Date   

Re: FSL's: Relative strength based on size.....

Gary DeBock
 

Hi Dave,

<<<   This is probably a question for Gary. I am trying to get a feel for how much better a 12"-15" FSL is compared to my 4 1/4: and 7" FSL's. I have used your comparative formula, but was wondering what I won't hear, for example, at the Coast with mine vs your big FSL's. Can you put that into a db difference? I am thinking that because of the very low noise level of FSL's, it is more about signal volume of weaker signals, rather than hearing or not hearing something at all.   >>>

In general the FSL sensitivity design formula (coil diameter x ferrite length = relative sensitivity) works well for design purposes, but it doesn't accurately predict signal advantages in dB's.

The best way to judge signal advantages is to simultaneously record two concurrent MP3's using identical portables inductively coupled to two different FSL antennas, while having all other factors equalized between the two setups (antenna height, direction, tuning accuracy, etc.). Then after the initial recording switch the antennas, and see if anything changes in relative signal strength.

On the ocean coast the 17" FSL can typically receive a weak DU station at around an S5 level, while an 8" FSL can receive the same DU station at around an S3 level. The 3.5" Baby FSL can receive enough of the same DU station to make sure of the identity, but the signal will only be around the S1 level (barely audible).

DU propagation is usually far more important than the size of the FSL antenna in producing overall results. The strongest signal I've ever received from a Western Australian station (and also the strongest recording that I've ever heard made from W.A. by anybody here on the west coast) was 558-6WA, received on an 8" FSL antenna on an ocean side hill in Lincoln City, Oregon during a solar eclipse trip last year. The 17" FSL has received W.A. 5 times at the Rockwork cliff, but never like that  https://dreamcrafts.box.com/s/pihnpq1bb676w92g19yb5bxoe1s30wpr

<<<   Last fall I had my 7" FSL at the Coast near Newport and clearly heard Arabic voice and MX on 1611 and 1701 from the ethnic Aussie stations which are 400 watts or less, so it seems to be big enough for anything out there. Any comments from Gary and others?   >>>

Yes, if superb DU propagation is on your side, a 7" FSL is more than adequate to run really wild on the ocean coast, receiving almost anything that any other antenna could pull in at Cape Perpetua, Rockwork or any other enhanced coastal site. It's only when conditions are marginal that you may wish for something larger-- but in that case you will probably only end up with a few "Big Gun" DU's anyway. If conditions are superb the 17" FSL may receive a DU at an S9 level while your 7" FSL would have the same station at an S6 level, but most DXers wouldn't care about that.

<<<   By the way, I have conducted several thorough tests with both my FSL's and a Quantum loop. Both FSL's beat the Q uantum hands down in S/N all across MW. The smaller FSL doesn't always have the signal level of the Quantum, but weaker signals are much clearer. I have run the test with the Q turned up to narrow the Quantum bandwidth and quiet the background noise and still the FSL's sound better. This is no dig against the Quantum since it is still one of the best loops of it's type. The FSL's are passive which makes them so quiet and that makes a big difference.   >>>

Yes, the passive FSL's usually do have a S/N advantage over the Quantum, and other active loops. Even the 3.5" Baby FSL's (a.k.a. "Frequent Flyers") can really run wild on isolated ocean beaches, far away from any RFI sources. The biggest thrill in my lifelong hobby was taking one of these tiny FSL's to the Cook Islands in April, and tracking down multiple exotic MW stations (India, Mongolia, etc.) that had never been heard in Grayland (at closer range) since DXers first started going there. FSL antennas really are game changers when somebody gives them half a chance.

73, Gary DeBock (in Puyallup, WA, USA)

             


-----Original Message-----
From: daiche@... [ultralightdx]
To: ultralightdx
Sent: Thu, Sep 20, 2018 1:25 pm
Subject: [ultralightdx] FSL's: Relative strength based on size.....

 
This is probably a question for Gary. I am trying to get a feel for how much better a 12"-15" FSL is compared to my 4 1/4: and 7" FSL's. I have used your comparative formula, but was wondering what I won't hear, for example, at the Coast with mine vs your big FSL's. Can you put that into a db difference? I am thinking that because of the very low noise level of FSL's, it is more about signal volume of weaker signals, rather than hearing or not hearing something at all.

Last fall I had my 7" FSL at the Coast near Newport and clearly heard Arabic voice and MX on 1611 and 1701 from the ethnic Aussie stations which are 400 watts or less, so it seems to be big enough for anything out there. Any comments from Gary and others?

By the way, I have conducted several thorough tests with both my FSL's and a Quantum loop. Both FSL's beat the Q uantum hands down in S/N all across MW. The smaller FSL doesn't always have the signal level of the Quantum, but weaker signals are much clearer. I have run the test with the Q turned up to narrow the Quantum bandwidth and quiet the background noise and still the FSL's sound better. This is no dig against the Quantum since it is still one of the best loops of it's type. The FSL's are passive which makes them so quiet and that makes a big difference.

Dave Aichelman     N7NZH     Grants Pass, Oregon


Re: WMVP is quiet on 1000 KHz.

Rik
 

WMVP back to full power. RSSI=7718 on Eton Trav Exec. - FARMERIK


WMVP is quiet on 1000 KHz.

Rik
 

This comes in well here on my Westerly BOG, and there are not too many stations on 1000 KHz so a good freq to try this evening. -FARMERIK



FSL's: Relative strength based on size.....

daiche
 

This is probably a question for Gary. I am trying to get a feel for how much better a 12"-15" FSL is compared to my 4 1/4: and 7" FSL's. I have used your comparative formula, but was wondering what I won't hear, for example, at the Coast with mine vs your big FSL's. Can you put that into a db difference? I am thinking that because of the very low noise level of FSL's, it is more about signal volume of weaker signals, rather than hearing or not hearing something at all.


Last fall I had my 7" FSL at the Coast near Newport and clearly heard Arabic voice and MX on 1611 and 1701 from the ethnic Aussie stations which are 400 watts or less, so it seems to be big enough for anything out there. Any comments from Gary and others?


By the way, I have conducted several thorough tests with both my FSL's and a Quantum loop. Both FSL's beat the Quantum hands down in S/N all across MW. The smaller FSL doesn't always have the signal level of the Quantum, but weaker signals are much clearer. I have run the test with the Q turned up to narrow the Quantum bandwidth and quiet the background noise and still the FSL's sound better. This is no dig against the Quantum since it is still one of the best loops of it's type. The FSL's are passive which makes them so quiet and that makes a big difference.


Dave Aichelman     N7NZH     Grants Pass, Oregon


Re: Try Something New This DX Season!

Rik
 

Gary-

Thanks for bringing together your articles in one post. I wish they all were in the files here. From my Connecticut location, I don't plan any Trans Pacific DXing, but the equipment you build could be used here. It looks to me you ordinarily inductively couple portables with longer ferrite antennas attached to your FSL loops.

Continuing to experiment with things I can build/buy  and DX from home-FARMERIK


Re: Try Something New This DX Season!

Paul Blundell
 

Thanks for sharing this Gary.
I am looking forward to becoming more involved in the hobby again.
Paul


Sent from my Samsung GALAXY S5

-------- Original message --------
From: "D1028Gary@... [ultralightdx]" <ultralightdx@...>
Date: 20/09/2018 7:00 PM (GMT+10:00)
To: ultralightdx@...
Subject: [ultralightdx] Try Something New This DX Season!


 










Hello All,



One of the reasons why our Ultralightdx Yahoo group has had strong growth for ten years is because we have accepted many diverse challenges... from the basic challenge of DXing with a simple pocket radio (which all of us share) all the way up to the challenge of developing 21st Century antennas and discovering innovative DXing sites-- to make pocket radios surprisingly effective in Transoceanic DXing results.



Not all of us have the ability or desire to develop breakthrough antennas or perform loopstick transplant operations, but the entire history of the Ultralight Radio DXing community has been one of pioneering accomplishments-- from Rob Ross' reception of 300 stations in one month on his SRF-59, Richard Allen's reception of multiple Longwave TA's from Europe and Africa on his 7.5" loopstick PL-360 in Oklahoma, and Allen Willie's reception of hundreds of TA's on his SRF-M37V in Newfoundland. When our late Co-Founder John Bryant was still with us he would constantly challenge each one of the Ultralightdx leaders (including me) to try something new-- either in antenna work, DXing accomplishments or volunteer service.


John was an ex-Professor of Architecture at Oklahoma State University in Stillwater, and he had a natural teaching style familiar to all those who knew him. John was the one who introduced me to DU-DXing in 2008, teaching me all the basics of how to track down exotic South Pacific DX right in the middle of the worst possible season-- the dog days of summer. At the time it sounded like science fiction to me, and I thought that John might be "pulling my leg--" but he was absolutely right!


I don't have anywhere near the accomplishments or leadership that John had, but he and I did share a fascination with antennas-- especially monster antennas that could make Ultralight radios highly competitive in Transoceanic DXing. So, in the spirit of John Bryant, I would like to offer some links to articles that have inspired many Ultralight Radio DXers (and others) to really push the limits in antenna construction-- including one article that John and I wrote together. As I have shared with anyone willing to listen, I'm convinced that the future of our Ultralight Radio community is very bright-- and optimism and innovation will win out over pessimism and boredom every time. Sometime this winter, why not try something new to increase your DXing fun-- maybe a new antenna, a new band (FM, SW or Longwave) or Transoceanic DX reception? The future belongs to those who are excited about it-- one of the reasons why our Ultralight Radio Community has been one of the most vibrant segments of the AM-DXing community for ten years!


73 and Good DX,


Gary DeBock (in Puyallup, WA, USA)


Ultralight Radio Group Co-Founder






1)  Supercharging the Sony ICF-2010 (May 2008)



Using the loopstick transplant principles developed through extensive Ultralight radio experimentation, this article details how to replace the ICF-2010's stock 6.5" loopstick with a 19.5" composite transplant, thereby dramatically boosting MW band sensitivity (while providing a significant boost to Longwave reception as well).



http://www.mediafire.com/file/3msq1yx6hn7tm5g/SuperchargingtheICF2010LargeComplete.pdf


2)  E100 Slider Loopstick (September 2008)


Co-authored with John Bryant, this article explains how to replace the E100 stock loopstick with a far more effective 7.5" Slider loopstick. Many of these highly sensitive models are still in DXing service today


http://www.mediafire.com/view/nqggfm2jymc/YOU_CAN_DO_THIS_Building_the_Slider_E100.pdf


3)  PVC Loops-- The Low Cost Ticket to High DX Gain (August 2009)


Tired of expensive commercial antennas or pricey ferrite sleeve loops? This article will teach you how to build a dirt-cheap PVC air core loop with side sizes from 18 inches up to 9 feet... all of them (MW models) costing well under $100. The 9' monster size loop was used here to receive 7 Medium Wave TA's in 2009-2010.



http://www.mediafire.com/file/0bpbmda7lnhdy6p/PVCLoop-LCTtoHDXG-Article.doc/file



4)  PL-360 Plug-in 7.5" Loopsticks  (June 2010)


Do you have a PL-360 model (with its plug-in antenna jack for AM and LW loopsticks)? This article will teach you how to replace the deaf midget loopstick with extremely effective 7.5" Medium Wave and Longwave plug-in replacements-- with no modification required to the radio at all. 25 of the MW and 5 of the LW plug-in loopsticks were made here and sent out to PL-360 owners-- many of which are still in use.


http://www.mediafire.com/view/2cqwsqj0bvajf6k/7.5%20inch-LS.doc


5)  7.5" Longwave Loopsticks  (June 2011)


Detailed technical article describing the challenge and success in developing 7.5" Longwave-optimized loopsticks for the Tecsun DSP Ultralights. Includes basic instructions for building your own 7.5" Longwave loopstick PL-380 model


http://www.mediafire.com/view/845snah2h4ek9z9/7.5inLWLS.doc


6)  7" FSL Antenna-- Detailed "Heathkit-like" Construction Article (October 2011)


Build your own 7" Ferrite Sleeve Loop antenna at a cost of under $200. This detailed article has multiple Photoshop-enhanced instructional photos to guide you in creating a highly effective 7" FSL antenna


http://www.mediafire.com/view/dshnqlbydf6qu25/7%20Inch%20Diameter.doc


7)  5" FSL Antenna-- Detailed "Heathkit-like" Construction Article (March 2012)


Build your own 5" Ferrite Sleeve Loop antenna at a cost of under $150. This detailed article has multiple Photoshop-enhanced instructional photos to guide you in creating a highly effective 5" FSL antenna


http://www.mediafire.com/view/9ze98h293s85p86/5%20inch%20FSL.doc


8)  Supercharging the PL-380-- Detailed "Heathkit-like" Construction Article (October 2013)


Replace the midget stock loopstick in your Tecsun PL-380 with a far more effective 7.5" Medium Wave or Longwave loopstick transplant-- and enjoy a new level of DXing success. Multiple Photoshop-enhanced assembly photos to guide you in the process of creating your own highly sensitive DXing portable-- for under $100 in assembly parts.


http://www.mediafire.com/view/du3sr5cd9thqvau/7.5inch-LS-PL380.doc


9)  3 inch FSL Tecsun PL-380-- Detailed "Heathkit-like" Construction article (January 2016)


Replace the midget stock loopstick in your Tecsun PL-380 with a compact, lightweight 3" FSL antenna-- externally mounted and optimized for high-level Medium Wave DXing excitement . Multiple Photoshop-enhanced assembly photos guide you in the assembly process.


http://www.mediafire.com/file/w0gcek56f6aq7kr/3_Inch_FSL_Tecsun_PL.doc


10)  3.5 inch (89mm) "Frequent Flyer" FSL Antenna-- Detailed "Heathkit-like" Construction article (July 2017)



Specifically designed to routinely pass through airport security checkpoints and provide high-gain inductive coupling boosts for MW-DXing portables, the "Frequent Flyer" FSL's have already been used in Asia, Africa, Europe, North America and Hawaii for some exceptional DXing fun. Several of the MP3's recorded in Kona, Hawaii have assisted DXers in North America and Japan to make sure of receptions such as 621-Tuvalu and 1440-Kiribati. The detailed article uses multiple Photoshop-enhanced assembly photos to guide you in the construction process- all for about $150 in commonly available parts.




http://www.mediafire.com/file/pnfm8909c77zjoy/3.5inch-FF-FSL.doc

11)  Supercharging the XHDATA D-808 AM-LW-FM-SW-AIR SSB Portable (September 2018)

Although the XHDATA D-808 is not an Ultralight Radio, it is a very sensitive AM-DXing portable that can be transformed into a dream AM or Longwave DX-chasing travel radio. It can also be used as an SSB "spotting receiver" on ocean beaches, to track the carrier strength of exotic DX stations for Ultralight Radio reception. "Supercharge" your D-808 with this detailed, illustrated article-- containing 20 pages of clear instructions to guide you in the process!  http://www.mediafire.com/file/t2989hg61vbkb5h/Supercharging_the_XHDATA_D_-808-FinalMWLW.doc/file


Re: Try Something New This DX Season!

Gary DeBock
 

Thanks Michael,

Your comments are appreciated. 

But I guess one of the side effects of having a surplus of enthusiasm is a reluctance to go to sleep at a decent hour, as multiple future antenna projects compete for a few minutes of testing time. It's very fortunate that other DXers don't suffer from this strange quirk (my reluctant analysis, as I type this at 0258 PDT).

73, Gary
 



-----Original Message-----
From: Michael michael.setaazul@... [ultralightdx]
To: ultralightdx
Sent: Thu, Sep 20, 2018 2:17 am
Subject: Re: [ultralightdx] Try Something New This DX Season!

 
Inspiring input, Gary!
Autum is a good time to look through such
articles and consider what to try in the
winter months.

Thanks for keeping us curious and active!

Michael UK

On 20.09.18 10:00, D1028Gary@... [ultralightdx] wrote:
> Hello All,
> One of the reasons why our Ultralightdx Yahoo group has had
> strong growth for ten years is because we have accepted many diverse
> challenges...
.......
> So, in the spirit of John Bryant, I would like to
> offer some links to articles that have inspired many Ultralight Radio
> DXers (and others) to really push the limits in antenna construction--
> including one article that John and I wrote together
....


Re: Try Something New This DX Season!

Michael <michael.setaazul@...>
 

Inspiring input, Gary!
Autum is a good time to look through such
articles and consider what to try in the
winter months.

Thanks for keeping us curious and active!

Michael UK

On 20.09.18 10:00, D1028Gary@... [ultralightdx] wrote:
Hello All,
One of the reasons why our Ultralightdx Yahoo group has had strong growth for ten years is because we have accepted many diverse challenges...
......
So, in the spirit of John Bryant, I would like to offer some links to articles that have inspired many Ultralight Radio DXers (and others) to really push the limits in antenna construction--
including one article that John and I wrote together
...


Try Something New This DX Season!

Gary DeBock
 

Hello All,

One of the reasons why our Ultralightdx Yahoo group has had strong growth for ten years is because we have accepted many diverse challenges... from the basic challenge of DXing with a simple pocket radio (which all of us share) all the way up to the challenge of developing 21st Century antennas and discovering innovative DXing sites-- to make pocket radios surprisingly effective in Transoceanic DXing results.

Not all of us have the ability or desire to develop breakthrough antennas or perform loopstick transplant operations, but the entire history of the Ultralight Radio DXing community has been one of pioneering accomplishments-- from Rob Ross' reception of 300 stations in one month on his SRF-59, Richard Allen's reception of multiple Longwave TA's from Europe and Africa on his 7.5" loopstick PL-360 in Oklahoma, and Allen Willie's reception of hundreds of TA's on his SRF-M37V in Newfoundland. When our late Co-Founder John Bryant was still with us he would constantly challenge each one of the Ultralightdx leaders (including me) to try something new-- either in antenna work, DXing accomplishments or volunteer service.

John was an ex-Professor of Architecture at Oklahoma State University in Stillwater, and he had a natural teaching style familiar to all those who knew him. John was the one who introduced me to DU-DXing in 2008, teaching me all the basics of how to track down exotic South Pacific DX right in the middle of the worst possible season-- the dog days of summer. At the time it sounded like science fiction to me, and I thought that John might be "pulling my leg--" but he was absolutely right!

I don't have anywhere near the accomplishments or leadership that John had, but he and I did share a fascination with antennas-- especially monster antennas that could make Ultralight radios highly competitive in Transoceanic DXing. So, in the spirit of John Bryant, I would like to offer some links to articles that have inspired many Ultralight Radio DXers (and others) to really push the limits in antenna construction-- including one article that John and I wrote together. As I have shared with anyone willing to listen, I'm convinced that the future of our Ultralight Radio community is very bright-- and optimism and innovation will win out over pessimism and boredom every time. Sometime this winter, why not try something new to increase your DXing fun-- maybe a new antenna, a new band (FM, SW or Longwave) or Transoceanic DX reception? The future belongs to those who are excited about it-- one of the reasons why our Ultralight Radio Community has been one of the most vibrant segments of the AM-DXing community for ten years!

73 and Good DX,

Gary DeBock (in Puyallup, WA, USA)

Ultralight Radio Group Co-Founder




1) Supercharging the Sony ICF-2010 (May 2008)


Using the loopstick transplant principles developed through extensive Ultralight radio experimentation, this article details how to replace the ICF-2010's stock 6.5" loopstick with a 19.5" composite transplant, thereby dramatically boosting MW band sensitivity (while providing a significant boost to Longwave reception as well).


http://www.mediafire.com/file/3msq1yx6hn7tm5g/SuperchargingtheICF2010LargeComplete.pdf

2) E100 Slider Loopstick (September 2008)

Co-authored with John Bryant, this article explains how to replace the E100 stock loopstick with a far more effective 7.5" Slider loopstick. Many of these highly sensitive models are still in DXing service today

http://www.mediafire.com/view/nqggfm2jymc/YOU_CAN_DO_THIS_Building_the_Slider_E100.pdf

3) PVC Loops-- The Low Cost Ticket to High DX Gain (August 2009)

Tired of expensive commercial antennas or pricey ferrite sleeve loops? This article will teach you how to build a dirt-cheap PVC air core loop with side sizes from 18 inches up to 9 feet... all of them (MW models) costing well under $100. The 9' monster size loop was used here to receive 7 Medium Wave TA's in 2009-2010.

http://www.mediafire.com/file/0bpbmda7lnhdy6p/PVCLoop-LCTtoHDXG-Article.doc/file

4) PL-360 Plug-in 7.5" Loopsticks (June 2010)

Do you have a PL-360 model (with its plug-in antenna jack for AM and LW loopsticks)? This article will teach you how to replace the deaf midget loopstick with extremely effective 7.5" Medium Wave and Longwave plug-in replacements-- with no modification required to the radio at all. 25 of the MW and 5 of the LW plug-in loopsticks were made here and sent out to PL-360 owners-- many of which are still in use.

http://www.mediafire.com/view/2cqwsqj0bvajf6k/7.5%20inch-LS.doc

5) 7.5" Longwave Loopsticks (June 2011)

Detailed technical article describing the challenge and success in developing 7.5" Longwave-optimized loopsticks for the Tecsun DSP Ultralights. Includes basic instructions for building your own 7.5" Longwave loopstick PL-380 model

http://www.mediafire.com/view/845snah2h4ek9z9/7.5inLWLS.doc

6) 7" FSL Antenna-- Detailed "Heathkit-like" Construction Article (October 2011)

Build your own 7" Ferrite Sleeve Loop antenna at a cost of under $200. This detailed article has multiple Photoshop-enhanced instructional photos to guide you in creating a highly effective 7" FSL antenna

http://www.mediafire.com/view/dshnqlbydf6qu25/7%20Inch%20Diameter.doc

7) 5" FSL Antenna-- Detailed "Heathkit-like" Construction Article (March 2012)

Build your own 5" Ferrite Sleeve Loop antenna at a cost of under $150. This detailed article has multiple Photoshop-enhanced instructional photos to guide you in creating a highly effective 5" FSL antenna

http://www.mediafire.com/view/9ze98h293s85p86/5%20inch%20FSL.doc

8) Supercharging the PL-380-- Detailed "Heathkit-like" Construction Article (October 2013)

Replace the midget stock loopstick in your Tecsun PL-380 with a far more effective 7.5" Medium Wave or Longwave loopstick transplant-- and enjoy a new level of DXing success. Multiple Photoshop-enhanced assembly photos to guide you in the process of creating your own highly sensitive DXing portable-- for under $100 in assembly parts.

http://www.mediafire.com/view/du3sr5cd9thqvau/7.5inch-LS-PL380.doc

9) 3 inch FSL Tecsun PL-380-- Detailed "Heathkit-like" Construction article (January 2016)

Replace the midget stock loopstick in your Tecsun PL-380 with a compact, lightweight 3" FSL antenna-- externally mounted and optimized for high-level Medium Wave DXing excitement . Multiple Photoshop-enhanced assembly photos guide you in the assembly process.

http://www.mediafire.com/file/w0gcek56f6aq7kr/3_Inch_FSL_Tecsun_PL.doc

10) 3.5 inch (89mm) "Frequent Flyer" FSL Antenna-- Detailed "Heathkit-like" Construction article (July 2017)


Specifically designed to routinely pass through airport security checkpoints and provide high-gain inductive coupling boosts for MW-DXing portables, the "Frequent Flyer" FSL's have already been used in Asia, Africa, Europe, North America and Hawaii for some exceptional DXing fun. Several of the MP3's recorded in Kona, Hawaii have assisted DXers in North America and Japan to make sure of receptions such as 621-Tuvalu and 1440-Kiribati. The detailed article uses multiple Photoshop-enhanced assembly photos to guide you in the construction process- all for about $150 in commonly available parts.


http://www.mediafire.com/file/pnfm8909c77zjoy/3.5inch-FF-FSL.doc
11) Supercharging the XHDATA D-808 AM-LW-FM-SW-AIR SSB Portable (September 2018)
Although the XHDATA D-808 is not an Ultralight Radio, it is a very sensitive AM-DXing portable that can be transformed into a dream AM or Longwave DX-chasing travel radio. It can also be used as an SSB "spotting receiver" on ocean beaches, to track the carrier strength of exotic DX stations for Ultralight Radio reception. "Supercharge" your D-808 with this detailed, illustrated article-- containing 20 pages of clear instructions to guide you in the process! http://www.mediafire.com/file/t2989hg61vbkb5h/Supercharging_the_XHDATA_D_-808-FinalMWLW.doc/file


November 2-8 Poipu, Kauai (Hawaii) Ultralight DXpedition

Gary DeBock
 

On the outside chance that another DXer might want to try out his Asian luck at a forward Pacific location this fall, I thought the details of this trip should be posted. My wife and I plan to stay in a beach motel at Poipu Kai, which is the extreme southernmost point of Kauai island (the westernmost of the main Hawaiian islands). The ocean beach point should provide an unobstructed salt water path to Asia, ANZ, North and South America-- although the RF zoo of Oahu will also have an unobstructed path. It remains to be seen how much of a detriment this will be.

     The same "Frequent Flyer" FSL and DXing gear that was used in the Cook Islands this April should be taken on this trip, and this location is on exactly the same longitude as Aitutaki in the Cooks. Although the "Frequent Flyer" FSL and modified CC Skywave are both small enough to easily fit inside hand carry luggage, they tend to act like the ultimate TP-DXing overachievers when surrounded by salt water. India, Bangladesh, Cambodia, Mongolia and Brazil were all received on MW in the Cooks, and I would be happy to supply identical gear to anyone else who wishes to try their luck on Kauai http://www.mediafire.com/file/rcsss62udssl9js/April_2018_Cook_Island_Ultralight_DXpedition-final.docx/file
 Thanks also to Craig Barnes for his pioneering DXpedition to Princeville, Kauai in April of 2017, during which multiple Chinese stations were at an S9 level-- even when recorded on an open air i-Phone video

73, Gary DeBock (in Puyallup, WA, USA)




Re: Ultralight DX on an Airplane?

Phillips
 

Pilots can request retransmissions to ensure understanding.  Besides, pilots are uncanny in their ability to understand voice communications over aircraft radio circuits despite all sorts of interference and distractions.


I spent years working avionics and there is very little that could be affected by a local oscillator.   All I can think of is maybe an AM direction finder.  Aircraft still use LW beacons for airport-status but any receiver tuned to air-ground-air comms would be so far up the spectrum that its local oscillator would be orders of magnitude away from the LW frequency.   As local oscillators are set to frequencies above received frequencies, it is highly unlikely that even a LW local oscillator could get down to a LW beacon.  


Mobile (cell) phones can transmit up to five watts even when not actually making a call.  As would tablets and other SIM-card-equipped  devices.  And they transmit that high power using digital encoding.  I am sure that the 20+Kms of wiring in a modern commercial aircraft would ingest a lot of that power.  How many people turn their phones completely off when in an aircraft?   I'd worry a lot more about digital 5W phones inside a digital aircraft than analogue microwatt superhets.


There are WiFi equipped devices which transmit digital signals in the 2.4GHz or 5.8GHz bands.  They produce only small amounts of power but it is deliberately radiated.   How much of that power is picked up by the aircraft?


Then there are external sources of interference.  Two fly-by-wire Airbus aircraft in the same area over the Indian Ocean to the North West of Australia, have suffered sudden loss of control followed by equally sudden restoration of control.  Someone using their phone......or transmissions from the super-high-power HAARP installation on the West Australian coastline almost directly under the flight path?    Maybe something else.    Fortunately no one suffered serious injury and there have been no recurrences since the two incidents.  Perhaps someone changed procedures or maybe the aircraft have been "hardened".


Eventually it all boils down to how well aircraft are engineered to be impervious to extraneous electronic insult and they are very well engineered indeed.  I don't fly myself (no need to) but I let my wife fly without any qualms, even on the "HAARP route".
 
Ray



From: ultralightdx@... on behalf of Michael michael.setaazul@... [ultralightdx]
Sent: Tuesday, 18 September 2018 3:55 PM
To: ultralightdx@...
Subject: Re: [ultralightdx] Re: Ultralight DX on an Airplane?
 
My understanding was that the original concern was that an oscillator
emitting inside the cabin *might* disrupt pre-digital avionics
- not crew communications. With advances in electronics, this has
been superseded by other concerns.

Michael UK
.............................

On 18.09.18 01:52, ray Phillips phillicom@... [ultralightdx] wrote:
....
> Superhet radio receivers are those that have a local oscillator and can
> emit a radio signal.
....
> The local oscillator signal is small and does not contain any modulation
> and so will not carry any sounds from inside the aircraft.  At worst it
> will generate a fixed tone in the pilots' headsets.
....
> When flying in commercial aircraft, you can be assured that the aircraft
> is totally secure from locally generated interference.
> Ray


------------------------------------

------------------------------------


------------------------------------

Yahoo Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/ultralightdx/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/ultralightdx/join
    (Yahoo! ID required)

<*> To change settings via email:
    ultralightdx-digest@...
    ultralightdx-fullfeatured@...

<*> To unsubscribe from this group, send an email to:
    ultralightdx-unsubscribe@...

<*> Your use of Yahoo Groups is subject to:
    https://info.yahoo.com/legal/us/yahoo/utos/terms/


Re: Ultralight DX on an Airplane?

Rémy Friess
 

You can even use superhets to decode SSB transmissions with a receiver that does not have SSB. You tune one set to the wanted frequency and the other 455 kHz below (provided it is single conversion) then you can use the tuning button as a clarifier (BFO).



De : ray Phillips phillicom@... [ultralightdx]
À : ultralightdx@...
Sujet : Re: [ultralightdx] Re: Ultralight DX on an Airplane?
Date : 18/09/2018 02:52:16 CEST

 

Superhet radio receivers are those that have a local oscillator and can emit a radio signal.  


A quick course in basic superhet theory.

There are two main frequencies at play in a superhet - the tuned frequency and the local oscillator frequency.   The local oscillator is normally set to a frequency above the tuned frequency and the two frequencies "track" each other as the radio is tuned to maintain a constant "difference" frequency.   This difference frequency is called the Intermediate Frequency (IF).   As it is a constant frequency, simple circuit techniques can be used to provide the massive amplification needed.


The local oscillator signal is small and does not contain any modulation and so will not carry any sounds from inside the aircraft.  At worst it will generate a fixed tone in the pilots' headsets.  And then only if a specific (and highly unlikely) arithmetic relationship exists between the aircraft receive frequency and the superhet's receive frequency.  This arithmetic relationship is equal to the IF of the superhet.


About the only time a superhet will generate a tone is when the superhet is tuned to a specific frequency some hundreds of KHz away from the aircraft receive frequency.  If the superhet is tuned to the same frequency as the aircraft, no tones will be generated. 


If the local oscillator is operating outside the aircraft radio's tuning selectivity,  the aircraft tuning circuitry will reject it and so any interfering radio would, not only need to be tuned within a small band of specific frequencies, but be in a location where its miniscule power could enter the aircraft radio circuitry.   


In the days of valve (tube) radios, the local oscillator could make power in the tens to hundreds of milliwatts and be detected over distances of twenty metres (sometimes more).   My first (and highly illegal) transmitter was a modified valve local oscillator circuit connected to an antenna.  It transmitted from the barracks to the car park.  These days, transistor local oscillators make very little power.


When flying in commercial aircraft, you can be assured that the aircraft is totally secure from locally generated interference.  



Here is an experiment if anyone is interested;


Tune one of your sensitive receivers to a vacant frequency above the middle of the AM band.  Turn the volume high.


Get a superhet radio and position it close to the sensitive receiver.  It must be a superhet - look for a group of little square cans on the circuit board.  A cheap one is best because it won't have any screening.


Tune it about 455KHz below the frequency of the sensitive radio. 


Slowly tune the superhet up and down and listen for a whistle or a damping of the static in the sensitive receiver. 


Once (if) you establish a whistle or static damping, move the domestic radio away.  You will find that it is not long before any signs of the local oscillator vanish.   Now you know how far that superhet's local oscillator will transmit - it won't be far.




Ray

 



 



From: ultralightdx@... on behalf of andresperezf@... [ultralightdx]
Sent: Tuesday, 18 September 2018 12:14 AM
To: ultralightdx@...
Subject: [ultralightdx] Re: Ultralight DX on an Airplane?
 
 

Thanks, guys.


One last question... Does listening to the pilots with a receiver, which is not able to transmit, cause any interruption in their communication? If so, I am the first person to stop using listening to them because my life is in danger.

I would understand if the radio was able to transmit, I would not want the pilots to hear noises from the cabin rather than the actual instructions from the tower.


Re: Ultralight DX on an Airplane?

Michael <michael.setaazul@...>
 

My understanding was that the original concern was that an oscillator
emitting inside the cabin *might* disrupt pre-digital avionics
- not crew communications. With advances in electronics, this has
been superseded by other concerns.

Michael UK
............................

On 18.09.18 01:52, ray Phillips phillicom@... [ultralightdx] wrote:
...
Superhet radio receivers are those that have a local oscillator and can emit a radio signal.
...
The local oscillator signal is small and does not contain any modulation and so will not carry any sounds from inside the aircraft. At worst it will generate a fixed tone in the pilots' headsets.
...
When flying in commercial aircraft, you can be assured that the aircraft is totally secure from locally generated interference.
Ray


Re: Ultralight DX on an Airplane?

Phillips
 

Superhet radio receivers are those that have a local oscillator and can emit a radio signal.  


A quick course in basic superhet theory.

There are two main frequencies at play in a superhet - the tuned frequency and the local oscillator frequency.   The local oscillator is normally set to a frequency above the tuned frequency and the two frequencies "track" each other as the radio is tuned to maintain a constant "difference" frequency.   This difference frequency is called the Intermediate Frequency (IF).   As it is a constant frequency, simple circuit techniques can be used to provide the massive amplification needed.


The local oscillator signal is small and does not contain any modulation and so will not carry any sounds from inside the aircraft.  At worst it will generate a fixed tone in the pilots' headsets.  And then only if a specific (and highly unlikely) arithmetic relationship exists between the aircraft receive frequency and the superhet's receive frequency.  This arithmetic relationship is equal to the IF of the superhet.


About the only time a superhet will generate a tone is when the superhet is tuned to a specific frequency some hundreds of KHz away from the aircraft receive frequency.  If the superhet is tuned to the same frequency as the aircraft, no tones will be generated. 


If the local oscillator is operating outside the aircraft radio's tuning selectivity,  the aircraft tuning circuitry will reject it and so any interfering radio would, not only need to be tuned within a small band of specific frequencies, but be in a location where its miniscule power could enter the aircraft radio circuitry.   


In the days of valve (tube) radios, the local oscillator could make power in the tens to hundreds of milliwatts and be detected over distances of twenty metres (sometimes more).   My first (and highly illegal) transmitter was a modified valve local oscillator circuit connected to an antenna.  It transmitted from the barracks to the car park.  These days, transistor local oscillators make very little power.


When flying in commercial aircraft, you can be assured that the aircraft is totally secure from locally generated interference.  



Here is an experiment if anyone is interested;


Tune one of your sensitive receivers to a vacant frequency above the middle of the AM band.  Turn the volume high.


Get a superhet radio and position it close to the sensitive receiver.  It must be a superhet - look for a group of little square cans on the circuit board.  A cheap one is best because it won't have any screening.


Tune it about 455KHz below the frequency of the sensitive radio. 


Slowly tune the superhet up and down and listen for a whistle or a damping of the static in the sensitive receiver. 


Once (if) you establish a whistle or static damping, move the domestic radio away.  You will find that it is not long before any signs of the local oscillator vanish.   Now you know how far that superhet's local oscillator will transmit - it won't be far.




Ray

 



 



From: ultralightdx@... on behalf of andresperezf@... [ultralightdx]
Sent: Tuesday, 18 September 2018 12:14 AM
To: ultralightdx@...
Subject: [ultralightdx] Re: Ultralight DX on an Airplane?
 
 

Thanks, guys.


One last question... Does listening to the pilots with a receiver, which is not able to transmit, cause any interruption in their communication? If so, I am the first person to stop using listening to them because my life is in danger.

I would understand if the radio was able to transmit, I would not want the pilots to hear noises from the cabin rather than the actual instructions from the tower.


Re: Ultralight DX on an Airplane?

Andres Perez
 

Thanks, guys.

One last question... Does listening to the pilots with a receiver, which is not able to transmit, cause any interruption in their communication? If so, I am the first person to stop using listening to them because my life is in danger.

I would understand if the radio was able to transmit, I would not want the pilots to hear noises from the cabin rather than the actual instructions from the tower.


Re: DSP ULR antenna uH values?

Rik
 

I probably got confused. My plan is to experiment and see what happens. I have no education in radio theory.

Nice Web site you have. I have been there many times.  TimeTraveler is where I read about the faster refresh rate for the Eton Trav. RSSI.

- Thanks- FARMERIK


Re: Ultralight DX on an Airplane?

kevin asato <kc6pob@...>
 

Hi Andy,
you can use small electronics during take off and landings. With the exception of WiFi on the planes, most airlines have the In Flight Entertainment (IFE) running gate to gate. Electronics larger than a tablet (computer) are to be stowed on take off and landing as they can become lethal projectiles or interfere with aircraft evacuation. it's already bad enough that there is hardly any room to use your laptop while seated normally on the plane.

Times have changed and electronics has advanced. Still i would not want someone to interfere with VHF voice communications which still relies on AM technology. It's bad enough that i have to get on a plane up to 50 times a year.
73,
kevin
kc6pob



I
have not flown on commercial aircraft in a few years.  But
my recollection was that they still had you turn off all
electronics during take-off and landing -- times when
it's more critical and they want to make absolutely sure
that nothing goes wrong.  Are they still doing this?  I
don't know.


Re: Ultralight DX on an Airplane?

kevin asato <kc6pob@...>
 

it's possible to receive airband radio inflight but i would not. you may actually interfere with the aircraft's capability of receiving necessary communications; not something i want anyone to do when i am flying onboard that particular aircraft. modern aircraft radios are probably more tolerant but why risk it?

as far as your radio is concerned, the radio should not be damaged by the aircraft transmitter. but that is not what i care about.
73,
kevin
kc6pob

One more
question... Is it possible with a portable Airband radio to
listen to communications from the pilots of my plane? I have
heard this could damage the radio because I am very close to
the antenna that transmits the signals.


Re: Exec Traveler vs Skywave & ? -FARMERIK

mediumwavedx
 

I did a first impressions of this radio on my blog back in 2015. As I recall, the display update was quite a bit faster (3 times per second). Also, soft-mute had been turned off. Tuning is very smooth.


Bill


Re: Exec Traveler vs Skywave & ? -FARMERIK

Rik
 

Like you I appreciate the RSSI numbers, but don't like how slow the refresh rate is on the Tecsuns. Have you noticed the refresh rate being faster for RSSI on the Eton ? Mine will be here in a week or so, but this is good info to have in the group messages.

My Skywave SSB has up down buttons for 10 KHz steps as well as a knob. Although 10 KHz steps with the knob seem reliable.  The tuning indicator refreshes often, it has the number 5 as the fifth indicator bar, which helps my tired old eyes. Although not an ULR, the Sangean ATS 405 has an indicator with even more possible bars which is very quick.

Waiting for parts and a radio- FARMERIK


6581 - 6600 of 34094