ATSC 3.0 Washington, DC

ATSC 3.0 Forum
green97
Posts: 18
Joined: Thu Sep 15, 2022 5:06 am
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Re: ATSC 3.0 Washington, DC

Post by green97 »

Glad you got it figured out.

> The RF33 ATSC 3.0 stations in DC are located in Merrifield

DC has three ATSC 3.0 transmitters:

RF33 WHUT hosts WRC, WTTG, WJLA, WUSA, WHUT. It's in NW DC on the same tower as 1.0 WETA, WJLA, WUSA.

RF30 WIAV hosts TBD, WJLA 24/7 News. NW DC on same tower as 1.0 WRC and multiple class A and low power 1.0 stations.

RF6 WDCN-LD hosts Country Music Network and Franken FM 87.75 La Nueva. In Merrifield, VA.

In Baltimore:

RF25 WNUV hosts WMAR, WBAL-encrypted, WBFF, WNUV, WMPT. On TV Hill in NW-ish Baltimore City with their 1.0 counterparts (less WMPT) and WJZ.

Visit rabbitears.info for more details.

decaym
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Location: McLean, VA
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Re: ATSC 3.0 Washington, DC

Post by decaym »

foxbat121 wrote: Wed May 31, 2023 5:58 am The RF33 ATSC 3.0 stations in DC are located in Merrifield, not DC, from the information I gathered. They are the easiest to receive for me even though I'm 20+ miles out in the west. All I need is the cheap indoor square antenna with or without amp as long as I use the side of my house that facing that direction. Flex 4k has no issues even if I just lay the antenna flat on the top of the table.
I'm not sure you are correct on that. Using the Antenna's Direct locator, I show the NextGen channels in the same location as several of the other towers in DC. The only thing I see showing at the Merrifield location is a VHF station. I always wondered what that big antenna was down there!

Code: Select all

WDCN-LD FAIRFAX, VA
Band: VHF
Lat: 38.8745
Lng: -77.223222222222
If that was the ATSC 3 station, I don't think I would pick it up at all as it is off the back side of my directional antenna. Certainly wouldn't show 100% signal strength.

Code: Select all

Virtual Channel	104.1 WRC
Frequency	587.000 MHz
Program Number	4
Modulation Lock	atsc3
Signal Strength	100%
Signal Quality	100%
Symbol Quality	100%
Edit: OK, green97 answered it much better. Just didn't see it as it was on page 2 when I was replying to page 1. Oh, and I didn't even know it was possible to send ATSC over VHF-Lo (RF channel 6).

kyl416
Posts: 474
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Device ID: 1080DB11,1040501B
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Re: ATSC 3.0 Washington, DC

Post by kyl416 »

decaym wrote: Wed May 31, 2023 12:22 pmOh, and I didn't even know it was possible to send ATSC over VHF-Lo (RF channel 6).
That's the only way Franken FM stations can still exist after the analog cutoff for LPTV. ATSC 3.0 lets them limit the required digital signal to 82-87.5 MHz, and have a STA for an analog FM signal on 87.75

Also, Antenna Direct's predictions are pretty much useless as it operates only by radius and doesn't even take the stations power, height and signal pattern into account, and gives data that is flat out wrong whenever it "predicts" reception of a translator instead of the main signal. Like it claims my strongest station is a 0.024 kW Class A VHF 9 station from 24 miles away even though I'm not even in its contour as it has a null towards my direction and is terrain blocked to protect the full power 80.6 kW VHF 9 station from 41 miles away that I actually get strong reception of. It also claims I'll get stronger reception of a 10.2 kW UHF translator on the same tower as that full power VHF 9 station (and incorrectly lists the UHF 31 number of its main signal from 70+ miles away instead of the UHF 25 number of the translator). For my local Fox affiliate, it lists the tower of its translator, which I also have no chance of getting, instead of its main signal I actually get strong reception of. You're better off using the RabbitEars search.

foxbat121
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Device ID: 10A57CFF
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Re: ATSC 3.0 Washington, DC

Post by foxbat121 »

decaym wrote: Wed May 31, 2023 12:22 pm
foxbat121 wrote: Wed May 31, 2023 5:58 am The RF33 ATSC 3.0 stations in DC are located in Merrifield, not DC, from the information I gathered. They are the easiest to receive for me even though I'm 20+ miles out in the west. All I need is the cheap indoor square antenna with or without amp as long as I use the side of my house that facing that direction. Flex 4k has no issues even if I just lay the antenna flat on the top of the table.
I'm not sure you are correct on that. Using the Antenna's Direct locator, I show the NextGen channels in the same location as several of the other towers in DC. The only thing I see showing at the Merrifield location is a VHF station. I always wondered what that big antenna was down there!
That was what I got on Atennaweb.com. So, may not be accurate but other sites are not clear on that either. Who knows.

jhsmith
Posts: 11
Joined: Tue May 30, 2023 8:50 am

Re: ATSC 3.0 Washington, DC

Post by jhsmith »

To more thoroughly explore the difference between the flex and the duo, I added a 6 db attenuator to the flex. Significant reduction in channels. Added a 2nd amplifier (another 15 dB). Bingo, that was it. 38 channels of ATSC 1.0 and 7 ATSC 3.0 channels. Still not matching the 68 ATSC 1.0 channels of the duo but significantly better than my starting point. My conclusion is the AGC loop in the flex is not as robust as the one in the duo.

Has SD ever released the details of both designs? Which chipsets? Block diagram of any external AGC loops and filters?

nickk
Silicondust
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Re: ATSC 3.0 Washington, DC

Post by nickk »

That doesn't sound right. Both are connected to the same splitter correct?

Can you please enable "send diagnostic information" on each, run a channel scan on each, then post both Device IDs.

Nick

jhsmith
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Joined: Tue May 30, 2023 8:50 am

Re: ATSC 3.0 Washington, DC

Post by jhsmith »

Nickk,

Sorry, just saw this. I'll gather that data and get back to you. Thanks for caring.

Both were connected to the same splitter (before I added the amp). Now the duo is on the splitter and the flex 4k is on the splitter but has an additional 15dB line amp.

About 9 miles west of the DC transmitters. Upper VHF / UHF Yagi in the attic (30 feet above ground), wood siding, SD LTE filter then Channel Master antenna amp then Philips LTE filter then 4 way splitter then SD duo. Add 15 dB line amp for flex 4k. I've tried a bunch of configurations. duo is pretty robust with regard to signal level, flex 4k required extra amp to get more than a few channels.

2nd LTE filter didn't do much but increased channel count slightly.

Jim

jhsmith
Posts: 11
Joined: Tue May 30, 2023 8:50 am

Re: ATSC 3.0 Washington, DC

Post by jhsmith »

Nickk,

Diagnostics on. Ran channel scan on both.

DUO - 106AC0B7 (LTE filters plus antenna amp)
4k - 1081333E (LTE filters plus antenna amp plus additional 15dB distribution amp)

After you get this data, let me know and I can run the 4k without the extra amp.

Jim

jasonl
Silicondust
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Re: ATSC 3.0 Washington, DC

Post by jasonl »

Received scan logs from 106AC0B7 but not from 1081333E. Please disable/re-enable the setting on the device's web page and run another scan.

jhsmith
Posts: 11
Joined: Tue May 30, 2023 8:50 am

Re: ATSC 3.0 Washington, DC

Post by jhsmith »

Toggled setting and rescanned channels

jhsmith
Posts: 11
Joined: Tue May 30, 2023 8:50 am

Re: ATSC 3.0 Washington, DC

Post by jhsmith »

Jason,

Did you get that log?

Jim

jasonl
Silicondust
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Re: ATSC 3.0 Washington, DC

Post by jasonl »

Yes, there's a hardware fault with 1081333E. It looks like it's out of warranty, but we can offer a discount on a replacement if you're interested, just open a trouble ticket and include a link to this thread.

https://www.silicondust.com/support/trouble-ticket/

jhsmith
Posts: 11
Joined: Tue May 30, 2023 8:50 am

Re: ATSC 3.0 Washington, DC

Post by jhsmith »

Thanks to NickD and JasonL at SD, I received a replacement for the Flex4k. For simplicity, I'm using the metric of number of channels "received" during a channel scan. This does not necessarily mean that all of them have good reception although spot checking shows that almost all of them do have good reception.

Refurb Flex 4k with firmware as shipped 58 ATSC 1.0 channels + 12 ATSC 3.0
Refurb Flex 4k with latest firmware 53 ATSC 1.0 + 12 ATSC 3.0 + 15 music
Existing Duo 54 ATSC 1.0
Similar reception to the ATSC 3.0 tuner in LG TV but I didn't count the exact channels.

So they are all roughly equivalent now and what I would call working well. About 9 miles from DC towers near American University, attic yagi about 30 ft AGL, 305 ft MSL, SD LTE filter + CM antenna amp + Philips LTE filter + 4 way splitter.

Happy with the support and performance from SD!

hokietima
Posts: 26
Joined: Sun Sep 11, 2011 5:25 am

Re: ATSC 3.0 Washington, DC

Post by hokietima »

Just got my reception fixed by installing a new Televes DATBOSS LR Mix and I'm now getting all my channels reliably. Can someone explain the audio channels in the DC area? They are 10001 to 10015 in the HDHR Flex 4K lineup and are on RF Ch 25. RF Ch 25 doesn't show up in my Rabbit Ears report. Just curious how these audio channels "work".

decaym
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Location: McLean, VA
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Re: ATSC 3.0 Washington, DC

Post by decaym »

hokietima wrote: Sun Jul 23, 2023 4:00 am Just got my reception fixed by installing a new Televes DATBOSS LR Mix and I'm now getting all my channels reliably. Can someone explain the audio channels in the DC area? They are 10001 to 10015 in the HDHR Flex 4K lineup and are on RF Ch 25. RF Ch 25 doesn't show up in my Rabbit Ears report. Just curious how these audio channels "work".
Those audio stations are coming in from the Baltimore lighthouse transmitter. Check the beam direction on your antenna and see if Baltimore is in the general path. You may also see a couple of video channels from there like 102.1 and 111.1, but those have had DRM added so you won't be able to view them. I don't think the audio channels show up on any reports as they are an experimental feature. Surprised me when they appeared on my channel list.

I'm in NoVA about six miles from the DC towers. Baltimore is just outside of my beam but I still pick up some of the stations (barely). Considering adjusting my antenna a bit to point more in that direction as I get more than enough signal from the DC stations (always 100% across the board) with my Antennas Direct ClearStream 4V in the attic. What I have found is that the audio channels are easier to pick up as they use less bandwidth and a more forgiving encoding method.

Just to compare, I'm picking up 106 channels in total when I do a scan. Most of those are DC but also some Baltimore. The ATSC 3 channel list is much shorter, so here it is:

Code: Select all

102.1	WMAR	
104.1	WRC	
105.1	WTTG	
106.1	WDCN	
107.1	WJLA	
109.1	WUSA	
111.1	WBAL	
122.1	WMPT	
132.1	WHUT	
145.1	WBFF	
154.1	WNUV	
158.1	WIAV	
158.5	24/7MMT	
10001	Hit List	
10002	Classic Rock	
10003	Greatest Holida	
10004	Alternative	
10005	Pop Adult	
10006	Hip Hop	
10007	Hot Country	
10008	Flashback 70s	
10009	Everything 80s	
10010	Latin Pop	
10011	Karaoke	
10012	Naturescape	
10013	Qello Concerts	
10014	Classica	
10015	Djazz

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