Re: The Southern CCrane SWP Slider


Hi Gary...

Well, actually, I originally bought the PL-380 - not to chase TPs, but so that in the daytime (via groundwave of course) I could listen to some domestic out-of-town stations (and a few out-of-state - the Colorado River is about 129.5 miles east of me at its closest point) which my previous radio could not hear at all, not only because I was at or past Radio-Locator's 0.15mV/m contour, but also because in many cases there was a station 10kHz away that bled just as loudly 50-80kHz away, and could still be heard faintly almost halfway across the band (usually worse on the high side than on the low side).

Also, I find it very interesting that my Panasonic RQ-SW20, the radio I was referring to above as my previous radio (which I think has selectivity comparable to the Sony SRF-M37) pulled in some stations quite well near a couple transmitter sites that the PL-380 struggled with or didn't hear at all, in spite of the 380's superior sensitivity and selectivity. For example, here's some comparison recordings - - made about 70-75 feet or so from 1kW KFSD-1450's tower, and there are some comparisons included in this link - - at a location 700 feet from one of the 7 towers of diplexers 5kW KECR-910 and 50kW KCBQ-1170.

Although, like I said, I originally wasn't planning to chase TPs... I did get a little adventurous a few weeks ago, and did manage to record a few in the vicinity of local sunrise toward the end of last month. You've heard and helped confirm a couple of the recordings already.
I will say that using the SAT DEFINITELY helps with the local pests, especially if you can position it right. For example.... I'd like to know your opinion of this recording of JOUB-774 - - that I recorded last month. I cut it so that mostly the stronger signals are in there. That was recorded somewhere around 6:40 to 6:55pm or so, after local radio sunrise. (Translation: in September, local stations were switching to their daytime facilities at 6:30am in San Diego, CA.) As it may be apparent in the filename, I actually saw a reading of 28,17 at least once on that station, and it could have even gone higher, I don't remember. The Select-A-Tenna did a very good job of taming the nearby local pest, KFMB-760, who is 7.3 miles north/northwest from me at a heading of 320°. Also, it helped that KFMB was on their 5kW omnidirectional daytime power at the time. During the day, KFMB comes in at around 66,25 or so on the G8 (pegs the meter at 63,25 on my PL-380), and when it's not TP reception time, shows about 32,00 or 34,00 on 747 and 774 kHz. At night, KFMB's directional 50kW signal has a lobe in my direction, and regularly hits 77,25 on the G8, and 43,00 on 747 and 774 kHz. In a couple places, for example on top of my upright piano, I actually get readings of 81,25 on 760, and 49,00 on 747 and 774. If I combine the Select-A-Tenna with the power pole at the street out front (I've found the powerline seems to inductively couple as if it was a very high gain, but broadband, longwire antenna), I get a 98,25 reading with a sound like and 50,00 from about 153kHz to around 3MHz or so.
However, even with KFMB's killer signal at my location at night, I think reception of TPs on 747 and 774 kHz may be possible. Do you hear anything identifiable in these two recordings?
In checking the recordings myself, I think I hear what I now know to be JOUB in the 774 recording about 3 and a half minutes into it. I'm having a little more difficulty with the 747kHz recording, though. I do hear the soft mute cutting in and out quite a bit, which to me seems to indicate that something's there, but I think it would help if more expert ears (than mine) could discern whether I'm actually hearing a TP on 747, or splatter from 760, 750 or IBOC 740. I should mention those last two recordings were made before 6:30am on Sept 23, when KFMB-760 was still using its nighttime 50kW facility.

--- In ultralightdx@..., D1028Gary@... wrote:

Hi Stephen,

To be honest, despite your apparent impressions, the PL-380 (and the other
Si4734 chip based ULR's) actually have above average AM-band overload
resistance among the Ultralight radio class. The reason for my conclusion is
detailed testing with various ULR's inductively coupled to the 9' PVC loop,
which will seriously overload any pocket radio which is not "crunch
resistant." The 9' loop overloads the analog design Ultralights (SRF-39FP, R9012,
R911, etc.) so badly that whenever the radio is brought within inductive
coupling range of the loop, the loop's tuning capacitor can actually tune the
radio from 530-1700 kHz (regardless of where the radio's tuning capacitor is

The SWP Slider model has outstanding resistance to overload, which makes
it ideal for use with the 9' loop. In this respect, it's probably a shade
more impressive than the Si4734 models. The fact that the SWP Slider has its
own tunable loopstick contributes to this stability, and when the tunable
Slider loopstick is combined with the 9' loop's tuning capacitor, the
ultimate selectivity of the system is probably close to optimum in the Ultralight

Anyway, Stephen, even though there are no more SWP Sliders being made,
it's always possible to boost up your TP-chasing ability by going with a
larger tuned passive loop (than your SAT), or with a 7.5" loopstick PL-380
(which can partially null out some of your pests, if their bearing is about 90
degrees off of the NW direction). The only way you will know which TP's are
possible in your "RF Zoo" is to get up early, and try chasing them before
sunrise. Nobody has a perfect location, or a perfect radio. The most
successful TP-DXers (or TA DXers) are the ones who push their luck constantly, no
matter what handicaps they may face. Optimism, persistence and
determination are the main ingredients for success-- even if your radio, antenna or
location has some limitations. Keep trying, and I'm sure that you will
receive many more TP's this season.

73, Gary

In a message dated 10/18/2010 10:42:54 P.M. Pacific Daylight Time,
pianoplayer88key@... writes:

CQ CQ Calling N7EKX...

I'd be interested in finding out how they compare with separating a very
strong signal from a very weak one (even if it is 10kHz away) when nulling
the strong signal isn't an option. With my PL-380, even in the 1kHz mode, I
can hear some of my strong locals 12kHz away. Across town I was trying to
listen to KDIS-1110 yesterday on my way to a Bible study service.
Unfortunately, their faint 41/00 signal was being stepped on by residual
chirps/chatter from XEPRS-1090, which was booming in at a solid 63/25. (I didn't have
the G8 with me, but I would guess XEPRS probably would have been around
72-76/25 or thereabouts.) However, I was almost right on KDIS's 2mV/m "local"
contour according to Radio-Locator, or possibly just slightly outside it at
the time, in Ocean Beach (a few miles northwest of San Diego airport). When
I have been in rural areas, though, I've been able to get listenable audio
on weaker signals, including some for which I was well outside Radio-Locat
or's estimated 0.15mV/m "fringe" contour - in a few cases even twice as
far, maybe more.
I was wondering how well the Slider+Murata'ed SWP would do in a test which
my PL-380, even in 1kHz BW mode, fails miserably. In a place where (I'm
guessing, as I don't own one to know its actual sensitivity) the PL-360 would
be indicating somewhere around 93/25 to 96/25 WITHOUT an antenna plugged
in... how well would the SWP (and if you want to check it with your
7.5-inched PL-380 (mine's stock) that's fine too) hear a signal 10kHz away coming
from the same direction as the strong pest, for which you are about 1.5 to
2x past Radio-Locator's predicted 0.15mV/m "fringe" contour? My PL-380
utterly fails that test. If it passed it, I'd be able to hear one of the
stations I originally wanted to be able to hear in the daytime, KERN-1180
Wasco-Greenacres, CA, for which I'm about 2x past the 0.15mV/m contour.
Unfortunately, KCBQ-1170's 77/25 signal still has significant splatter audible on 1180
(which does die out by around 1182 or 1183 or so), and even KXMX Anaheim
's 43/00 signal is only barely audible.

73... Stephen (No, I haven't gone past the no-turning-back point and
gotten a Ham license.)

--- In _ultralightdx@... (mailto:ultralightdx@...)
, D1028Gary@ wrote:

Hi Rick,

Thanks for your generous comments on the SWP Slider models. Only about 5
of these models were ever made (in cooperation with Steve Ratzlaff, who
installed the Murata CFJ455K5 filters), including the one that I am
using for TP-DXing each morning. Far more Eton E100 Slider models were
and sent out, including several by John Bryant (with his plywood frame
mounting style).

When the first Si4734 chip 1 kHz DSP model (the Kchibo D96L) was
in August of last year, there was intense interest in whether or not the
model's stock 1 kHz DSP selectivity would be competitive with the
Murata CFJ455K5 IF filters transplanted into our modified SWP and E100
That month I took a new Kchibo D96L to a famous Pacific beach DXpedition
site here in Washington state (Grayland), and made comparison MP3's
the reception of two South Pacific stations. A 3' portable PVC loop was
used to boost signals, and the SWP was tuned 1 kHz off the DX station's
frequency (away from domestic splatter) to provide crisper audio (this
could not
be done with the D96L, because of the "soft mute" issue). In the first
seconds, the D96L (with its 1 kHz Si4734 DSP filtering) receives the
Pacific split-frequency station, and in the last 15 seconds the SWP
(with a Murata CFJ455K5 filter) receives the same signal:

567-2YA Wellington, New Zealand 1250 UTC 8-9-09
( (_
( )

738-Tahiti Mahina, Tahiti 1215 UTC 8-9-09
( (_
( )

Of course the receivers' audio sections also influenced the quality of
received signals, but at the time I reported to the group that the
D96L's 1
kHz DSP selectivity (from its Si4734 chip) was fairly competitive with
that provided by the transplanted Murata K filter in the SWP. The
among the group, however, was that the Murata filter SWP had somewhat
"mellow" audio than that provided by the Si4734 chip's 1 kHz DSP
The Si4734 chip's 1 kHz DSP filtering is a tremendous breakthrough for
inexpensive stock Ultralights, though, and I've used both the 7.5"
PL-380 and the 7.5" loopstick SWP Slider for South Pacific DXpeditions
past summer.

73, Gary DeBock (in Puyallup, WA)

In a message dated 10/18/2010 8:13:45 A.M. Pacific Daylight Time,
w4dst@ writes:

My Thanks to Gary for the CCrane SWP Slider that is now a fine
addition to my shack. Now that it is DXing season, I hope to be able to
give it a good workout with some new DX and hopefully some TA loggings.
I have been comparing it to some of the other receivers in the shack and
I thought I'd pass along my observations. These are not scientific,
just objective but I've tried to be impartial. Some of the results are

One of my receivers is a Sangean ATS-803A that I picked up at a hamfest
over the Labor Day weekend and have given it a good alignment. The
ATS-803A/Radio Shack DX-440 and the Sony 2010 were considered 2 of the
best MW radios of their day and are still excellent performers. I am
fortunate to own both and thought I'd see how the slider stood up to
these 2 classics. My 2010 has 2 Kiwa filters in it, the CCrane has a
2.5kHz MuRata 6 element ceramic filter replacing the stock filter and
the Sangean has both stock filters. Selectivity wise, the CCrane's
MuRata filter is even better than the narrow Kiwa filter in the Sony,
which was surprising, and as good as, or better than the Sangean narrow
filter. The filters in the Sangean surprised me at how good they are
and the audio in the Sangean easily beats the others hands down.

When testing the sensitivity during the day, the slider came out the
winner over both receivers due the nice job Gary did on the slider
antenna. Being able to tune the antenna to the receiver is a very
valuable asset for DXing as others have noted. The Sangean, Sony and
the slider ferrite bars are all very close in length, 7.5" and all are
wound in much the same method with the windings closely wound on the
left end as you face the bar. The slider is slightly better than the
Sangean in nulling and equal to the Sony.

The only radio I have that takes on the slider and comes out ahead in
any way is my classic Radio Shack 12-655. This is a TRF design from the
early 1980s with a similar size ferrite bar. It is a analog radio, very
simple in operation and is legendary in MW DXing circles for its
outstanding sensitivity and nulling ability. During the day, I can
twist and turn my 12-655 and completely null out local WHKP 1450 6 miles
away, and hear WATA in Boone, NC, 140 miles to my north with full
audio. No other radio or my Quanum loop antenna is capable of this,
only my antenna phasing system can duplicate this feat. I have no
idea what contributes to it's amazing nulling quality since the antenna
looks to be wound just like the other 3 bars. As we say in the QRP
community, the 12-655 just has mojo. The slider and the 12-655 are very
close in sensitivity and it would be difficult without test equipment
measurements to determine which is the more sensitive. My 12-655 has
always been my benchmark for sensitivity and nulling capabilities and
will continue to be.

I have also experimented with a 280uH fixed coil ferrite bar antenna
that I wound on a 20cm, 7 7/8", bar from a junked Grundig S350L. It
has a 1/8" stereo plug on the end to interface with my PL-310 with its
"Laurie" mod. It and the slider seem to be equal in sensitivity.
However, the digital filter in the Si4734 has the edge on the MuRata
filter in the CCRane. Once again, I am impressed with Scott and the
rest of the folks at Silicon Labs and the design of this fantastic
chip. It's amazing so much can be packed into this tiny chip.

Good DXing in the upcoming season to everyone.

Rick W4DST
Hendersonville, NC

Join to automatically receive all group messages.