|
Re: Thai Score
Joe
Gary,
I am in the process of gathering materials to build the 3 " FSL antenna, I am just wondering where you can buy the Oatey 4x4 foam closet spacers? |
|
|
|
Re: Thai Score
David Henry
Hi Gary,
Great stuff!! Just to add that I had a surprise visit from this station on 28 February 2016 at 22:31 UTC here in Aberdeen, Scotland. I have been testing my new SANGEAN DT-250 and I was sitting on a very busy 1575 kHz in the late evening when suddenly in the midst of the mayhem came the familiar VOA 'Yankee Doodle' sig tune, followed by the VOA voice ID in English. A new programme then started in an UNID language and then quickly faded down never to return. I was assuming it would have been from the Sao Thome transmitter, but Allen Willie pointed out that on 1575 it is from Thailand! Pretty amazing for barefoot! So far, I am really liking the DT-250. Selectivity could be better, but it is streets ahead of my SONY SRF T-615 in that respect and it has given me a heap more pest-free channels. Cheers, David Henry Aberdeen, Scotland. |
|
|
|
Re: Puyallup, WA Ultralight TP's for 3-2
Hi Mark,
Thanks for your comments, and analysis of the challenge in reproducing acceptable audio with high-Q tuned circuits.
Actually the new, hard-wired FSL antennas have provided much better DX station audio than expected, even in the narrowest (1 kHz DSP) filter selection in the Tecsun PL-380 model. The stark difference in DX station audio fidelity between the hard-wired FSL's and the inductively coupled FSL's has been one of the greatest surprises of the entire experimentation, along with the unusually sharp nulling capability of the hard-wired FSL's. My guess is that the razor-sharp, high-Q tuning system of the inductively coupled FSL's will always have the side effect of cutting off high frequency audio response, similar to the old ceramic filters like the Murata CFJ455K5 (which we used to transplant into the 455 kHz IF Ultralights like the Eton E100 and C.Crane SWP, before Tecsun introduced the Si4734 DSP chips in their pocket radios).
Generally speaking, unless a DXer lives in an ideal location such as Newfoundland (or other isolated ocean coast location), high transoceanic DX station audio fidelity is pretty much a luxury that doesn't exist in the pocket radio class, although the new hard-wired FSL antennas come as close as possible in meeting the challenge. Their unique combination of sensitivity and DX station audio fidelity (with 1 kHz DSP filtering) is unprecedented.
73 ,Gary DeBock (in Puyallup, WA, USA)
-----Original Message-----
From: mdh@... [ultralightdx] <ultralightdx@...> To: ultralightdx Sent: Thu, Mar 3, 2016 4:46 am Subject: Re: [ultralightdx] Puyallup, WA Ultralight TP's for 3-2 Hey Gary;
First, compliments on your continued testing and "how to's" for FSL's. I continue to follow along, in part to enjoy your excellent work! Regarding audio frequency response w/ the same type of antenna coupled two different ways to a radio. Several years ago I notice the same phenomenon using the CCrane Twin Ferrite and coupling it either direct or via an inductive winding. I'm an audio engineer first, but an RF guy a distant third so I do not know these answers for certain. However, I have had several years to think about the coupling question and have decided for RF, we may be seeing something similar to what audio ppl started discovering in the 70's .... choice of transformers and capacitors do make a difference in the sound of audio. This is why "direct-coupled" or 'DC' circuits (as they were often marketed) became popular. Over the years quality transformers and capacitors have found their way back into hi-end audio circuits - they do provide benefits and do not degrade 'sonics' if of proper quality (specs). Switching back to coupling FSL to radio ... My best guesses are: (a) There could be an impedance mismatch or a 'circuit effect' that is acting as a low pass filter when doing inductive coupling. Or (b) do you know the rolloff specs of the digital filters? If they are gradual - for instance, you are using a 1khz filter but if the skirts are say 30db/ as opp to 60db/ at overload - and the direct-coupled antenna is pushing more signal strength into the radio, in effect that will give you a wider RF bandwidth and therefore wider audio frequency range. AM audio is a favorite subject but I am forever in the "learning" mode so if anyone thinks differently, please speak up! Regards, Mark |
|
|
|
Thai Score
The attached photo is from the predawn reception of 1575-VOA (Ban Phachi, Thailand) on the "barefoot" 3 inch FSL Tecsun PL-380 Ultralight here in Puyallup, WA, USA this morning. The lady is speaking in Burmese, according to the VOA ID heard at 1430 UTC.
Fairly common on west coast table receivers and large external antennas during the fall season, at 7,329 miles (11,795 km) the station isn't common at all on hand-held portables at inland west coast locations in the month of March.
73 and Good DX,
Gary DeBock (in Puyallup, WA, USA)
"Science Fiction PL-380" barefoot
|
|
|
|
Re: Newfoundland Ultralight Radio Logs March 2-3
Rik
I am REALLY impressed by your logging OREGON from far eastern Canada! Was that barefoot too? - FARMERIK
|
|
|
|
Re: Newfoundland Ultralight Radio Logs March 2-3
Paul Juarez
Nice! 😊 Thank you Allen for the DX reports. On Mar 3, 2016 1:23 PM, "vo1_001_swl@... [ultralightdx]" <ultralightdx@...> wrote:
|
|
|
|
Newfoundland Ultralight Radio Logs March 2-3
Allen Willie
Hello To All, It's been a good week here in the North Atlantic with 4 new additions to the Ultralight radio logbook including Oregon for USA State # 43 heard on Ultralight radio. 1350 khz - WEZS - Laconia, New Hampshire 1:55 UTC 3/2/16 w/ Election primaries talk, then into ads, "Newstalk 1350 WEZS " ID, Fox News and Fox News Radio ID , weather for the Lakes Region, then back into talk show ( signal in the clear then mixing with CKAD Nova Scotia ) Ultralight Station # 1344
Ultralight Station # 1345 1530 khz - WVBF - Middleborough , Massachusetts 23:00 UTC 3/2/16 w/ weather Forecast, mention of Massachusetts , ID and mention of other associated stations, then into talk about Trump , situation in Libya , then talk about EU and economics // tunein(dotcom) web audio feed Ultralight Station # 1346 1640 khz - KDZR - Lake Oswego, OREGON 7:15 UTC 3/3/16 w/ Talk show with discussion about the Free Masons, then into "Portland's Home For Talk, Talk 16-40", Ad for Gresham Ford, "News, Talk, Business... Talk 1640" ID Heard coming through weak to fair during WTNI - Mississippi signal fades
Good DX to All,
|
|
|
|
Re: Micro BOG?
Rik
I spent a lot of time looking into this and my conclusion is it may well be worth running a BOG as short as 100 to 250 feet for MW to get a low noise antenna. That is very different than what I found online before I started using 500 foot BOGs. By the way, back when I switched from a temporary SE to a permanent ENE, only about 60-70 degrees different in bearing, it changed the transatlantic broadcast stations I heard nearly completely on LW. The BOGs were both 500 feet or 150m and the part of LW I heard broadcasters from is 1500-2000m so they were less than 1/10th wave length. Thanks to all who helped me on this journey. I hope to hear of others getting good results with micro BOGs.- FARMERIK
|
|
|
|
Puyallup, WA Ultralight TP's for 3-3
It was another productive morning for Asian signals, with the Japanese big
guns on 594, 693, 747 and 828 once again managing very good signals in and out
from 1400-1445. In addition there was a fair low-band presence of Chinese
signals on 603 and 639, along with a decent appearance of 1575-VOA around
1430.
My session started at 1410 with very good Japanese signals on 594 and 747,
along with a similar signal in and out from 972-HLCA (although nowhere near
yesterday's awesome level). 603 was all China here this morning, reaching a fair
level around 1435 along with a poor to fair signal from 639-CNR1. The CRI
stations on 1017 and 1044 also managed ghostly levels in and out, but were
nothing to shout about. 1575-VOA was strong enough at 1430 to manage a decent ID
on the 3" FSL Tecsun PL-380, while both 1566-HLAZ and 1593-CNR1 stayed at
underperforming levels all morning. Overall the session was similar to
yesterday's as far as the NHK big gun strength, although there was more of a
Chinese presence on other frequencies than yesterday's Korean orientation. Best
Asian signal of the session was from 594-JOAK at 1433, reaching a brief
excellent level with Japanese conversation.
603 China Hulun Buir? Chinese female speech with fair peaks around
1435
1575 VOA Ban Rasom, Thailand Burmese female speech at fair to good
level at 1433 (recorded on the
"barefoot" 3" FSL Tecsun PL-380)
73 and Good DX,
Gary DeBock (in Puyallup, WA, USA)
7.5" loopstick CC Skywave Ultralight +
15" FSL antenna
|
|
|
|
Re: Puyallup, WA Ultralight TP's for 3-2
Mark/airchecklover
Hey Gary;
First, compliments on your continued testing and "how to's" for FSL's. I continue to follow along, in part to enjoy your excellent work! Regarding audio frequency response w/ the same type of antenna coupled two different ways to a radio. Several years ago I notice the same phenomenon using the CCrane Twin Ferrite and coupling it either direct or via an inductive winding. I'm an audio engineer first, but an RF guy a distant third so I do not know these answers for certain. However, I have had several years to think about the coupling question and have decided for RF, we may be seeing something similar to what audio ppl started discovering in the 70's .... choice of transformers and capacitors do make a difference in the sound of audio. This is why "direct-coupled" or 'DC' circuits (as they were often marketed) became popular. Over the years quality transformers and capacitors have found their way back into hi-end audio circuits - they do provide benefits and do not degrade 'sonics' if of proper quality (specs). Switching back to coupling FSL to radio ... My best guesses are: (a) There could be an impedance mismatch or a 'circuit effect' that is acting as a low pass filter when doing inductive coupling. Or (b) do you know the rolloff specs of the digital filters? If they are gradual - for instance, you are using a 1khz filter but if the skirts are say 30db/ as opp to 60db/ at overload - and the direct-coupled antenna is pushing more signal strength into the radio, in effect that will give you a wider RF bandwidth and therefore wider audio frequency range. AM audio is a favorite subject but I am forever in the "learning" mode so if anyone thinks differently, please speak up! Regards, Mark |
|
|
|
Re: Quick question about the latest FSL antennas for the PL-380
<<< One more question (yeah, right, surely this can't be the last :-) ): For any given diameter and/or ferrite bar length, how do you know how many turns of the 250/46 Litz wire to use? >>>
Hi Again Chris,
Whenever a new inductively coupled FSL antenna is designed it is always necessary to find the number of coil turns necessary for complete MW band coverage (530-1700 kHz). When the initial FSL antenna model is completed it is a process of trial and error to adjust the number of coil turns, in search of the optimal MW band coverage.
For the new, hard-wired FSL's the process is much easier-- simply measure the coil inductance of the first FSL test model and make sure that it is within the recommended limits of the PL-380's Si4734 DSP chip (180-450 uH). As long as the inductance of the first FSL test model is in the middle of this range you then have some leeway in adding and subtracting coil turns for the sake of convenience, since the inductance would still be within acceptable limits. If you wish to maintain the same inductance with a larger coil, simple mathematical formulas are used to calculate the new number of coil turns. The mathematical value of "Pi" (3.141) is used very frequently in FSL design, especially to determine the number of ferrite rods necessary to build the large monster loops while the designs are still on the drawing board.
73, Gary DeBock (in Puyallup, WA, USA)
-----Original Message----- From: ku4a@... [ultralightdx] To: ultralightdx Sent: Wed, Mar 2, 2016 5:40 am Subject: Re: [ultralightdx] Quick question about the latest FSL antennas for the PL-380 Thanks, Gary. That information is a huge help. We will think about whether or not to contact you about the 100 mm ferrite bars.
One more question (yeah, right, surely this can't be the last :-) ): For any given diameter and/or ferrite bar length, how do you know how many turns of the 250/46 Litz wire to use?
73
Chris
KU4A
|
|
|
|
Re: Puyallup, WA Ultralight TP's for 3-2
Michael <michael.setaazul@...>
On 03.03.16 02:50, D1028Gary@... [ultralightdx] wrote:
<<< Very well done.. And the audio quality is a lot better. >>>... I agree with you about the audio. For some unknown reason, the------------------------------------------------------ This sounds much like my observation with a single long tuned ferrite on LW, inductively coupled to the radio. Tuning is very sharp, so bandwidth is narrowed, cutting off higher audio frequencies. As it is manually tuned, one can move the passband across the receive frequency and thereby "recover" the higher audio frequencies on either the usb or lsb. With a PL380 the integral tuning will counteract this. Hardwiring the FSL into the frontend will load the tuning coil more than inductive coupling and thereby widen the passband. Michael |
|
|
|
Re: Puyallup, WA Ultralight TP's for 3-2
<<< Very well done.. And the audio quality is a lot better. >>>
Thanks for your comment, Derek!
I agree with you about the audio. For some unknown reason, the hard-wired FSL antennas seem to provide much better audio quality in the PL-380 (using the 1 kHz DSP setting) than the inductively-coupled FSL's, which tend to clip off the higher audio frequencies when they provide a signal boost. It's one more fringe benefit of these new little DX chasers.
73, Gary
-----Original Message----- From: Derek Vincent mw12voltdx@... [ultralightdx] To: ultralightdx Sent: Wed, Mar 2, 2016 3:46 pm Subject: Re: [ultralightdx] Puyallup, WA Ultralight TP's for 3-2
|
|
|
|
Re: Puyallup, WA Ultralight TP's for 3-2
Derek Vincent
On Mar 2, 2016, at 8:54 AM, "D1028Gary@... [ultralightdx]" <ultralightdx@...> wrote:
|
|
|
|
Puyallup, WA Ultralight TP's for 3-2
Very good Asian conditions prevailed during sunrise enhancement this
morning, with an awesome S9 signal from 972-HLCA around 1415 as the star
attraction. 594-JOAK, 693-JOAB, 747-JOIB, 828-JOBB and 1566-HLAZ all managed
good signals from 1400-1440, while the KBS2 parallels on 558 and 603 reached
fair levels in and out.
The S9+ recording of 972-HLCA linked below was made on the "barefoot" 3"
FSL Tecsun PL-380 Ultralight at 1415. A photo of the "Science Fiction PL-380"
making this recording of HLCA during the pre-sunrise darkness is posted at https://app.box.com/s/3jelpflsiug7ojkx140tyj5k953y6o3c
972-HLCA Korean pop music at awesome level at 1415; best Asian signal of
the session
73 and Good DX,
Gary DeBock (in Puyallup, WA, USA)
"Barefoot" 3" FSL Tecsun PL-380 Ultralight
|
|
|
|
Re: Quick question about the latest FSL antennas for the PL-380
ku4a@...
Thanks, Gary. That information is a huge help. We will think about whether or not to contact you about the 100 mm ferrite bars.
One more question (yeah, right, surely this can't be the last :-) ): For any given diameter and/or ferrite bar length, how do you know how many turns of the 250/46 Litz wire to use? 73 Chris KU4A |
|
|
|
Re: ForSale: Flex 6500/Flex 6300/ Elecraft K3/P3 & Elecraft KX3.//
M. K.
I suspect everyone on this list already knows this, but just in case... The above message is an attempt to SCAM people out of their money....On Wed, Mar 2, 2016 at 12:07 AM, larry_rj73@... [ultralightdx] <ultralightdx@...> wrote:
|
|
|
|
ForSale: Flex 6500/Flex 6300/ Elecraft K3/P3 & Elecraft KX3.//
larry_rj73@...
Price: '/. |
|
|
|
Re: Quick question about the latest FSL antennas for the PL-380
Hi Chris,
<<< Is it possible to build the 3-inch FSL with the "common" ferrite bars? If so, it would probably require 20 or less, and we have the pool noodle on hand. If we HAVE to go to the 4.25-inch FSL, then we need more "common" ferrite bars, and a bigger pool noodle. >>>
Yes, Chris, there is already a 3" FSL PL-380 version made with 15 of the common 62mm ferrite bars, for which I've attached a photo. Nobody except for me has built one of these yet, however, and construction information hasn't been published yet. Its DXing performance is better than the 7.5" loopstick PL-380 models, but not quite up to the standard of the original 3" 100m bar FSL version, or the 4.25" 62 mm bar FSL version. There is a "sensitivity rating" system to judge the performance of FSL designs, by the way (coil diameter x ferrite length). This 3" 62mm bar version has a rating of 186, while the original 3" 100mm version has a rating of 300. The 4.25" 62mm (Pest Control) version has a rating of 264.
<<< I can imagine that there are performance difference between the two. But either one will be a great antenna for us. So, in summary, am wondering if the 3-inch FSL can be built with the 62 X 12 X 4 ferrite bars. >>>
Actually, Chris, if you (and/or your friend) would really prefer to build the original 3" FSL version with the 100mm bars, I may be able to help you out. There is a very high demand for these bars and they are no longer available on eBay, but they do exist. Please contact me by private email if you would prefer this option.
73, Gary DeBock (in Puyallup, WA, USA)
-----Original Message----- From: ku4a@... [ultralightdx] To: ultralightdx Sent: Tue, Mar 1, 2016 1:52 pm Subject: [ultralightdx] Quick question about the latest FSL antennas for the PL-380 A friend of mine and I here have started pulling together the parts needed for the FSL antennas. We both have PL-380s.
I have downloaded construction articles for the 3-inch and 4.25-inch FSLs. On hand, we have the 2-inch pool noodle (fits the 3-inch FSL) and 20 of the "common" ferrite bars (62mm X 12mm X 4mm) (22 required for the 4.25-inch FSL). We also have a good quantity of 250/46 Litz wire, and have already done some "practice" tinning/soldering.
Is it possible to build the 3-inch FSL with the "common" ferrite bars? If so, it would probably require 20 or less, and we have the pool noodle on hand. If we HAVE to go to the 4.25-inch FSL, then we need more "common" ferrite bars, and a bigger pool noodle.
I can imagine that there are performance difference between the two. But either one will
be a great antenna for us. So, in summary, am wondering if the 3-inch FSL can be built with the 62 X 12 X 4 ferrite bars.
Thanks!
Chris
KU4A
|
|
|
|
Re: Micro BOG?
Rik
Thanks. Very good info there I think, but way over my head. I did hear from N4DJ and he answered questions. - Thanks FARMERIK
|
|
|