[IRCA] Questions re: FSL vs PVC loop vs SAT/others
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[IRCA] Questions re: FSL vs PVC loop vs SAT/others



Hi... I was wondering about a few things re: performance of the "affordable" FSL vs the PVC loop vs SAT (and/or maybe a couple other "antennas")...
 
I listened to the shootout recordings of the 7" FSL vs the 4' PVC loop.  I could tell a minor difference in a few of them (with the FSL being marginally better), but in the others I couldn't tell any difference at all.  So how much of an improvement are they over the barefoot ULRs like the SRF-59, PL-380 and PL-606?
 
I compiled a few comparison recordings, linked below.  (Unfortunately my Zoom H2 isn't recognizing SD cards so I'm unable to make new recordings at this time.)
 
 
   830 KLAA - 50kW @ 89 mi:
 
830 KLAA - PL-606 (1k bw) - barefoot "32,25" then with SAT "54,25"
http://www.mediafire.com/?38qkjyo4e3moa5b
 
 
 
    960 KIXW - 5kW @ 122 mi:
 
960 KIXW - PL-606 (1k bw) - barefoot "27,00" then with SAT "34,18"
http://www.mediafire.com/?vm0nxz424pxemp2
 
There's some intermittent static at the beginning of the SAT portion of the recording.  Any idea what this might have been?  It sounds similar to what happens when our clothes dryer is running, but I was something like 150 feet or so away.
 
 
    990 XECL - 5kW @ 84 mi (also may have KTMS in bkgd - 5kW @ 197 mi, DA sends ~12 WATTS(!) toward me):
 
990 XECL - SRF-59 - barefoot then with SAT
http://www.mediafire.com/?xqc1u44qp8r2dd0
 
So how well do the PVCs or FSLs do at pulling in 12 watts from almost 200 miles away around midday? ;)  (Or is it possible that I miscalculated the effect the directional pattern has?  Also something like 80-90% of the path is saltwater.)
 
 
 
    1070 KNX - 50kW @ 111 mi:

1070 KNX - PL-380 (6k bw) - barefoot
http://www.mediafire.com/?qretc5q74onf5vz
1070 KNX - PL-380 (6k bw) - with SAT
http://www.mediafire.com/?h1x4hsxcezsdmlq
1070 KNX - PL-380 (4k bw) - with SAT + chainlink fence - "69-72,25"
http://www.mediafire.com/?tod6q8ddtt22c9l
 
Interestingly, KNX comes in a few dB stronger than KFI here, even thogh the latter is about 12 miles closer.  (BTW would I have any chance at logging that NZ station on 639 kHz?)
 
 
 
    1110 KDIS - 50kW @ 111 mi:

1110 KDIS - SRF-59 - barefoot
http://www.mediafire.com/?9o7sh8gmo19ol2j
1110 KDIS - PL-606 (4k bw) - barefoot - "41,00"
http://www.mediafire.com/?lb2sjynd5yb1c8v
1110 KDIS - PL-606 (2k? bw) - with SAT - "42,25"
http://www.mediafire.com/?98soctilt0b8x53
 
The SRF-59 seems to be better at digging KDIS out than the PL-606, or the PL-380.  It does get a little splash from 1130 KSDO, though - 10 kW at 6.3 miles, reads approximately "74,25" to "76,25" or so on the barefoot PL-606.
 
 
    1190 KGBN - 20kW @ 97 mi:
 
1190 KGBN - PL-606 (1k bw) - barefoot - "43,00"
http://www.mediafire.com/?7oow53rikccw6ga
1190 KGBN - PL-606 (1k bw) - with SAT - "25,12 to 27,08-19"
http://www.mediafire.com/?suqixjsqtgmkks9
1190 KGBN - SRF-59 - barefoot then with SAT
http://www.mediafire.com/?a6p3113p86oubl9
 
Interestingly, KGBN's RSSI was actually LOWER with the SAT than barefoot!  Any idea why this would happen?  (It wouldn't be caused by the local 50kW 1170 KCBQ, would it?  It's 9.3 miles away and reads about "80,25" to "82,25" or so on the barefoot PL-606.)  Also it seems that the SRF-59 did a little better at pulling it in barefoot then the PL-606, especially when nulling 1170.  Facing 1170 splashed KCBQ on top of 1190 on the SRF-59, though.
 
Would alignment of the SRF-59 help peak the sensitivity even more, and prevent KCBQ from splashing on 1190 even when I'm facing 1170's transmitter?  Also would it enable splatter-free reception of 1180 KERN (a station that I heard once at around 1pm on the PL-606, even though I'm about 2x past Radio-Locator's 0.15 mV/m contour, when KCBQ was off the air for a few minutes) around midday even with KCBQ on the air, while still having audio frequency response better than the analog part of an IBOC broadcast (with a signal level comparable to the 1290-KZSB or 1110-KDIS barefoot SRF-59 recordings)?
 
 
    1290 KZSB - 500 watts @ 195 mi:
 
1290 KZSB - PL-380 - with SAT then barefoot
http://www.mediafire.com/?9dlzjtltujg885s
1290 KZSB - PL-606 (1k bw) - barefoot "24,06-10" then with SAT "31,14 - 34,22"
http://www.mediafire.com/?yw6zqn5lm15jqgo
1290 KZSB - SRF-59 - barefoot
http://www.mediafire.com/?b8rhed11vddll6f
 
I noticed the performance of the SRF-59 was very close on sensitivity.  (In some cases I've actually thought the '59 did better than the '606.)  
 
 
 
    1510 KSPA - 10kW @ 100 mi:
 
1510 KSPA - SRF-59 - barefoot
http://www.mediafire.com/?5l5hle13mnn618a
1510 KSPA - PL-606 (4k bw) - barefoot - "30,00"
http://www.mediafire.com/?b8rhed11vddll6f
1510 KSPA - PL-606 - barefoot "24,00" then with SAT "28,10"
http://www.mediafire.com/?b8rhed11vddll6f
 
The small difference in RSSI between barefoto vs. with the SAT is due to what I suspect may be powerline noise.  What I don't know is why would I be picking that noise up from like 100+ feet away?
 
 
 
So how much better is the FSL or the 4' PVC loop than the Select-A-Tenna?  Also at approximately what size (and price) FSL would be the break-even point vs the SAT?  (An "affordable" FSL for me would be somewhere around $20-30 or so - maybe I should consider building a PVC loop instead?  Is there a way to build one that sets up to be larger than the SAT, yet can be dismantled to fit in a backpack?)
 
 
 
Also I've noticed that there's a particular part of a barbed wire fence across the street from my house that enhances LW beacon reception.  Earlier this year I made a recording comparing barefoot reception of 404-MOG on the PL-606 in 1 kHz BW (reading "15,01") with reception on the fence (reading "25,20"):
http://www.mediafire.com/?xv0719a0vyri6xc
Also here's a photo of the PL-606 on the fence.
The most distant NDB I've heard with that setup so far is "BO" from Boise, ID.  (I forget the frequency now or where the recording is.)  It seems to favor north/south reception (and is oriented that direction).  The total length of this fence, not counting any broken sections of wire, is approximately 875 feet.  Interestingly, using a utility pole's ground wire didn't help LW reception at all - all it did was desense the radio.  It DOES give MW a serious boost, especially when "tuned" with the Select-A-Tenna.  For example, I received 50kW 1580 KMIK from 300 miles away one night with the util ground + SAT at a level with which I had to be 90 feet from one of 5kW 1290 KKDD's towers around midday to get the same strength barefoot.  Also the same setup boosts 760 KFMB (50kW nights @ 7.3 miles) to a level for which I have to be within 10 FEET(!) of one of 2.5kW 590 KTIE's towers to get the same level barefoot.  So how much better would the FSL or the
 PVC loop be than the SAT + utility ground combination?  Would it be possible to get the same amount of boost with one, while preventing overload/desense/splatter (depending on the radio used) on the strong locals?
 
A couple questions...  How much better would the LW FSL or LW PVC loop perform than the fence?  Also, since it wasn't originally intended to function as an antenna, and isn't tuned, would using the fence still count as "barefoot"?
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