Forum: Antennas
12-Jun-2020, 10:06 PM
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Replies: 33
Views: 294,405
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Forum: Antennas
12-Jun-2020, 8:29 PM
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Replies: 33
Views: 294,405
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Forum: Antennas
12-Jun-2020, 4:55 PM
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Replies: 33
Views: 294,405
CM-0264 Preamp
Seems feasible.
Main item is additional balun.
PCB traces are already there. Need to cut an etch connecting UHF & VHF, etc. Probably have to solder in a small jumper.
Maybe touch up...
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Forum: Antennas
12-Jun-2020, 2:40 PM
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Replies: 33
Views: 294,405
Good morning Sev.
The CM 0064DSB has...
Good morning Sev.
The CM 0064DSB has a regular ferrite 300:75 Ohm balun at its input.
The core and windings are seen in the lower right of this image (near input terminals).
...
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Forum: Antennas
12-Jun-2020, 10:58 AM
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Replies: 33
Views: 294,405
Ferrite, Wavelength, etc.
Not clear how your choke balun is configured?
The choke balun does not make impedance transformation as regular 300:75 Ohm baluns would.
For example; two 300-Ohm antennas paralleled would...
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Forum: Antennas
11-Jun-2020, 2:00 PM
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Replies: 33
Views: 294,405
Thanks for the RE report.
Looks like you...
Thanks for the RE report.
Looks like you have several strong signal stations to choose from.
As you know, there are several other factors that affect received signal strength besides...
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Forum: Antennas
10-Jun-2020, 3:19 PM
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Replies: 33
Views: 294,405
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Forum: Antennas
3-Jun-2020, 1:37 PM
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Replies: 13
Views: 83,674
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Forum: Antennas
1-Jun-2020, 7:48 PM
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Replies: 33
Views: 294,405
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Forum: Antennas
26-May-2020, 9:11 PM
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Replies: 13
Views: 83,674
Yes it might.
Have examined a few of those. ...
Yes it might.
Have examined a few of those. Those examined here are not good quality.
The connection inside was pressure contact, probably very light pressure contact.
The parts that grab...
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Forum: Antennas
26-May-2020, 6:09 AM
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Replies: 13
Views: 83,674
They?
See one image. It is open combiner...
They?
See one image. It is open combiner case.
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There could be other difficulties, but a noticable one is:
A difficulty with combining UHF with...
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Forum: Antennas
29-Apr-2020, 8:57 AM
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Replies: 2
Views: 57,095
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Forum: Antennas
21-Apr-2020, 4:00 PM
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Replies: 1
Views: 23,246
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Forum: Antennas
18-Apr-2020, 1:52 PM
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Replies: 39
Views: 97,919
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Forum: Antennas
17-Apr-2020, 6:50 PM
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Replies: 4
Views: 69,359
Conical Yagis
Yes.
It is a stacked pair of conical Yagis. Very popular TV antenna in the 1950-1970 time range.
The Conical Yagi covers both high and low VHF channels with moderate gain.
The conical...
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Forum: Antennas
13-Apr-2020, 3:13 PM
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Replies: 2
Views: 18,482
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Forum: Antennas
11-Apr-2020, 5:27 PM
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Replies: 39
Views: 97,919
Thanks for the image.
The location of the...
Thanks for the image.
The location of the single antenna may be a better location with respect
to multipath (likely ground reflections).
Best current guess; the problem is external and...
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Forum: Antennas
11-Apr-2020, 1:35 PM
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Replies: 39
Views: 97,919
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Forum: Antennas
10-Apr-2020, 5:49 PM
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Replies: 39
Views: 97,919
The blue trace (antenna pair) shows a dip in...
The blue trace (antenna pair) shows a dip in middle of RF 8 spectrum.
That is indicative of two signals interfering with each other (out-of-phase).
An out-of-phase condition can result from:
...
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Forum: Antennas
7-Apr-2020, 7:21 PM
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Replies: 39
Views: 97,919
Interesting project, Bob.
Yes true. ...
Interesting project, Bob.
Yes true.
Many models that I have seen, especially at UHF, fail to account for everything that can affect results.
Partially because NEC2 makes it difficult...
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Forum: Special Topics
27-Mar-2020, 9:28 PM
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Replies: 15
Views: 111,831
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Forum: Antennas
4-Aug-2019, 6:49 PM
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Replies: 5
Views: 28,110
JFD & Area Special Antenna
Yes, second that. Thanks bobs. Interesting antennas.
The top antenna in the 1st image above is a JFD UHF/VHF combo.
http://forum.tvfool.com/attachment.php?attachmentid=3469&d=1564943779
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Forum: Antennas
9-Apr-2019, 6:03 PM
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Replies: 3
Views: 21,388
JFD Zig-A Log
Top antenna, probably:
JFD Zig-A-Log (image below)
http://forum.tvfool.com/attachment.php?attachmentid=3354&d=1554832918
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Forum: Antennas
5-Apr-2019, 3:06 PM
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Replies: 10
Views: 27,533
Thanks, good to be able to appreciate...
Thanks, good to be able to appreciate accomplishments of the past.
Yes, agreed.
Rabbit73 & bobsgarage, it is interesting.
The antenna engineers of the early 50s thru about mid 70s did...
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Forum: Antennas
3-Apr-2019, 6:33 PM
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Replies: 10
Views: 27,533
Channel Master TW: Traveling Wave Antennas
The antenna is a Channel Master 'TW' antenna. TW for traveling wave.
It was a revolutionary antenna in its day.
Previously, relatively high-gain antennas were narrowband (Yagis).
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