Re: [IRCA] Oregon Cliff Ultralight DU's for 7-20
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Re: [IRCA] Oregon Cliff Ultralight DU's for 7-20



Hi Gary,

Interesting reading your reports, as always.  I hope you're recording videos of some of your catches and will be posting them soon after returning to Puyallup. :)

I see you often had S/N levels pegging the meter at 25 dB.  Have you had any signals pegging the RSSI meter at 98 dBµ? ;)  I'd think that if you've had stations testing the overload level, maybe you've come close?  (I've noticed that when the RSSI goes above about 94-95 dBµ or so, the audio starts clipping/distorting even when tuned on-frequency, and in more extreme cases will start cutting out, or worse.)

How close have any of those DUs come to being as strong as in these KCBQ videos?  ;)
http://www.youtube.com/watch?v=tE2n94DLDak - this was recorded 9.2 mi S of the station

http://www.youtube.com/watch?v=kEIU3mP5f38

http://www.youtube.com/watch?v=fEMLcEqCu3E


That "Tijuana ESPN noise generator" is a local for me, being around 15-16 miles away to the SSW (which would probably make it a bit tough for me to get that Christian broadcaster on 1701 here ;) ) and indicating around the low 50s dBµ around the clock on the barefoot PL-606 at my house.  I almost wish I would have known to check to see if it was actually off the air, or maybe conditions were preventing your reception of them.  Come to think of it, too, I also think I have heard them sending out just an unmodulated carrier on maybe a couple occasions, but I didn't check them last night / this morning.

I do notice that sometimes it will have audio pumping due to the soft mute engaging, though.  I suspect that maybe that station (as well as XEPRS-1090 which I suspect should be a blowtorch up there if it wasn't for KPTK, KECR-910 and especially XESDD-1030 and XESS-620) pushes the modulation envelope possibly well beyond 100% on peaks.  I've noticed that the higher the modulation peaks, the lower the S/N dB indication is.  I've even had 620 and 1030 read a solid 0 dB S/N for a minute or longer at a stretch when using the 4 kHz bandwidth, even though the RSSI is in the low to upper 40s or so, and they're not close enough to other strong stations to have a 40s RSSI be the result of front-end overload.

Sometime I'd like to try my luck at some early morning TP DXing from a better place than my house.  Problem for me now is, due to motels being over my budget, I'd have to do it close enough so I could go and come back the same day.  I personally would be ok with up to a 2 or 3 hour drive each way.

So, if I was going to do one of those excursions (won't be anytime soon though as I don't have my own car), which would you think would be the lesser of two evils?  Going to the coast, where my radio would be bombarded by all the high-powered signals in southern California that direct, in some cases, hundreds of kW ERP at the ocean (and would have several signals well into the 80s dBµ on barefoot ULRs unless I went past Santa Barbara, which would be probably 4+ hours away)?  Or, going out to the desert (maybe near Salton Sea in Imperial Valley), where I'd be on the back sides of the patterns, but dep ending on where I was, the local ground conductivity may be fairly low?  (It's terrible in Coachella Valley, but is pretty good around Salton Sea, El Centro, etc.)

About that 7.5" loopstick plus 8" FSL ...  how much gain does the combo have over the stock PL-380 that you're using?  If I don't have strong signals nearby, I can often get 50 dBµ gain or so with a Select-A-Tenna and utility pole grounding wire inductively coupled to my PL-606 as in the video clips below.
http://www.youtube.com/watch?v=gyhuL8sdNeU
http://www.youtube.com/watch?v=0wCT-DxAfJY
http://www.youtube.com/watch?v=yyH8roZYys8
http://www.youtube.com/watch?v=gRB-64G4iws
http://www.youtube.com/watch?v=5ay5k3txG_Q - this was recorded at my house, the above 4 were recorded in rural Pauma Valley in north San Diego county

Also, as for being up to a weather challenge ... we don't get as much rain here, but we do frequently have to deal with hundred-plus-degree temperatures in summer.  I've even had my PL-606 temperature display peg outside at 121° and my PL-398mp peg at 122°, and will often even see the display turn dark from the heat.  How would you deal with that? :)

After you return and when you have some time, is there a chance you could post a mediumwave bandscan on one (or more) of your barefoot (no external 7.5" loopstick modification) Tecsun ultralights?  I did one - http://www.youtube.com/watch?v=ylEOx3TRNVg - with my PL-398mp, which I realize is not a ULR.  I also tried one on my PL-606 - http://www.youtube.com/watch?v=KKf4IqAy1Sk - but between having the frequency display not functioning (forcing me to rely on station presets from 540 to 1530 kHz, and another radio's 450 kHz local oscillator above that) and the display being very dark due to the intense heat outside that day, it's very tough to read the display, I think.
I personally would like to videos of other bandscans in addition to mine, like yours, others, etc, so I could get an idea of what the local stations / QRM are like in other locations. :)


73 and good DX,
Stephen Airy



________________________________
 From: "d1028gary@xxxxxxx" <d1028gary@xxxxxxx>
To: ultralightdx@xxxxxxxxxxxxxxx; irca@xxxxxxxxxxxxxxxx 
Sent: Friday, July 20, 2012 1:29 PM
Subject: [IRCA] Oregon Cliff Ultralight DU's for 7-20
 
Hello All,

The typical rules of medium wave propagation seemed to be thrown out the window this morning on the Cliff, as numerous low-powered New Zealand stations tested the overload level of the Tecsun PL-380 Ultralight. 2.5 kW Radio Kahungunu (a Maori-language station which has apparently never been heard at Grayland) was maxing out the PL-380's S/N display at 25 for about 5 minutes with its distinctive Island Music around 1230, while 828-Radio Trackside (2 kW) was solid copy at the same time. 567-RN, 657-Southern Star, 675-RN and 603-Waatea all were maxing out the PL-380's S/N at 25 this morning, and although the time was limited, I crammed in as much fanatical DXing as I could.

The Aussies were decidedly weaker than the Kiwis this morning, but I pushed my luck by checking for X-band Aussies (all 400 watts or less). On the X-band the Aussies had no New Zealand competition, and on 1701 kHz I was lucky to find fairly decent DU English audio as soon as I tuned in. For some unknown reason the Tijuana ESPN noise generator was silent, and I was able to record a fairly decent ID from an obscure Christian broadcaster on the frequency. Totally wacky!

The rain and wind were nasty on the Cliff this morning, but fortunately the hot-rodded radios and FSL antennas were up to the weather challenge. Thanks very much to Nick, Steve and Dennis for the daily DU-DXing reports... but I feel more than a little embarassed at the relative results here. I wish that you could all join me for at least one of these wacky ULR + FSL transoceanic sessions (like Norm Clark plans to do tomorrow morning)... the experience would probably turn any of you into a DU-DXing fanatic!!

73, Gary DeBock (temporarily DXing at Cape Perpetua, OR ocean side Cliff, 400' high)
7.5" Medium Wave Loopstick PL-380 (new design) + 8" MW FSL antenna



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