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mp11
02-09-2010, 02:00 PM
Anyone have any experience with this (http://www.antennacraft.net/pdfs/HDMS9100.pdf) type antenna for ES? I currently use it for tropo and it seems to perform pretty well, any reason why it wouildn't perform with Es? Thanks.

Boško Igić
02-10-2010, 09:29 AM
Anyone have any experience with this (http://www.antennacraft.net/pdfs/HDMS9100.pdf) type antenna for ES? I currently use it for tropo and it seems to perform pretty well, any reason why it wouildn't perform with Es? Thanks.

Why you don't buy the 3-element (or more) Low VHF antenna, 10-element (or more) High VHF antenna and UHF antenna with minimum 10 X-es? Your Omni will perform poor on low VHF because your Omni have -16 dB gain on low VHF (as opposed to typical Low VHF Yagi's around 4-6 dB, around 20 dB difference, Yagi is winner),-6 dB in VHF High(Typical High Bnd Yagi gain is arr. 10 dB, 16 dB difference) 2,5 dB in UHF (difference between typical hi-gain ant is 10-13 dB). Adding amplifier to lo-gain ant. can made very little difference. Your ant. is poor for Es.

mp11
02-10-2010, 10:48 AM
[QUOTE]Why you don't buy the 3-element (or more) Low VHF antenna, 10-element (or more) High VHF antenna and UHF antenna with minimum 10 X-es? Your Omni will perform poor on low VHF because your Omni have -16 dB gain on low VHF (as opposed to typical Low VHF Yagi's around 4-6 dB, around 20 dB difference, Yagi is winner),-6 dB in VHF High(Typical High Bnd Yagi gain is arr. 10 dB, 16 dB difference) 2,5 dB in UHF (difference between typical hi-gain ant is 10-13 dB). Adding amplifier to lo-gain ant. can made very little difference. Your ant. is poor for Es.

Well, I wont pretent to understand all the numbers you ran by me, but I appreciate your candid response. :)

1- just to clarify, you call my antenna an "Omni" when in fact it's directional.
2-
Your Omni will perform poor on low VHF because your Omni have -16 dB gain on low VHF (as opposed to typical Low VHF Yagi's around 4-6 dB, around 20 dB difference, Yagi is winner),-6 dB in VHF High(Typical High Bnd Yagi gain is arr. 10 dB, 16 dB difference) 2,5 dB in UHF (difference between typical hi-gain ant is 10-13 dB
Very helpfull info. Now I understand what specs to look for in an "Es fetching" antenna. So now that begs the question...looking at the specs on my round directional for Es, how does it stack up as far as tropo? I've pulled in quite a few 400+ mile catches and a couple of 500+ mile catches so far.

Note: What do you think about THIS (http://www.solidsignal.com/pview.asp?mc=03&p=Y5-2-6&d=AntennaCraft-Y526-LowbandBroadband-VHF-Yagi-TV-Antenna-Channels-26-(Y526)&sku=716079000949) one for Es?

Boško Igić
02-10-2010, 01:12 PM
Note: What do you think about THIS (http://www.solidsignal.com/pview.asp?mc=03&p=Y5-2-6&d=AntennaCraft-Y526-LowbandBroadband-VHF-Yagi-TV-Antenna-Channels-26-(Y526)&sku=716079000949) one for Es?

This is good one for VHF Low. You will get more channels on VHF Low on this antenna than on your very poor UHF antenna.

K4NBF
02-10-2010, 01:53 PM
Now I understand what specs to look for in an "Es fetching" antenna. So now that begs the question...looking at the specs on my round directional for Es, how does it stack up as far as tropo? I've pulled in quite a few 400+ mile catches and a couple of 500+ mile catches so far.


Mike,

There are no qualities that make an antenna better suited for any particular mode of propagation (Es, tropo, etc.) than another.

The issue at hand is that E-Skip generally does not reach RF Channel 7 and above. Thus, for Es, you want an antenna that performs well on Channels 2-6, as that is where you will get virtually all of your Es catches.

Tropo is possible on all frequencies/channels, although Channel 7 and above are more prone than low VHF channels. Thus, for tropo, you want an antenna with as much gain (and other stats like front-back rejection, etc) as possible on high channels.

As Bosko pointed out, the antenna you are using now is geared toward UHF, and performs poorly on VHF based on those gain numbers. Since you obviously want to DX both Es and Tropo, you can either get separate antennas for VHF and UHF, and have high performance on both bands, or settle for a VHF/UHF combo, which takes less space and capacity, but will not perform as well.

I will refrain from recommending any antennas as I generally don't DX TV.

mp11
02-10-2010, 09:49 PM
OK based on what you guys have said, let me sum up what I've understood about my antenna.
1- Due to a very poor VHF low gain (Es catches probably unlikely)
2- A VHF high gain that is not much better
3- And UHF gain that is adequate for tropo
This may explain why out of my current 85 catches, only about 14 are VHF, and of that only 1 is VHF low (KCWX).

So I think what I'll do for the time being, is keep the current antenna for now and get this one (http://www.solidsignal.com/pview.asp?mc=03&p=Y5-2-6&d=AntennaCraft-Y526-LowbandBroadband-VHF-Yagi-TV-Antenna-Channels-26-(Y526)&sku=716079000949)as a separate antenna for the upcoming Es season. Unless someone has another recommendation.

Thanks to you guys for enlightening my on the meaning behind those gain numbers. :)

w9wi
02-11-2010, 10:01 AM
OK based on what you guys have said, let me sum up what I've understood about my antenna.
1- Due to a very poor VHF low gain (Es catches probably unlikely)
2- A VHF high gain that is not much better
3- And UHF gain that is adequate for tropo
This may explain why out of my current 85 catches, only about 14 are VHF, and of that only 1 is VHF low (KCWX).

So I think what I'll do for the time being, is keep the current antenna for now and get this one (http://www.solidsignal.com/pview.asp?mc=03&p=Y5-2-6&d=AntennaCraft-Y526-LowbandBroadband-VHF-Yagi-TV-Antenna-Channels-26-(Y526)&sku=716079000949)as a separate antenna for the upcoming Es season. Unless someone has another recommendation.

Thanks to you guys for enlightening my on the meaning behind those gain numbers. :)

I forget how long you've been DXing -- do I remember properly that you started *after* the full-power analog stations went off? (i.e., all your DXing has been digital?)

Point being that your low-band situation may not be as bad as you think. There are VERY few low-band digital stations. (a high-profile Chicago station had MASSIVE problems with digital operation on RF channel 3*, that publicity scared most stations into electing high-band VHF or UHF.) I would regard KCWX digital as a VERY good catch from your location -- either it's really short Es or really long tropo.

Have you been checking for analog signals on low-band? They do remain on the air in other countries.

Es signals (unlike tropo) tend to be pretty strong. A better antenna always helps, but it isn't (IMHO) as important for Es as it is for tropo.

* I do think many -- but by no means all -- of those problems were due not to the low-band channel but to an unreasonably low power assignment.

mp11
02-11-2010, 03:43 PM
[QUOTE]I forget how long you've been DXing -- do I remember properly that you started *after* the full-power analog stations went off? (i.e., all your DXing has been digital?)

Yeah Doug I started about in August. All my DXing has been digital, with a couple of analog exceptions, XERV-9 Reynosa and XHOR-14 in Matamoros.


I would regard KCWX digital as a VERY good catch from your location -- either it's really short Es or really long tropo.

KCWX is 369 miles from my home. I assumed from that distance is was tropo. But for future reference, how can I tell if a catch in that "in-between distance," is Es or tropo?


Have you been checking for analog signals on low-band? They do remain on the air in other countries.

Well, when I see indications of Es, I place my Insignia on manuel scan channel 2. But nothing has ever come even close to showing up.


* I do think many -- but by no means all -- of those problems were due not to the low-band channel but to an unreasonably low power assignment.

Hmm. OK I'm not sure I understand what you mean.

Danny
02-11-2010, 09:14 PM
Mike, your reception of KCWX was via tropo. This quote from one of your reports in January indicates that you received KCWX while other stations were in via tropo:

"Friday night tropo gave me my first Mexico catches, and my first ever low band catch KCWX-DT 2.1 RF 5."

Es is rare after 9PM and before 8AM. It is not common to have tropo and Es at the same time, either.

Those are the basics. There is a lot more, which you find on other Web sites.

mp11
02-11-2010, 09:26 PM
[QUOTE]Mike, your reception of KCWX was via tropo. This quote from one of your reports in January indicates that you received KCWX while other stations were in via tropo:

"Friday night tropo gave me my first Mexico catches, and my first ever low band catch KCWX-DT 2.1 RF 5."

Yep thats kinda how I saw it at the time. ;)


It is not common to have tropo and Es at the same time, either.

That, I didnt know. Thanks Danny.

P.S. Danny you guys getting snow up there?

Danny
02-11-2010, 09:50 PM
We've got snow.

w9wi
02-11-2010, 11:44 PM
[QUOTE=w9wi;11385]

Yeah Doug I started about in August. All my DXing has been digital, with a couple of analog exceptions, XERV-9 Reynosa and XHOR-14 in Matamoros.



KCWX is 369 miles from my home. I assumed from that distance is was tropo. But for future reference, how can I tell if a catch in that "in-between distance," is Es or tropo?



Well, when I see indications of Es, I place my Insignia on manuel scan channel 2. But nothing has ever come even close to showing up.



Hmm. OK I'm not sure I understand what you mean.

Good advice from Danny all around. (yikes, it's snowing up there?)

I would suggest if you've logged a 369-mile-distant low-band VHF digital via tropo, there's probably nothing wrong with your low-band system.

(though an improved low-band system is likely to also be useful for FM DX, which could be a LOT of fun down there!)

My reference to the "unusually low power assignment" in Chicago is that the station in question (WBBM) was initially authorized for only 1 kilowatt of power. They got it modified, eventually up to 4.4kw, but that's still only 1/10 of the maximum permissible power for low-band.

The station just wasn't powerful enough to punch through typical suburban noise.

Today they're running 8 kilowatts on channel 12 & it's working a lot better. (though that's still not nearly enough power...)

NN2E
05-11-2010, 12:22 PM
My two cents worth on the power issue.

KFVS 12 Cape Girardeau, MO. 70 miles from here...

When KFVS was an analog station they ran 316 KW ERP. You could watch them on a portable TV, with only a whip antenna, no problem. I used to rely on them during severe WX events.

Now that they've switched to DTV they're running only 6.8 KW ERP. You can forget about watching them on any kind of whip or "rabbit ears" antenna. Even with a Rad-Shack VU-110 antenna, on the second floor of the house, pointed at KFVS, reception was marginal at times. I've since added a pre-amp to the indoor antenna and now KFVS is nearly 100% reliable. But...

...If there's thunderstorm activity, in the area, their signal becomes unusable. Even when using the DX antenna system (which is always unhooked during severe WX) KFVS still suffers from lightning induced signal break-up.

The bottom line is... Thanks, in part, to their relatively puny output power, I can no longer rely on KFVS during severe WX events.

73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

w9wi
05-11-2010, 10:05 PM
...and UHF antenna with minimum 10 X-es?

My post here is kinda off-topic, but UHF antennas with X-shaped reflectors are generally not available in North America. I have no idea why!

Boško Igić
05-12-2010, 04:30 PM
My post here is kinda off-topic, but UHF antennas with X-shaped reflectors are generally not available in North America. I have no idea why!
directors

Michael Evans
07-21-2010, 01:53 PM
hi. If you were to pen up the case I wonder what you would find inside not a lot I bet, a lot of these wonder antennas are no more than some tin foil stuck to the inside with a wide band amp if your lucky, open it up before parting with your cash, better off with a propper antenna. Mike MBR UK.