is 90% of Your Radio. Still Need More Signal? Try a Better Antenna.


Introduction to Broadcast Band AM/BCB/MW DXing
The International Radio Club of America (IRCA) WebPages



** Radio-Antenna-PRO ** H.Hertz-Forum
Remember you may need some Russian Text software for this groupThe international forum for radioengineers, scientists and hams. All about radioelectronics, radiocommunications, radiophysics, electrodynamics. About 250 members from 20 countries. In Russian language. Very active. Lot of interesting researches and discussions.



Radio DXing with The Interference Problem
This is great for that annoying problem you have with your loop antenna, and you may think its the loop, think again it could be that messed up street light, next doors dimmer switch, and other something else you can't probably solve with just a loop antenna.



"3805er" 80-Meter balanced coax loop
Small shielded rx only loop for 80 meters


Magnetic Loop Antennas Receiving - by W8JI
This WebPage's Topic Are: - Small Receiving Loops - Loop Antenna Fields - Dipole Antenna Fields - Radiation - Loop Shielding and Balance - by W8JI


Radiation and Fields (Magnetic Loop Antennas) - by W8JI
This WebPage's Topic Are: - Electric Field - Magnetic Field - ElectroMagnetic Field - Near the Antenna - Losses - Near Field - Fresnel Zone - Farfield - Summary - by W8JI


Shielded-Loop Receiving Antenna by N5FC
Shielded-Loop antennas have some nice properties that make them desirable as portable receiving antennas.


Antique Electronic Supply
A sorts of older variable tuning capacitors for your loop antenna that needs one bad.


Fair Radio Sales
A wide variety of electronic components, radios, and variable capacitors for your loop antenna


Ocean State Electronics
Rhode Island's best selection for a wide variety of the best tuning capacitors for reasonable price, tell them that electronicdx (Adam Ebel) sent you.


The Crystal Set Society
Here are some capacitor available from a club that devotes to Crystal Set Radio


The Surplus Sales of Nebraska
This surplus store based in the state of Nebraska, has the one you might need, but they have minumim order policy



Dan Small Parts and Kits
Dan's wide selection from Canada.



American Science and Surplus
A big spool of wire here just about for AM


DigiKey.com
For ribbon cable and other sorts of wire.


Femco Magnet Wire
Femco Magnet Wire is a joint venture company that has been supplying round insulated copper magnet (winding) wire to the transplant market since 1988.


Litz-Wire,com
Welcome to Litz-Wire.com!


MCM electronics
They do sell wire and magnet wire here


MWS Industries
A place for all sorts of wire for business and industry


Magnet Wire from Radio Shack
This is what I use often


Mouser Electronics
Mouser has the biggest spools here for a great price, that makes sense


Ocean State Electronics
magnet wire at a good price


WIRE "Flex-Weave" Antenna Wire
"Flex-Weave" is a hybrid aerial wire that consists of 168 strands of woven #36 solid copper wires that provide high strength and extreme flexibility. The most popular version of "Flex-Weave" is the 'equivalent' of #14 AWG wire size. It can be 'used' for unsupported spans up to 200 ft (100-150 ft in areas with high ice and wind loading).


WIRE "QuietFlex" Antenna Wire by Antennas & More: Insulated, Strong, Flexible and Durable
"QuietFlex" Antenna Wire by Antennas & More: "QuietFlex" #14 AWG Wire has more than 41 Strands tightly twisted together under its Flexible Insulation making it both Strong, Flexible and Durable.


Scanning, Ham Radio and Public Safety Resources
- Links to the various webpages with resources for the Ham Radio Operator and Scanning Enthusiast. Resources such as; Monitoring Police and Fire Communications, What Antennas to use, Secret Scanner Frequencies, Radio Programming Software, Radio Mods and Operating Tips, Professional resources for Public Safety Management, Guidance and Self-Help.


Amidon Ferrite rods, bars, plates, and tubes.


Bytemark Ferrite rods, bars, plates, and tubes.


Locked File - UploadingFilesLinksPhotos.txt

 

If you have a link relevant to the group, please post it in the Links section. If you just put it in a message, it will get lost in the shuffle after a few days. The coverage of the list is pretty broad.

All members can upload Links, Files, and Photos.

A few guidelines:

Try to place them in the proper folder, if it exists. If not, you can either just put it in the root folder and eventually I'll move it into the proper place, or create a folder.

When creating a folder or uploading a file or photo, please don't use spaces or punctuation. You can either use caps for the first letter of each word, or use underscore as a space.

Like this: "4x8Loop" or "4x8_loop" or "Steves_4x8_Loop"

Not like this: "Steve's 4 x 8 Loop." That goes for Folder names and File names.

A special note about the Photos section: Please crop in to the important parts. For photos, JPG saves smaller and looks better, for line drawings GIF is smaller and looks better. Please do not use TIFF/TIF or BMP files, the file size is way too big and I may delete without notice.

Feel free to ask if you need help figuring out how to crop and resample. Irfanview is a fairly easy to use program that loads just about any file, you can crop and resample from there:

Or for more complex stuff, another free program is GIMP:

Attachments are now allowed, but please use judiciously. Rather than going out with the messages, they will be stored on the list but you'll get a link with the message.

A last note: if you see something in any folder or in the messages that looks like spam or simply inappropriate, don't post on the list- email me directly and tell me about it and I'll take care of it with a minimum of fuss.
loopantennas-owner@...

Thanks,
Steve Greenfield


Locked Maybe interessting for your link list

 

Hello dear OM,


there is a new online community for ham radio operators with many features available.
The website URL is www.socialhams.net, please have a look and maybe your are
interessted in adding the link to your directory. We would be glad to see you joining the
community too.


Thanks in advance!


vy 73 de Andreas
OE8APR



Locked Re: Active loop antenna

 

I need schematic for wl 500 to. Thanks Railroad


Locked Re: AOR LA800

 

¿ªÔÆÌåÓý

Thanks Stephen,
?
I would expect that a tuned loop would provide at least a 10dB improvement in s/n compared to any Broadband loop; assuming? that both antennas are used in quiet RF environment.
If you suspect the AOR is bad; is it possible to return it for a replacement?
?
73
?
Andrew
?

Sent: Tuesday, November 18, 2014 12:25 PM
Subject: Re: [loopantennas] Re: AOR LA800
?
?

Hello Andrew

When I first installed the AOR the noise floor was very high around -40 dBM, I put this down to the fact I had the aerial mounted close to the house because of the "short" control cable. When I shut down most of the house electrics the noise dropped to around -83 dBM. My standard 1530 loop mounted 55 ft from the house has -98 dBM in normal operation. The 1010 loop will actually be better than that, but the 1530 is a better comparision for the AOR.

My radio with no antenna connected shows -130 dBM with all the house electrics on.

I then mounted a second 1530 alongside the AOR and had readings of -83 dBM ( AOR ) & -90 dBM ( Welbrook ) I did use a number of ferrite choke cores on the AOR but they made no difference.

The tuning of the AOR is very very sharp, which is fine IF you know the frequency you want if not it's a real pain. The preset frequency ranges given by the control box are ok, with an option to use the antenna in broadband mode which I found to be useless. I was told that the AOR uses a series of band pass / cut off filters to achive it's "tuning" , if that is correct then they work reasonably well.

Because of the very sharp tunning I did not find IMD to be an issue, but then if the antenna is deaf IMD is automatically less of an issue.

Remember that the control cable supplies power to the antenna and with no power the antenna will not function at all, I do not complain about that, but I was unable to discover if a longer control cable is available or the wiring configuration of the cable ( supplied by Buffalo ). So a longer control cable might be a challenge, unless you cut and splice.

Compared to the 1530 the AOR was seriously deaf, so bad was it I thought I had an installation problem and double checked my work.

I have a couple of very experienced ham radio enthusiasts near me, who know more about aerials than I ever will and I invited them over to see if my findings were correct. They were as surprised at just how bad the AOR was, I say again perhaps I had a bad unit.

Given that the AOR is deaf right out of the box, then having to mount the aerial within the electrical field of the house because of the short control cable makes the aerial unusable. I must repeat again that perhaps I had a bad unit, I do hope I did because this is not the sort of product I would expect from AOR let alone for the very high UK price.

This is just my personal experience of the AOR.

Kind regards

Stephen


Locked Re: AOR LA800

 

Hello Andrew

When I first installed the AOR the noise floor was very high around -40 dBM, I put this down to the fact I had the aerial mounted close to the house because of the "short" control cable. When I shut down most of the house electrics the noise dropped to around -83 dBM. My standard 1530 loop mounted 55 ft from the house has -98 dBM in normal operation. The 1010 loop will actually be better than that, but the 1530 is a better comparision for the AOR.

My radio with no antenna connected shows -130 dBM with all the house electrics on.

I then mounted a second 1530 alongside the AOR and had readings of -83 dBM ( AOR ) & -90 dBM ( Welbrook ) I did use a number of ferrite choke cores on the AOR but they made no difference.

The tuning of the AOR is very very sharp, which is fine IF you know the frequency you want if not it's a real pain. The preset frequency ranges given by the control box are ok, with an option to use the antenna in broadband mode which I found to be useless. I was told that the AOR uses a series of band pass / cut off filters to achive it's "tuning" , if that is correct then they work reasonably well.

Because of the very sharp tunning I did not find IMD to be an issue, but then if the antenna is deaf IMD is automatically less of an issue.

Remember that the control cable supplies power to the antenna and with no power the antenna will not function at all, I do not complain about that, but I was unable to discover if a longer control cable is available or the wiring configuration of the cable ( supplied by Buffalo ). So a longer control cable might be a challenge, unless you cut and splice.

Compared to the 1530 the AOR was seriously deaf, so bad was it I thought I had an installation problem and double checked my work.

I have a couple of very experienced ham radio enthusiasts near me, who know more about aerials than I ever will and I invited them over to see if my findings were correct. They were as surprised at just how bad the AOR was, I say again perhaps I had a bad unit.

Given that the AOR is deaf right out of the box, then having to mount the aerial within the electrical field of the house because of the short control cable makes the aerial unusable. I must repeat again that perhaps I had a bad unit, I do hope I did because this is not the sort of product I would expect from AOR let alone for the very high UK price.

This is just my personal experience of the AOR.

Kind regards

Stephen


Locked Re: AOR LA800

 

¿ªÔÆÌåÓý

Stephen,
?
Can you expand on what is wrong with the AOR loop i.e is it low sensitivity, poor local noise rejection or high IMD.
Or is it pain to keep tuning it!!
?
73
?
Andrew Ikin
?

Sent: Tuesday, November 18, 2014 6:25 AM
Subject: [loopantennas] Re: AOR LA800
?
?

Hello

For those who may be interested, I have now had the chance to try this aerial.

The good news is that it is well made, the bad news is that is dreadful.
I compared it against the 7 other loop antennas I have, of which 4 are commercial, and it was the worst of the lot by a long long way.

I cannot understand AOR producing this expensive and very poorly performing antenna, perhaps I had a duff unit.

The Wellbrook or Pixel are much better at 1/3rd the cost of the AOR ( UK prices )

I cannot think why anybody would want to buy the AOR, but be aware that the control cable is only 33ft in length, this means it is unlikely you would be able to mount the aerial far enough away from the electrical field of noise created by your house / shack.

In my case I have to mount all loops a minimum of 50ft from the house which meant for my tests I had to shutdown 90% +? of the house electrics? to create a similar environment.

This post is for general information only, AOR have done good things over the years but this aerial is not one of them.

Regards to all

Stephen


Locked Re: AOR LA800

 

Hello

For those who may be interested, I have now had the chance to try this aerial.

The good news is that it is well made, the bad news is that is dreadful.
I compared it against the 7 other loop antennas I have, of which 4 are commercial, and it was the worst of the lot by a long long way.

I cannot understand AOR producing this expensive and very poorly performing antenna, perhaps I had a duff unit.

The Wellbrook or Pixel are much better at 1/3rd the cost of the AOR ( UK prices )

I cannot think why anybody would want to buy the AOR, but be aware that the control cable is only 33ft in length, this means it is unlikely you would be able to mount the aerial far enough away from the electrical field of noise created by your house / shack.

In my case I have to mount all loops a minimum of 50ft from the house which meant for my tests I had to shutdown 90% +? of the house electrics? to create a similar environment.

This post is for general information only, AOR have done good things over the years but this aerial is not one of them.

Regards to all

Stephen


Locked Re: Foxhole set and such....

 

I know it's a 7 year old post but just in?case?mhatlau is still on the list... and if one of you knows how to contact him please forward this to him - thanks.

I am writing a book about improvised radios built by servicemen in the field, mostly during WWII but also before and after. The stories of the soldiers, sailors and marines and their experiences are all tied to the thread of the ¡°foxhole¡± radios they built. I¡¯ve interviewed many veterans and their families and am past the research stage but I still occasionally check old sources in case I missed anything. I was very happy to stumble on an old news group post of yours that mentions a foxhole radio constructed by your uncle. It¡¯s one of the few I¡¯ve run across built in the Pacific (most were built in Italy) so naturally I¡¯d love to hear more of the story. Do you happen to have a picture of it? Not many exist of the original sets, and I only know of one ¨C possibly two ¨C that were brought back. - brian bcarusella at gmail dot com



Locked Re: Drake AL-4 Loop Antenna

 

Sometime AL4 was used like coupled coil for a large loop antenna.You could change time costant of SPR4 AGC changing value of condenser as stated in manual. I have 2 SPR4 and are my funniest radios; better than my "serious" Collins and EKD's.

Ciao


Locked Re: small loops phasing with 2 channel Afedri SDR and Linrad adaptive beamforming

 

Alan...It is called a small loop because its size is small relative to
one wavelength on the frequency of operation.


Regards.Steve VE9SF


On 11/9/2014 8:51 PM, 'Silverfox' alan.r.hill@... [loopantennas]
wrote:
If that is small, I wonder what large is?

73,

Alan - W6ARH





From: loopantennas@... [mailto:loopantennas@...]
Sent: Sunday, November 9, 2014 12:20 AM
To: loopantennas@...
Subject: Re: [loopantennas] small loops phasing with 2 channel Afedri SDR and Linrad adaptive beamforming





Andrew,



the circumference of the loops is aprroximately 12 meters. Distance between them about 9 meters.

The setup is neither broadside nor endfire, just a random temporary location close to a building.



The pattern is completely unpredictable because of proximity o metal objects. But the smart software did it job and found a null to cancel the noise.



Regards



Piotr, SP2BPD



_____

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2015.0.5315 / Virus Database: 4189/8533 - Release Date: 11/08/14


Locked Re: small loops phasing with 2 channel Afedri SDR and Linrad adaptive beamforming

 

¿ªÔÆÌåÓý

If that is small, I wonder what large is?

73,

Alan - W6ARH

?

?

From: loopantennas@... [mailto:loopantennas@...]
Sent: Sunday, November 9, 2014 12:20 AM
To: loopantennas@...
Subject: Re: [loopantennas] small loops phasing with 2 channel Afedri SDR and Linrad adaptive beamforming

?

?

Andrew,

?

the circumference of the loops is aprroximately 12 meters. Distance between them about 9 meters.

The setup is neither ?broadside nor endfire, just a random temporary location close to a building.

?

The pattern is completely unpredictable because of proximity o metal objects. But the smart software did it job and found a null to cancel the noise.

?

Regards

?

Piotr, SP2BPD


No virus found in this message.
Checked by AVG -
Version: 2015.0.5315 / Virus Database: 4189/8533 - Release Date: 11/08/14


Locked Re: small loops phasing with 2 channel Afedri SDR and Linrad adaptive beamforming

 

Andrew,

the circumference of the loops is aprroximately 12 meters. Distance between them about 9 meters.
The setup is neither ?broadside nor endfire, just a random temporary location close to a building.

The pattern is completely unpredictable because of proximity o metal objects. But the smart software did it job and found a null to cancel the noise.

Regards

Piotr, SP2BPD