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Old 3-Jun-2017, 12:58 AM   #1
Sev
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Join Date: Jan 2016
Posts: 81
Arrow DB8e VHF-Lo & High

Just an FYI in case it has not come up

Just picked up a used DB8e that the other day while in Florida.
This evening I was scanning my locals with it using an Avermedia stick.
I was using an RCA preamp with it.

It picked up my 2 VHF high and Lo channels.

https://transition.fcc.gov/fcc-bin/tvq?call=WCYB
https://transition.fcc.gov/fcc-bin/tvq?call=WEMT

This is a pleasant surprise. And quite unexpected.
This will save me the trouble of having to mount my Archer Vhf or buying a that Winegard HD8200U I have been looking at.

I hope this information proves to be useful.

Cheers.
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Old 18-Jun-2017, 12:06 PM   #2
mikecandu
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Hi,

I'm surprised you got any VHF channels. I'm in Hamilton Ontario and didn't get any even though CTV here (CH9 Toronto) is pretty strong. I bought the optional rabbit ears and now get two VHF channels, Channel 9 and 13 (CTV Kitchener)

Mike
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Old 18-Jun-2017, 5:46 PM   #3
ADTech
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Since he's less than 10 miles from his VHF stations, it's not surprising at all.

While we might occasionally suggest trying a UHF antenna in strong VHF signal locations to see if it might pick up local VHF signals, it's not something that is predictable and is not something that we will specifically recommend with any expectations. The results will be potluck.

Any antenna, when used for out-of-design-band reception attempts, will usually be very near-sighted and the reception patterns or directions will usually be at odd angles to designed performance. One example of this can be seen if one looks at the UHF patterns of our ClearStream 5 in its data sheet. For example, on UHF 35 or so, the thing is somewhat nearsighted straight ahead but has lobes on both sides of boresite.

As another example, the DB4e has a fair amount of reception about 30 degrees left of boresite on the upper VHF channels but doesn't have a corresponding reception lobe to the right of boresite.

Complicating the assessment is the UHF balun used on our outdoor UHF antennas which allows the coax shield to be used as a reception element for VHF via feedline radiation. Since the routing of the coax by any given customer is going to vary from one customer to the next, expecting this mode of reception to work usually isn't realistic. Due to this, it is our firm recommendation to customers that, if you NEED VHF reception, you should PLAN for it instead of relying on chance or unpredictable methods.
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Last edited by ADTech; 18-Jun-2017 at 5:52 PM.
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Old 19-Jun-2017, 5:38 PM   #4
rabbit73
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Quote:
Originally Posted by ADTech View Post
it is our firm recommendation to customers that, if you NEED VHF reception, you should PLAN for it instead of relying on chance or unpredictable methods.
Good summary; I agree.

Thanks for the background on the patterns of your antennas when used for reception on another band.

Sev's report for reference:
http://www.tvfool.com/?option=com_wr...e6a4eb00f15cb9
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Last edited by rabbit73; 19-Jun-2017 at 10:12 PM.
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Old 2-Feb-2018, 6:26 PM   #5
Sev
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Join Date: Jan 2016
Posts: 81
Quote:
Originally Posted by ADTech View Post
Since he's less than 10 miles from his VHF stations, it's not surprising at all.

While we might occasionally suggest trying a UHF antenna in strong VHF signal locations to see if it might pick up local VHF signals, it's not something that is predictable and is not something that we will specifically recommend with any expectations. The results will be potluck.

Any antenna, when used for out-of-design-band reception attempts, will usually be very near-sighted and the reception patterns or directions will usually be at odd angles to designed performance. One example of this can be seen if one looks at the UHF patterns of our ClearStream 5 in its data sheet. For example, on UHF 35 or so, the thing is somewhat nearsighted straight ahead but has lobes on both sides of boresite.

As another example, the DB4e has a fair amount of reception about 30 degrees left of boresite on the upper VHF channels but doesn't have a corresponding reception lobe to the right of boresite.

Complicating the assessment is the UHF balun used on our outdoor UHF antennas which allows the coax shield to be used as a reception element for VHF via feedline radiation. Since the routing of the coax by any given customer is going to vary from one customer to the next, expecting this mode of reception to work usually isn't realistic. Due to this, it is our firm recommendation to customers that, if you NEED VHF reception, you should PLAN for it instead of relying on chance or unpredictable methods.
Sorry I missed your reply.

Thank you for the input.

On a side note.

I will be modding the DB8e.
Adding 2 NOS channel master baluns and a Holland GHS-2Pro
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