Signal Analyzers, Diagnostic Software, Meters, Aiming Devices for OTA

[majortom]

TSReader Lite (FREE version) displays SNR and packet error statistics at SNR levels well below "lock",
making it easier to align an antenna when it isn't yet optimally aligned...also gives you a feel for
whether you are "close" to getting reception.....

Unfortunately, TSReader Lite only works with a relatively small number of USB Tuners:
http://www.tsreader.com/tsreader/index.html
http://www.tsreader.com/tsreader/hardware.html
Be sure you are looking in the "Terrestrial (ATSC)" hardware section....

Example what ya can do with TSReader's HTML Exports (this isn't the lite version though). I hacked together a Perl Script to do HTML Exports of each channel one by one, and parsed the one line of interest to record hourly signal Quality & C/N Reports,
Script output is just a text file which can be imported to Excel.
Said I was gonna chart it sometime, haven't had it running in a while though.
U can see, my CH 38 interference has been back though, overload from nearby FM Radio Station, can tweak that out, but will probably wait for a while before I do anything about it. The dBm is really C/N and should be in dB, not dBm, apparently a typo in the ATSC BDA Source DLL's source code.
Thought this would be cool to trend out some stations across the band over time.
Could use a grep to make it easier on the eyes, but at least it works (I'm no programmer).

Snippet from log recorded few hours ago...

2010-05-11 19:10:45 Source: ATSC BDA Source<BR>Tuner: Channel 14 (473 Mhz)<BR>Signal: Locked: 100% (27.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 19:11:38 Source: ATSC BDA Source<BR>Tuner: Channel 18 (497 Mhz)<BR>Signal: Locked:  70% (19.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:50<BR><H3>PID Usage Chart</H3>
2010-05-11 19:12:23 Source: ATSC BDA Source<BR>Tuner: Channel 20 (509 Mhz)<BR>Signal: Locked:  75% (20.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:42<BR><H3>PID Usage Chart</H3>
2010-05-11 19:13:08 Source: ATSC BDA Source<BR>Tuner: Channel 23 (527 Mhz)<BR>Signal: Locked:  81% (22.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 19:13:53 Source: ATSC BDA Source<BR>Tuner: Channel 26 (545 Mhz)<BR>Signal: Locked:  92% (25.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 19:14:37 Source: ATSC BDA Source<BR>Tuner: Channel 32 (581 Mhz)<BR>Signal: Locked:  96% (26.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 19:15:22 Source: ATSC BDA Source<BR>Tuner: Channel 33 (587 Mhz)<BR>Signal: Locked:  87% (23.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 19:16:37 Source: ATSC BDA Source<BR>Tuner: Channel 38 (617 Mhz)<BR>Signal: Absent:   0% ( 0.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:01:12<BR><H3>PID Usage Chart</H3>
2010-05-11 19:17:22 Source: ATSC BDA Source<BR>Tuner: Channel 39 (623 Mhz)<BR>Signal: Locked:  83% (22.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 19:18:07 Source: ATSC BDA Source<BR>Tuner: Channel 43 (647 Mhz)<BR>Signal: Locked:  98% (26.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:42<BR><H3>PID Usage Chart</H3>
2010-05-11 19:18:51 Source: ATSC BDA Source<BR>Tuner: Channel 49 (683 Mhz)<BR>Signal: Locked:  96% (26.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 20:10:44 Source: ATSC BDA Source<BR>Tuner: Channel 14 (473 Mhz)<BR>Signal: Locked: 100% (27.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 20:11:35 Source: ATSC BDA Source<BR>Tuner: Channel 18 (497 Mhz)<BR>Signal: Locked:  68% (18.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:47<BR><H3>PID Usage Chart</H3>
2010-05-11 20:12:20 Source: ATSC BDA Source<BR>Tuner: Channel 20 (509 Mhz)<BR>Signal: Locked:  75% (20.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:42<BR><H3>PID Usage Chart</H3>
2010-05-11 20:13:04 Source: ATSC BDA Source<BR>Tuner: Channel 23 (527 Mhz)<BR>Signal: Locked:  79% (21.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 20:13:52 Source: ATSC BDA Source<BR>Tuner: Channel 26 (545 Mhz)<BR>Signal: Locked:  94% (25.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:44<BR><H3>PID Usage Chart</H3>
2010-05-11 20:14:36 Source: ATSC BDA Source<BR>Tuner: Channel 32 (581 Mhz)<BR>Signal: Locked:  96% (26.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 20:15:21 Source: ATSC BDA Source<BR>Tuner: Channel 33 (587 Mhz)<BR>Signal: Locked:  92% (25.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 20:16:36 Source: ATSC BDA Source<BR>Tuner: Channel 38 (617 Mhz)<BR>Signal: Absent:   0% ( 0.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:01:12<BR><H3>PID Usage Chart</H3>
2010-05-11 20:17:21 Source: ATSC BDA Source<BR>Tuner: Channel 39 (623 Mhz)<BR>Signal: Locked:  81% (22.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 20:18:05 Source: ATSC BDA Source<BR>Tuner: Channel 43 (647 Mhz)<BR>Signal: Locked:  96% (26.000 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:41<BR><H3>PID Usage Chart</H3>
2010-05-11 20:18:49 Source: ATSC BDA Source<BR>Tuner: Channel 49 (683 Mhz)<BR>Signal: Locked:  96% (26.500 dBm)<BR>Network Type: ATSC<BR>Run Time: 000:00:40<BR><H3>PID Usage Chart</H3>

[majortom]

here's just a day or so from the log.
Just showing three distant stations, otherwise it gets a bit cluttered.
CBLT (65 mi) and CHCH (55 mi) are NW, and WPXJ (40 mi) is almost due east.

[IDRick]

Nice work Majortom!

Are you using the standard TSreader or Professional version? Can it provide a signal strength reading in dBm as well? How difficult is it to set up the coding for storing data over time? Could be nifty way to compare antennas.

Thanks,

Rick

[majortom]

IdRick,

Thanks,
Using the standard edition, ya need the control server function
in order to tell it to tune channels.
For the perl script I installed Activestate Perl to do the scripting.

It actually started out as a project in order to populate the channel guide info in to GBPVR, from each ATSC broadcast station's PSIP, by tuning to each station once a nite, exporting the individual XMLTV.XML files for each station
from TsReader as it tuned, then once finished, combining them in to a single XMLTV.XML file, ready for import in to GBPVR.

That got old after a while, once I found an XMLTV scraper for Zap2it's website that worked with GBPVR, I stopped using it.
Then I decided to try adding on the html parse of the signal quality / C/N info. So now it does both, creates an XMLTV.xml
ready for import to many PVR like programs, and Records a Signal.txt file that ya can import to Excel.
Recording intervals are set by how often I que it up in Windows XP Task Scheduler, Accessories/System Tools/Scheduled Tasks.
Presently I have it set to hourly.

I think TsReader just reports whatever the hardware ur connected to reports, and is dependent how the .DLL ur using with TSreader interprets it. I'm using this particular ATSC BDA Source .DLL
Pretty sure it came with TsReader. The source code was included. The source I'm using reports Quality %, and C/N in dB. Not Raw Signal Strength in dBm. Would be nice to have both 'C', and 'C/N', cause then u'd have an idea of 'N' (for the weakest stations anyhow).

/*
Copyright (c) David R. Cattley (dcattley@msn.com). All rights reserved.

Module Name:

    ATSCSource.cpp

If anyone thinks they have a use for the perl scripts to parse the XMLTV (for the epg via OTA) and the HTML for signal reports I hacked together I will share them, no problem. Probably could use some polishing up from someone who
actually does programming anyway Lemme know and I'll zip it up along with a short Readme/HOWTO sometime.
Not much use unless ya have TsReader though.

[IDRick]

Thanks for your reply majortom!

I can acquire c/n readings with existing software for my video capture card. Not automated, just manual recording. I was hoping that TSreader would provide a signal strength reading plus c/n.... That would be very sweet if it did!

Best,

Rick

[majortom]

IDRick, check out post # 10 & 11 below. Out of curiousity, do ya get a Quality and a C/N from ur capture card? Any way ya can do a similar test? Doesn't need to be from TsReader. Just curious.

http://www.digitalhome.ca/forum/show...light=tsreader

[IDRick]

majortom,

Unfortunately, the software only reports c/n, correctable errors and uncorrectable errors. C/n has small flucuations over time. The errors are not tabulated and move between 0, a number, then back to 0. There's no way capture the errors.

Using an a/b switch and my Apex converter box, I can manually record c/n from computer capture card and Signal strength + Signal quality readings from the Apex. Signal strength from the Apex is highly correlated with margin to dropout (r2=0.99) and margin to dropout is highly correlated with power readings from a Sadelco meter (719c). It's a cumbersome process to evaluate all three measures. It's easiest to just record signal strength on the apex and predict margin by equation.

Best,

Rick

[bpringlemeir]

I have a 'spacelab df-200' and a 'signalcat SC-ATSC-20S' ATSC finder. The former is a real peice of garbage. The 2nd is pretty much a peice of garbage. My goal was to find the total power present at my antenna.

The analog meter on the df-200 *looked* more useful. Unfortunately, I did not see the scale or get any specs on it before ordering by mail. The range is 2-8dbu. It doesn't seem to detect anything at my antenna unless the amplification knob is turned. The behaviour is the same with/without a CM-4221 connected approx 7km from the CN tower.

The 2nd device seems to behave better. I hooked up a coax with approx 75ohm resistance at the end. It measures 60-70 dbu until I tilt it a litte and it will read 80-90 dbu (the same as when connected to an antenna and/or nothing).

Both purchases amount to about 1/5 the price of the digiair pro, but I really have nothing to show for it. I was hoping that it would have one of the RSSI chips mentioned earlier in this thread and would provide some meaningful results. Hope that helps someone.

[bpringlemeir]

Originally Posted by cogitech

I have to echo exactly what mlord and other have said re: tuners.

I just went through weeks of trying and trying to get better reception with a Kworld 120 PCI tuner. I stacked antennas, tried re-aiming, tried pre-amping, tried dist.-amping, etc. Some of it helped a bit, but not enough to justify all of my effort.

Finally I plugged the coax straight into my ViewSonic TV and BAM!, all my "iffy" channels were solid and I ended up getting channels that I didn't even know I could get before.

So then I bought an Hauppauge HVR-1250 and stuck it in my PVR. It gets all the same channels, no problem. It is a night-day difference. Seriously, I went from 18 or so (14 on bad days due to several "iffy") channels to 23 solid channels (26 if ION is ducting) just by changing the tuner.

I suspect that we are in similar geographic locations. I purchased a Hauppauge HVR-1600.

02:0a.0 Multimedia video controller: Conexant CX23418 Single-Chip MPEG-2 Encoder with Integrated Analog Video/Broadcast Audio Decoder
02:0b.0 Multimedia controller: Philips Semiconductors SAA7131/SAA7133/SAA7135 Video Broadcast Decoder (rev f0)
bpringle@pvr:~/HDTV$ dmesg | grep -i -E "kworld|Hauppauge"
cx18-0: Autodetected Hauppauge card
tveeprom 1-0050: Hauppauge model 74041, rev C6B2, serial# 6499137
cx18-0: Autodetected Hauppauge HVR-1600
cx18-0: Initialized card: Hauppauge HVR-1600
saa7133[0]: subsystem: 17de:7350, board: Kworld ATSC110/115 [card=90,autodetected]

These cards are in slots 1 and 2 of my motherboard. The Haupauge card is further from the video card. The splitter has about about 2 feet of cable to both cards. I ran several programs to detect signal strength and the Haupauge 1600 gave worst results in all cases. City-TV was marginal and with pulse audio and mplayer, I viewed both channels at the same time. The Kworld-110 card had very few pixelations. The Haupauge 1600 would loose signal and skip frames. (with/with out viewing the other channel). The last 2ft of cable could be at fault or the position of the video card. However, I definitely don't get a better signal with this card and I am out $120.

I tried to research the cards, the best 'metric' was 1st gen, 2nd gen, etc. Apparently this is the manufacturer revision of the chips and has *nothing* to do with performance between brands. Later generations may not even be better... anyways, both cards use the sa7133 driver. However, the tuner and front-ends are different. I seem to get better results with the Kworld front end.

ps.. not sure why these posts are here, but this post had motivated me to buy the Haupauge card.

[stampeder]

Originally Posted by bpringlemeir

ps.. not sure why these posts are here, but this post had motivated me to buy the Haupauge card.

Normally the tuner card posts belong in the HTPC Forum but in this case we're discussing the value some of them might have as signal analyzers/meters. We need to keep discussion to that in this thread.

[firimari]

I would like to put another vote in for the HDHomeRun networked tuner box. Mainly because of the iPhone app that allows you to check on the tuner levels. The single tuner model of the HDHomeRun is downright affordable at USD$80 on Amazon... assuming you already have an iPhone or iPod touch.
http://web.mac.com/grhowes/Generally...Signal_GH.html

[Herr Klanknratl]

I've been in contact with a company regarding producing a new swr/impedance analyzer for tv freqs. or modifying their swr analyzer to work there. They make test & measurement equipment, tuners, amplifiers, antennas etc. for amateur radio and are very reasonably priced. Design programs are sweet but there's no substitute for real world testing. What would y'all think of such a tool?

Cheers
Andy

[backpackster]

Originally Posted by firimari

I would like to put another vote in for the HDHomeRun networked tuner box. Mainly because of the iPhone app that allows you to check on the tuner levels. The single tuner model of the HDHomeRun is downright affordable at USD$80 on Amazon... assuming you already have an iPhone or iPod touch.
http://web.mac.com/grhowes/Generally...Signal_GH.html

Another way to do this with any tuner and a MAC (same principal for a PC) is to open your signal indicator program on your MAC (usually your eyetv preference - digital signal strength) and view the same HTPC/computer with a free vnc program on your iphone. I have used this to adjust my antenna, with a eyetv 250 plus and a HVR-950Q, from the top of my roof.

[elmsley]

I have my antenna hooked up to my computer using a eyeTv device and it provides me the following:

Signal Quality (in percent)
Signal Strength (in percent)
Video info (eg. 1920x1080, 17.55 Mbps, 29.97fps)
Audio info (eg. DIgital 5.1, 48kHz)

Is there a way to convert these to a dB number? I don't have a TV, but want to make some comparisons (eg. with others in this forum).

[300ohm]

Is there a way to convert these to a dB number?

Nope, not as a practical matter. It would take calibrating it to a calibrated db signal meter/signal generator setup.

I don't have a TV, but want to make some comparisons (eg. with others in this forum).

Even with TVs, different models have different meanings for signal strength and signal quality. Even between the same units, variances can exist. Theyre just relative meanings, not absolute ones. (relative to the TV youre using presently)