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One question: is there an "affordable" coax antenna signal meter anyone could recommend? In case I need to up to a directional antenna it would definitely make placement easier than "trial and error" off my Tablo tuner.
I've seen this kind of location in the Bay Area before and even though the report shows adequate signals, multipath overwhelms the direct path signals and makes reception impossible. Go ahead with your 4V plan and see what happens. If you receive little or nothing then it's hopeless. If you're missing just a couple of stations then an antenna upgrade might do the trick.

A signal meter may not be helpful because it can't distinguish direct path signals from multipath signals.

Chuck
 

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I decided to check the input SWR of the Televes preamp. I measured Return Loss using an HP86207A 75 ohm directional coupler and my spectrum analyzer. I used my coax baluns. The yellow trace on each display is the return loss using a 300 ohm or 75 ohm (where applicable) carbon resistor as a dummy load to verify the setup was working. The magenta trace is the preamp. The test was run with power applied to the preamp and the input terminated.

The results are not very good on UHF and bad on VHF. At this point I can only see two possibilities; 1) the preamp just isn't very good or 2) the preamp is defective. If they wanted, Televes could send me a replacement and I'd test it, publishing the results, good or bad.

Chuck

UHF Input SWR 300 Ohms

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VHF Input SWR 300 Ohms

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VHF Input SWR 75 Ohms

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FYI...KMMC virtual channel 40 has moved to virtual channel 30, still on RF 14. There was a conflict, now that they're transmitting from Sutro Tower, with KTXL, virtual 40, out of Sacramento (Walnut Grove). 30.2 is KMTP, which is also virtual 32, RF 28, from Mt. San Bruno.
 

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The setup shown in the pictures is inadequate. The cables should be routed adequately and the measurements made with the amplifier closed. The jumpers are too long, which in addition to the lack of shielding in this experiment is probably altering the measurements and likely why it's proving challenging to get a proper VHF reading. A SWR measurement of almost 0dB is clearly flawed, this is either a short or an open circuit. This can be seen in the measurements, in the KT measurement the spectrum is probably cleaner because having the input conector is making things less challenging in this test bed.

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In a previous post 0.2dB are added to the KT calculation (some kind of losses due to the setup, probably), while 0.6dB are added to the Televes. There's also the possibility that the amplifier has been damaged after these alterations, or that some of the elements in the chain (adaptor, etc) are not working correctly. The MMIC chipset in this preamplifier is quite resilient and well protected under epoxy, but can become damaged if not handled properly.

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Based on the incorrect SWR values posted it does seem as if the failure is before the MMIC though, likely in the balun or in the input filter. If the same SWR is read in active or passive then the problem is before the MMIC, otherwise it would be the MMIC. The likelihood of the preamp being bad out of the box is almost non-existent since ever single piece is optically and electrically validated at various points in the manufacturing process and undergoes a full functional and specs test before it ever leaves the factory.
 

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Looks like we're down to nitpicking over a few tenths of a dB, a slight difference in lead length and some minor signal pickup from the environment all in an attempt to discredit me while ignoring the elephant in the room. I'm done. The reader can make up his own mind.
 

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I looked at the OTA broadcast MPEG2 streams. You can see the "Northern California" channel logo watermark is actually pretty clear for the bit rate, which indicate the issue reside in the way their OTA equipment resample the original content. When I look at France24's webstream, which I assume is the same as the satellite feed, the quality of those streams are definitely better. When I look at KJPK's own IP stream, the quality is just as bad (also has the watermark). What I see on KJPK is about 240p quality. When I do frame by frame analysis, their OTA equipment seem to introduce some type deinterlace issue...
There is a 30 min daily live broadcast of France 24 at 3pm on 9-3 KQED and 54-3 KQEH. The quality is much better than KJPK.
 
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Same questions here, I never receive any signal from rf 3, and the rf 4 is full of interference

Frank
Hi,

The RF3 and RF4 haven't performed well from Mt. Tamalpais. My rule-of-thumb is that just 5% of people can receive them compared to UHF reception. The plan is to move them to Sutro. I am working on that now. I first wanted to get KQTA-LD built at Sutro, and that happened a month ago. That opens up new revenue streams to then afford being able to build 3 and 4 on Sutro. The channels 3 and 4 should work better on Sutro, because their field strength will be much higher by them being down in the middle of a population area instead of up high on Mt. Tamalpais. I think the 3 and 4 will do especially well with ATSC 3.0.

Blessings,
Keith
 

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Hi,

The RF3 and RF4 haven't performed well from Mt. Tamalpais. My rule-of-thumb is that just 5% of people can receive them compared to UHF reception. The plan is to move them to Sutro. I am working on that now. I first wanted to get KQTA-LD built at Sutro, and that happened a month ago. That opens up new revenue streams to then afford being able to build 3 and 4 on Sutro. The channels 3 and 4 should work better on Sutro, because their field strength will be much higher by them being down in the middle of a population area instead of up high on Mt. Tamalpais. I think the 3 and 4 will do especially well with ATSC 3.0.

Blessings,
Keith
Thanks for your info! Can't wait to get reliable reception from them :)

Frank
 

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Looks like we're down to nitpicking over a few tenths of a dB, a slight difference in lead length and some minor signal pickup from the environment all in an attempt to discredit me while ignoring the elephant in the room. I'm done. The reader can make up his own mind.
Wow, had to catch up as I was out of the area dodging the holiday craze. No worries, that guy is the Televes' US head guy. I got into with him trashing competitor products. He can fluff things to the average consumer but really can't defend against real experts in the field. There is always a gotcha after you peel the layers.
 

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Thanks for your info! Can't wait to get reliable reception from them :)

Frank
Hi,
Is anyone receiving KQRO-LD now (virtual 45, RF 2 from Mt. Chual / Mt. Loma Prieta)? I went to the site New Year's Eve and got it working again after the preamp in front of the receiver had died. When I drove through Morgan Hill, it worked fine using a magnet mount antenna

Blessings,
Keith
 

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Hi,
Is anyone receiving KQRO-LD now (virtual 45, RF 2 from Mt. Chual / Mt. Loma Prieta)? I went to the site New Year's Eve and got it working again after the preamp in front of the receiver had died. When I drove through Morgan Hill, it worked fine using a magnet mount antenna

Blessings,
Keith
I'm receiving KQRO fine again here in SF.

Larry
 

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I'm receiving KQRO fine again here in SF.

Larry
Hi Larry,
Thanks! I’m glad that it is working well again.
I am having a pickle of a time with KKPM-CD being interfered with by KBCW. Today, a viewer at the top of KKPM’s service contour in Orland experienced KBCW block reception from 9AM until 2:30 PM. I am praying that the FCC will help us reach a resolution.
Blessings,
Keith
 

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Today, a viewer at the top of KKPM’s service contour in Orland experienced KBCW block reception from 9AM until 2:30 PM. I am praying that the FCC will help us reach a resolution.
KBCW is 140 miles from Orland so this is a case of tropospheric ducting. What FCC solution could there be for this? The beam heading from Orland to KKPM and KBCW different by 34 degrees. Seems like the viewer needs a highly directional antenna if this is a frequent problem.

Chuck
 

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KBCW is 140 miles from Orland so this is a case of tropospheric ducting. What FCC solution could there be for this? The beam heading from Orland to KKPM and KBCW different by 34 degrees. Seems like the viewer needs a highly directional antenna if this is a frequent problem.

Chuck
Hi Chuck,
Thanks! Interference to the northern lobe of KKPM-CD's coverage is not as common as interference to the southern lobe, which is a common occurrence. The KBCW service contour even overlaps the KKPM-CD service contour. The interference over the southern lob is the main issue that I'm hoping the FCC will help with.
Blessings,
Keith
 

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Hi Chuck,
Thanks! Interference to the northern lobe of KKPM-CD's coverage is not as common as interference to the southern lobe, which is a common occurrence. The KBCW service contour even overlaps the KKPM-CD service contour. The interference over the southern lob is the main issue that I'm hoping the FCC will help with.
Blessings,
Keith
I live just south of Yuba city and I received kbcw about 95 percent of the time before the repack. However, after both stations occupied the same frequency, I no longer receive either station. The fcc should have mandated a lp station in the bay area and a lp station in yuba city to share the same frequency to avoid this problem.
 

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Living in Tri-valley, sure is an RF hell to get signals from Sutro. I have a Winegard HD7698p and CM7778HD v2 setup at 25 ft. The only channel I get from Sutro is a feeble but steady KRON (RF-7) signal. Also, I am able to receive all channels from San Bruno and Mt. Allison.

However, I was happy pointing my antenna towards Walnut Groove and got all of the channels from Sacramento plus the channels from Mt Allison. But after the repack, both KTLN - H&I 68 (RF-22) and KTXL - Fox40 (RF-22) are in the same frequency and I lost both of the channels. So no Fox and no 49ers games this season.

With all the hype about the Televes in this forum and elsewhere in YouTube, I bought the Televes DAT BOSS LR LoV/HiV/UHF Antenna from Lowe's. The quality of the antenna is strong and sturdy. It looks premium. But I was hoping to see if it could get something out of Sutro. Well, nothing great and I lost a few channels. It did not pick up KRON (RF 7) and KNTV (RF 13). This is understandable because this Televes antenna does not have a good VHF reception, as someone pointed in this forum. But the signal strength for KKPX (RF 33) from San Bruno was weaker and at times dropped, compared to my current setup. Instead, the antenna picked up a few channels from Walnut Grove when pointed to Sutro. Now this, I am not able to reason. Then, I tried pointing to Walnut Groove in hopes to see if this antenna could isolate KTXL from KTLN. But as you guessed, no sign of KTXL. Moreover, some of the channels had a very weak performance compared to my current setup. So, I returned the Televes to the store, falling back to my good old Winegard + CM7778.

The only hope I have is ATSC 3.0 and SFNs.

RabbitEars: RabbitEars.Info
 

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Hi,
Is anyone receiving KQRO-LD now (virtual 45, RF 2 from Mt. Chual / Mt. Loma Prieta)? I went to the site New Year's Eve and got it working again after the preamp in front of the receiver had died. When I drove through Morgan Hill, it worked fine using a magnet mount antenna

Blessings,
Keith
Got it. But that station is different here.
Doesn't work at ground level elevation.
So on the roof with a folded dipole & it starts to show up about 20 feet above ground level.

And the only station that requires elevation to work.
Plus the fact the path to here is blocked from that location.
Shows 26-3. Before a scan in.
Not seeing a program guide on that station.
As well as the other new stations.
Only see the program guide on 17-x channels

Whats going on with RF-3 ?
Broken ?.. Not locking ?
 
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