Thanks Dan, I think that explains why I'm having trouble getting reception of CBUT-DT. I hope they fix their problems quickly. I'd like to at least watch the Stanley Cup finals in HD. :(

Thanks Dan, I think that explains why I'm having trouble getting reception of CBUT-DT. I hope they fix their problems quickly. I'd like to at least watch the Stanley Cup finals in HD. :(
We have 7 different ATSC tuners and they are all working on CBUT-DT with no problems. I think it could either be your antenna or local interference.

2.1 signal last night was dropping out like crazy. Problem seem to be affecting 8.1 and 10.1 as well. Only 32.1 was strong and steady.

I got the oppourtunity to play with a spectrum analyzer last night, and I got some interesting readings that others may find useful.:)

In the table below the first column lists the call sign of the station, the second column lists the signal strength, as displayed by the spectrum analyzer for the given frequency, the third column lists the signal strength predicted by TV Fool for my location and antenna height, the fourth column lists the deviation between the TV fool prediction and the real strength measured by the spectrum analyzer, and the last column lists the distance between my antenna and the transmitter.


KVOS-DT | -17 dBm | -033 dBm | +16 dBm | 17.0 mi.
KBCB-DT | -41 dBm | -042 dBm | +01 dBm | 17.1 mi.
CHAN-DT | -49 dBm | -058 dBm | +09 dBm | 44.7 mi.
KCPQ-DT | -52 dBm | -079 dBm | +27 dBm | 86.9 mi.
CHNM-DT | -53 dBm | -056 dBm | +03 dBm | 44.4 mi.
KTBW-DT | -56 dBm | -078 dBm | +22 dBm | 86.8 mi.
KOMO-DT | -60 dBm | -106 dBm | +46 dBm | 80.2 mi.
KCTS-DT | -60 dBm | -109 dBm | +49 dBm | 81.5 mi.
CIVT-DT | -62 dBm | -056 dBm | -06 dBm | 44.7 mi.
KIRO-DT | -62 dBm | -107 dBm | +45 dBm | 80.1 mi.
K24IC-D | -63 dBm | -052 dBm | -11 dBm | 17.1 mi.
KSTW-DT | -64 dBm | -106 dBm | +42 dBm | 81.6 mi.
CKVU-DT | -66 dBm | -058 dBm | -08 dBm | 44.5 mi.
KMYQ-DT | -66 dBm | -103 dBm | +37 dBm | 81.5 mi.
KING-DT | -68 dBm | -107 dBm | +39 dBm | 80.2 mi.
CBUT-DT | -73 dBm | -054 dBm | -19 dBm | 44.4 mi.
KONG-DT | -75 dBm | -106 dBm | +31 dBm | 80.2 mi.

For those who are churious, I am using a Winegard HD7698P antenna and a Channelmaster CM7777 pre-amp. I used the spectrum analyzer to peak the antenna on each channel. The readings I got were the highest ones I could get.

It is heartening to see that TV Fool is pretty conservative in its estimates. For the vast majority of stations the actual signal strength is stronger than TV fool predicted. The only stations that were weaker than their predicted strength were: K24IC-D, CIVT-DT, CKVU-DT, and CBUT-DT.

We know that K24IC-D isn't up to full power yet so that explains why it was reading lower than expected, but I find it very interesting that CIVT, CKVU, and CBUT were reading lower than expected.

I've been having difficulty picking-up CBUT for the last few months, and now I know why -- there isn't any RF for me to lock onto. I now know for a fact that interference isn't the problem because I would have seen it on the spectrum analyzer.

CHNM-DT and CBUT-DT both broadcast from the same tower on Mt. Seymour. CHNM-DT's ERP is supposed to be 8.3 kW, and CBUT-DT's ERP is supposed to be 30.5 kW. Oddly, I am able to receive CHNM-DT's signal at -53 dBM while CBUT-DT's signal is only -73 dBm.

And for the record, I could see RF coming off the antenna from 20 MHz all the way up to 990 MHz. Channel 58, 734 to 740 MHz, is well within the antenna's capability.

If CBUT-DT's ERP was really 22.2 kW stronger than CHNM-DT's ERP I shouldn't be getting 20 dBm more signal strength from CHNM-DT than I get from CBUT-DT. It appears to me that CBUT-DT is broadcasting far far below it's authorized power.

Also, I've seen complaints on this forum about CIVT-DT. I didn't see evidence of adjacent channel interference from channel 32 onto channel 33. CHAN-DT and CIVT-DT broadcast from the same tower. CHAN-DT's ERP is suppoed to be 8.3 kW, and CIVT-DT's ERP is suppoed to be 12.6 kW. Again, I got 13 dBm better signal strength from CHAN-DT than I got from CIVT-DT. That shouldn't be happening if CIVT-DT were really putting out 4.3 kW better ERP than CHAN-DT.

jasonbyers7,

I figured out my CBUT problem. I know for a fact that it's not interference, the RF is just really weak. I got my hands on a spectrum analyzer and found that I had 20 dBm less signal strength from CBUT-DT than CHNM-DT (and both stations broadcast from the same tower).

I blog more about my results here:
http://www.digitalhome.ca/forum/showpost.php?p=1109119&postcount=81

You're in Coquitlam so you're closer to Mt. Seymour than me and so you probably wouldn't notice if CBUT's power was reduced so long as your receivers can still lock on the signal.

Another thing I found interesting was that the spectrum analyzer frequently contradicted the signal strength indicators on my receivers.

Actually, you're not alone Alex. I read your other post earlier today and I have to say your results really correspond with what I experience as well out in Chilliwack. CBUT used to be my strongest station, followed closely by CHAN, both of which I received 100% of the time. I never received CHNM, CIVT or CKVU. However, as of a few weeks ago, CBUT dropped considerably (get it occasionally only) and now, mysteriously, CHNM is my strongest channel and I receive only it and CHAN 100% of the time (of course, I'm talking all digital and am not including my reception of KVOS, KBCB, and KBTC, all of which are blow torches for me).

I was thinking maybe CHNM did something that increased their coverage area, but had a detrimental effect on CBUT's. What do I know though. ..

jasonbyers7,

I figured out my CBUT problem. I know for a fact that it's not interference, the RF is just really weak. I got my hands on a spectrum analyzer and found that I had 20 dBm less signal strength from CBUT-DT than CHNM-DT (and both stations broadcast from the same tower).

I blog more about my results here:
http://www.digitalhome.ca/forum/showpost.php?p=1109119&postcount=81

You're in Coquitlam so you're closer to Mt. Seymour than me and so you probably wouldn't notice if CBUT's power was reduced so long as your receivers can still lock on the signal.

Another thing I found interesting was that the spectrum analyzer frequently contradicted the signal strength indicators on my receivers.

CBUT-DT (ch 58) and CHNM-DT(ch 20) are not from the same tower. CHNM (analog 42) is at CBUT-DT (same antenna). CHNM-DT is at the rogers site.

CBUT-DT transmitter is still operating at the same output power and same reflected power. Our RF level out has not changed.
The only thing I can think of would to do a return loss sweep of your antenna. For whatever reason it could be the antenna is under preforming at that frequency. CBUT-DT (ch 58) is still the strongest RF we pickup in monitoring the digitals from Mt. Seymour.

Thanks Jayson,

If the output power of the CBUT transmitter hasn't changed then I'm stumpped. I guess I'm just going to have to watch in analog on channel 2 for the time being and wait for CBUT-DT to upgrade to channel 43 next year.

I don't think my antenna is under-performing at that frequency. I peaked my antenna on CBUT-DT's signal today and here are the readings I took: CBUT-DT (channel 58) was -68 dBm, FLO-TV (channel 55) was -39 dBm, K62FS (channel 62) was -55 dBm, and CHNM analog (channel 42) was -42 dBm. (I measured the peak of the visual carrier (1.25 MHz) on the analog channels, and the ATSC carrier peak (0.31 MHz) on the digital ones, for FLO-TV I measured the highest peak I could find between 716-722 MHz).

I'll also note that there is no ghosting and very little snow on the CHNM analog picture. From what I can tell I have good line of sight to the CBUT-DT tower. If I didn't, the CHNM analog picture should have been all snowy and ghosty.

K62FS is an analog repeater in Pt. Townsend, Washington. It has an ERP of 28.4 kW (compared to 30.5 kW from CBUT-DT). The K62FS transmitter is located 12.5 miles further away from my house than the CBUT-DT transmitter, and I had the antenna aimed 132 degrees off of peak for K62FS, but I still got 13 dBm more signal strength from K62FS than I got from CBUT-DT today (even though the antenna was peaked on CBUT-DT).

Unfortunately, I don't know where the FLO-TV transmitter is located or what their output power is. But I do know that I used to be able to get CBUT-DT faithfully, I also know that I still get good reception of channel 55 and channel 62 --- so I don't know why channel 58 should suddenly be a problem for the antenna. When I peak channel 55 I can get signal strength of -31 dBm, and when I peak channel 62 I can get -47 dBm.

I know for a fact that my problem is just weak RF. There isn't any interference. For whatever reason, the RF signal strength just isn't here for me. :confused:

One more thing I will say is that the signal strength I get from CHNM analog is -42 dBm. That is almost the same as I get from KBCB-DT (-41 dBm) right here in Bellingham.

If I'm not mistaken, CHNM's analog ERP is 130 kW and KBCB-DT is 165 kW. That indicates to me that my line of sight is better to Mt. Seymour than it is to Mt. Constitution, but I get everything from Mt. Constitution rock solid, and I get everything else from Vancouver except for CBUT-DT.

Thanks Jayson,

K62FS is an analog repeater in Pt. Townsend, Washington. It has an ERP of 28.4 kW (compared to 30.5 kW from CBUT-DT).


If I'm not mistaken, CHNM's analog ERP is 130 kW and KBCB-DT is 165 kW. That indicates to me that my line of sight is better to Mt. Seymour than it is to Mt. Constitution, but I get everything from Mt. Constitution rock solid, and I get everything else from Vancouver except for CBUT-DT.


I'll have to double check tomorrow but I think CBUT-DT is only 15KW ERP and CHNM analog is 100KW ERP.

I'll have to double check tomorrow but I think CBUT-DT is only 15KW ERP and CHNM analog is 100KW ERP.
Funny, the IC database says 15.6kW avg/30.5 kW peak for CBUT-DT at 615m EHAAT.

CHNM analog is 76 kW avg / 130 kW peak at the same EHAAT. (Note that 'peak' here has the FCC meaning of 'maximum ERP', and not spectral peak power.)

For Mt. Seymour stations, I think the null is into the mountain northward, so much of Metro Vancouver should be seeing the peak ERP.

That still doesn't explain a 20dB difference. Aren't NTSC and ATSC power levels measured differently (and I don't mean just the frequency of the peak)?

CBUT-DT has been a problem for me for me since about the time CKVU signed on. I used to be able to get it all the time, now I can barely get it at all on any of my receivers.

levibluewa how are your signal results for CBUT-DT in Bellingham?

2.1 signal levels are generally 70-73. Occasionally the signal spasses and the 70 will drop to 41, and continue this way....I just quit watching and the next day it'll be ok. I'm assuming transmitter glitches.

42.1 is the weakest hovering around 65 with some drop-outs. 32.1 is the strongest around 89-92. 8.1 is about 80.

levibluewa,

Generally, how reliable is CBUT-DT for you? Does it break-up very often? And have you noticed lower readings or more problems over the past few months than you did before? If you had to rank the Vancouver channels by reliability how would you do it?

Forgetting the signal meter on your tuner for a moment, how would you rank the Vancouver channels from most to least reliable (i.e. the channels with the least dropouts and glitches).

My ranking would be:

1) CHAN-DT
2) CHNM-DT
3) CIVT-DT
4) CKVU-DT
5) CBUT-DT

My rankings are as above except that I have Citytv last. I "saw" it for the first time last Tuesday, just in time for Hell's Kitchen. It needs either some more punch in the signal or I need to head up to my attic and reaim my Yagi.

(For the record, I'm on 15th St. in Anacortes, and that puts me in a straight line with Mt. Seymour.)

What I'd really like to know is, plot charts notwithstanding, if anyone in Ana is getting a good signal from KIROdt's Burlington translator.

Today's signals...

2.1 = 76
8.1 = 78
10.1 = 73
32.1 = 92
42.1 = 78

Full Power ahead! KBTC 28.1 (K24IC-D) has gone to full power from Mt. Constitution! We're thrilled to offer our programming and wanted to welcome and thank our new North Sound and Canadian viewers! Let us know if you have any questions! kbtc.org.

Michael Peters

I thought I'd have no reception issues when I bought a digital converter this week on eBay, but after reading this thread, it appears I'm sadly mistaken. All I really want is KOMO, KING, and KIRO.

Does anyone know how the LAVA HD2605 works in Bellingham? AntennaDeals claims it can receive signals from up to 150 miles away

2.1 = 67-73%
6.1 = 73-76%
8.1 = 78-84%
10.1 = no signal
17.1 = 89-92%
26.1 = not on yet
32.1 = 76-81%
33.2 = 70-73% (Citytv)
42.1 = 81-84%

Reception results for me here in Bellingham are:

CHEK-DT comes in perfectly on channel 49.
CIVI-DT comes in perfectly on channel 17.
CHNU-DT does not come in at all on channel 47 (reception of 66 was never any good either).
CIVT-DT comes in perfectly on channel 32 (much better than it did on 33).

No change in CHNM or CHAN.

CKVU is the turd in the punch bowl. Reception on channel 33 is much worse than it was on channel 47, and worse than CIVT was when it was on channel 33. I figured out this morning that I could get a good lock on KWPX from Seattle on channel 33 when CIVT switched to channel 32 and before CKVU signed on to 33, so the problem with my reception of CKVU is co-channel interference. Also CKVU's repeater in Victoria has killed KBTC's repeater on Orcas Island. CKVU has single-handedly wiped out KBTC and KWPX down here.

I gained CHEK 6.1 and CIVI 17.1 and lost KWPX: 33.1, 33.2, 33.3; K24IC: 28.1 in HD, 28.2, 28.3; and CKVU 10.1 -- so the transition was a losing proposition for me.

I don't know why Rogers had to put CKVU on channel 33. It seems to me like it would have made more sense for them to flash-cut CHNM analog to CKVU digital on channel 42. They're the same company and the antenna and transmission line would have already been there.

I also don't know why they would want channel 27 and 33 anyway. I'm sure they don't care that they're interfering with television stations in the United States, but they should care that the other side of that coin is that those same American television stations will interfere with them, and one of them (KWPX) has authorization to double its power.

There are other open channels. I don't know why Rogers would co-locate CKVU on channels used by full power stations in Seattle and Tacoma when they didn't absolutely have to. I could understand if 27 and 33 were the only channels they could have used, but they're not. That's what's so obnoxious about this.

After midnight tonight when CBC/SRC competes all their work it will be interesting to see what the new signals look like for you guys in the Bellingham area.