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Old 04-07-2012, 11:03   #1
tpreitzel
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Low Cost Wideband or Tunable Magnetic Loop Antennas

I'm still waiting for a lower cost, i.e. ~ $200, wide band magnetic loop antenna. AFAIK, at this time, 4 options exist for considerably MORE expensive magnetic loops:

1. Wellbrook's ALA-1530 (ships from UK)
2. Pixel Technologies' PRO 1B (ships from US)
3. MFJ Enterprises' MFJ-1786/1788 (ships from US)
4. AOR's LA-400 (ships worldwide)
Others even at $500?

Hopefully, the Chinese will pick-up this task of cranking out lower cost, but good quality wide band magnetic loops. ... I'm STILL waiting.

Last edited by tpreitzel : 23-07-2012 at 09:28.
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Old 04-07-2012, 12:59   #2
mvs sarma
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Quote:
Originally Posted by tpreitzel
I'm still waiting for a lower cost, i.e. ~ $250, wide band magnetic loop antenna. AFAIK, at this time, 3 options exist for considerably MORE expensive magnetic loops:

1. Wellbrook's ALA-1530 (ships from UK)
2. Pixel Technologies' PRO 1B (ships from US)
3. MFJ Enterprises' MFJ-1786/1788 (ships from US)

Others even at $500?

Hopefully, the Chinese will pick-up this task of cranking out lower cost, but good quality wide band magnetic loops. ... I'm STILL waiting.


can you try instead the PA0RDT active mini patch antenna? herer we can adopt a 500cm size rod antenna instead of patch like telescopic.

i used one for quite long lime and it works well. i dont say it gives voltage gain, but it provides enough current gain
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Old 04-07-2012, 18:31   #3
tpreitzel
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Quote:
Originally Posted by mvs sarma
can you try instead the PA0RDT active mini patch antenna? herer we can adopt a 500cm size rod antenna instead of patch like telescopic.

i used one for quite long lime and it works well. i dont say it gives voltage gain, but it provides enough current gain

Unfortunately, I don't have the time, tools, nor territory to build equipment. Even my brief alterations to Degen's 1103 were too time consuming. Unless someone has Roelof's design implemented in hardware for SALE, I'll have to settle for something else.
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Old 06-07-2012, 08:53   #4
tpreitzel
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Has anyone tried PK's loop antennas?

www.amradioantennas.com

I'm specifically looking at their A-Loop-SW620 for ~ $155 USD without shipping...

Last edited by tpreitzel : 06-07-2012 at 08:56.
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Old 08-07-2012, 06:51   #5
tpreitzel
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Although not a loop in the sense of my original post, readers in the USA might find this alternative antenna workable for receivers like Newstar's DR111. One can buy this unit assembled at the factory with a ferrite coiled with 70 turns for the AM broadcast band. One would only have to recoil the ferrite using 7 turns instead of 70 to allow a tunable frequency range ~ 5.5 MHz to 19 MHz which should work very nicely with most DRM broadcasts. Naturally, one could use more turns for working lower frequencies on the SM100 since this unit also allows for the use of an external antenna, e.g. a long wire for upper frequencies. Personally, the frequency range from 5.5 MHz to 19 Mhz is nearly perfect for my needs. One could also buy Ramsey's Signal Magnet in the form of a kit as well. Amazon sells both Ramsey's kit and pre-assembled versions so check CAREFULLY before buying.

Assembled for AM Broadcast band, not SW:

http://www.amazon.com/Ramsey-SM100WT...pd_sim_sbs_e_7

Kit:

http://www.amazon.com/Ramsey-SM100-S...d_rhf_dp_p_t_1

Last edited by tpreitzel : 08-07-2012 at 07:45.
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Old 11-07-2012, 14:46   #6
ianf
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I have ordered a PK Loop, the same model, I will report back
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Old 12-07-2012, 12:46   #7
Mikey
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Quote:
Originally Posted by tpreitzel
Has anyone tried PK's loop antennas?

www.amradioantennas.com

I'm specifically looking at their A-Loop-SW620 for ~ $155 USD without shipping...

Yes I bought one a couple of years ago. On 6 MHz it is ok but not spectacular when compared with something like a Sony AN LP 1. However on AM even here you will usually find that it filters out noise very effectively.As you go higher up the spectrum performance does improve very noticeably on AM. On DRM all I can say is that when using my NEWSTAR DR111 on every frequency including 49 meter band it usually adds at least one bar to the SNR/Signal Strength meter when compared to all of my other active antennas. One thing I would flag up this that although a 9 volt battery works ok, if you increase power to 12v or above it will extend the coverage of the antenna. At 9volts on mine performance drops off part way through the 16 meter band. Up the voltage to 12 or 15 volts and coverage goes to 18 MHz and beyond

Their MW land LW loops are also very effective though more expensive than the Chinese Alternative. The medium wave loop is literally twice the price of the TECSUN. But I still maintain that the improved performance makes it worth every penny.
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Old 12-07-2012, 17:07   #8
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Mikey thanks for this its very useful
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Old 04-07-2012, 17:12   #9
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This is a subject I'm interested in, I use the Degen MS31, or a long wire, the Degen quite good
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Old 06-08-2012, 16:49   #10
ianf
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This antenna is certailnly better than the Degen, which I suppose its cost reflects. Its well made, and high frequency performance is certainly improved by using a 12V battery in place of the 9V one.
Its marginally better at 6Mhz , but at 9Mhz etc its really good, its easier to 'peak' having a wider peak. I think its also better at noise rejection, I often get decoded audio on 1 bar SNR on the Newstar rather than requiring 2 on the Degen. Delivery is quick from Australia too, paying via PayPal.
Its helped me listen to more stations than I have picked up before, in the 9-11-12 Mhz bands.
I will give more updates as I learn more
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Old 07-01-2013, 06:57   #11
tpreitzel
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Yeah, I've been looking at the 6-18 MHz version of PK Loop's SW antenna, but the manual tuning presents a problem for occasional use outdoors. I also looked very closely at AOR's new LA-400 and simply drooled over it, but never seriously considered purchasing it for ~ $550 from Universal Radio. Since I live in a colder climate where SW reception degrades significantly from Oct 15 through Mar 15, I've decided on purchasing Pixel Pro's RF-1B. The RF-1B is currently being sold for delivery in the continental USA with "free" shipping, i.e. no additional cost over the $450, yes $450, price for the antenna with 50' of quad-shielded RG-6 cable.... <sigh> ...

I'm quite sure the results will be worth the price.... I repeat. Your average SWL is NOT going to spend $450 on an outdoor antenna to listen to DRM broadcasts. I sometimes wonder if I could buy Wellbrook's ALA-1530 series antenna and have it shipped to the USA cheaper than spending $450 for the RF-1B, though.

Last edited by tpreitzel : 07-01-2013 at 07:53.
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Old 07-01-2013, 07:28   #12
tpreitzel
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Quote:
Originally Posted by ianf
This antenna is certailnly better than the Degen, which I suppose its cost reflects. Its well made, and high frequency performance is certainly improved by using a 12V battery in place of the 9V one.
Its marginally better at 6Mhz , but at 9Mhz etc its really good, its easier to 'peak' having a wider peak. I think its also better at noise rejection, I often get decoded audio on 1 bar SNR on the Newstar rather than requiring 2 on the Degen. Delivery is quick from Australia too, paying via PayPal.
Its helped me listen to more stations than I have picked up before, in the 9-11-12 Mhz bands.
I will give more updates as I learn more

Since you're selling Newstar's DR111 on Amazon in the UK, I wonder if PK Loop would be open to reselling their standard frequency (6-18 MHz) SW loop in the UK since it's apparently a good match for the DR111. Seriously, the retail price of these magnetic loop antennas needs to be under $200 generally.

Last edited by tpreitzel : 07-01-2013 at 08:23.
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Old 07-01-2013, 12:08   #13
tpreitzel
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Disregard post #17. At the last minute, I chickened out because I really don't want to spend $450 to primarily listen to DRM broadcasts. Instead, I decided to first try Miracle Antenna's MMDs31 physically end-fed, but electrically center-fed dipole. Yes, an experienced amateur can probably build an equivalent antenna for a fraction of the cost. Personally, my time is more expensive than the $120 to ship this antenna to me. Yes, by the time I'm done tinkering around with less capable antennas, I'll still probably finish my journey through antenna land by spending the $450 for a magnetic loop anyway. But before I do, I'll probably spend $200 for LF Engineering's H-900 if the MMDs31 doesn't do any adequate job.

I'm moving these explorations in non-magnetic loop antennas into other threads, though.
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Old 11-01-2013, 17:57   #14
ianf
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I could approach PK to see if he is interested, and see if the pricing would work,
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Old 05-06-2014, 17:28   #15
tpreitzel
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I feel the time is approaching when I'll likely buy Pixel Pro's RF-1B. I've examined closely the major options in antennas. Amplified antennas have their place as do dipoles, but general coverage, wide-band magnetic loops have the greatest flexibility. I need AM's capability of utilizing skywave at night with the ability to null the sheer number of interfering stations... with thanks to the FCC. Can you sense the sarcasm? LF Engineering's H-800 works very well as a general coverage, amplified antenna, but its omni-directional capability is a hindrance with the sheer number of MW stations operating on the same frequency. Frankly, if the work of regulatory bodies were confined to minimizing interference, an omni-directional antenna such as the H-800 would be the cheapest solution. With the current mess on AM, a SWL/DXer needs a highly directional antenna on a rotor. Dipoles require adequate height and space and are restricted to certain bands.

To new SWLs, bite the financial bullet and buy a wide-band magnetic loop. Both Wellbrook and Pixel Pro sell excellent models. Currently, expect to spend $500.

To manufacturers, I expect a decent market exists for a good general coverage, wide-band magnetic loop at a retail price of <= $250. $125 sounds reasonable for parts and labor to assemble such an antenna.

Last edited by tpreitzel : 09-06-2014 at 07:56.
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