Sencore vs Sadelco Signal Level Meters - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #1 of 35 Old 06-14-2013, 12:20 PM - Thread Starter
AVS Addicted Member
 
videobruce's Avatar
 
Join Date: Dec 2002
Location: Buffalo NY
Posts: 15,205
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 216 Post(s)
Liked: 150
The vast majority of SLM's are QAM only. That doesn't hekp anyone that wants to use one for OTA work (antenna and/or distribution). After doing a long search, the only ones (recent & current) are from Sencore & Sadelco.

What I have narrowed then down to are'
Sencore SLM 1456 CM or the newer SLM 1476CM (though the DOCSIS functions are mostly worthless to me)
or
Sadelco DisplayMax 800 (not the current stripped down 5000)

Other than OTA (VSB/ATSC) ability, I wanted 24 hr testing, PC software to xfer scans & tests to a PC, BER & MER testing would be nice (but both of these only 'emulate' those results for VSB/ATSC modulation, since there is only a QAM demodulator.
The Sencore models have between 10-15 dbmV better sensitivity over the Sadelco according to the respective specs.

The current 1476 is made by Rover in Italy as the Omnia 7. There are also two stepups (at 2x the cost). I don't know who madde the 1456, though it may be the same company.

Anyone have experience with any of these that can add some in-site?

.
.
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.
videobruce is offline  
Sponsored Links
Advertisement
 
post #2 of 35 Old 06-14-2013, 03:57 PM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,579
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
Liked: 25
Quote:
Originally Posted by videobruce View Post

The vast majority of SLM's are QAM only. That doesn't hekp anyone that wants to use one for OTA work (antenna and/or distribution). After doing a long search, the only ones (recent & current) are from Sencore & Sadelco.

What I have narrowed then down to are'
Sencore SLM 1456 CM or the newer SLM 1476CM (though the DOCSIS functions are mostly worthless to me)
or
Sadelco DisplayMax 800 (not the current stripped down 5000)

Other than OTA (VSB/ATSC) ability, I wanted 24 hr testing, PC software to xfer scans & tests to a PC, BER & MER testing would be nice (but both of these only 'emulate' those results for VSB/ATSC modulation, since there is only a QAM demodulator.
The Sencore models have between 10-15 dbmV better sensitivity over the Sadelco according to the respective specs.

The current 1476 is made by Rover in Italy as the Omnia 7. There are also two stepups (at 2x the cost). I don't know who madde the 1456, though it may be the same company.

Anyone have experience with any of these that can add some in-site?

I bought an SLM 1476 used on eBay for maybe $400 or so a few years ago. It was convenient to program a custom channel plan, which is important to me because I do a lot of hotels with mixed systems, but the digital demodulator did crap out. YMMV.

You can always get a good deal on the Sencore 1453i. Someone on eBay has a dozen with bad batteries for just $75 each. I just ordered one today. You can charge them with AC or 12 volts DC. They have a 9 pin "D": port, but I don't know what it can be made to do through that. Sencore has always e-mailed me downloadable manuals for used equipment I have bought. As you have noticed, the Sencore measures down to -45dBmV, which is very important to me as I mix in a few distant signals with my stronger local ones in large antenna systems in multiple dweling units..

Don't anyone touch the Sencore 753D with a ten foot pole. The original literature doesn't even mention digital tuning. I asked Sencore about it and they sent me a magazine format tutorial on how to build a digital channel plan on the 754D, because that is the only way to measure any digital channels but those instructions don't exactly square up with the 753D menu displays.

I think that the Sadelco uses some ultra cheap algorithm that continuously steps from one 1 MHz wide sample of a digital 6MHz wide channel and averages them. I hope I'm not confusing it with some other model I had studied a few years back.
AntAltMike is offline  
post #3 of 35 Old 06-18-2013, 02:41 PM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,579
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
Liked: 25
Quote:
Originally Posted by AntAltMike View Post

You can always get a good deal on the Sencore 1453i. Someone on eBay has a dozen with bad batteries for just $75 each. I just ordered one today.

It just came in yesterday and, as the seller had warned, it had a bad battery in it. so I simply took the battery pack out of an old broken Sencore meter and plugged it in and used it for a couple of hours today.

The 9.6v battery packs typically sell for $60 or so, but you can buy eight 1.2V Ni-cad cells for under $3 each and make your own battery pack(s) for about $20 each.

Sencore hasn't yet replied to the e-mail I sent them last night asking for an instruction manual download. The meter has a panel button labeled "Data Logger", but that might just let me store a set of most recent signal measurements.
AntAltMike is offline  
post #4 of 35 Old 06-18-2013, 07:14 PM
AVS Special Member
 
olyteddy's Avatar
 
Join Date: Oct 2005
Posts: 3,392
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Liked: 232
I've had Batteries+ build battery packs for test gear for me. They typically charge only a bit above what the batteries cost and they spot weld the tabs instead of soldering.
olyteddy is online now  
post #5 of 35 Old 06-18-2013, 09:33 PM - Thread Starter
AVS Addicted Member
 
videobruce's Avatar
 
Join Date: Dec 2002
Location: Buffalo NY
Posts: 15,205
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 216 Post(s)
Liked: 150
Quote:
Sencore hasn't yet replied to the e-mail i sent them last night asking for an instruction manual download.
I have called them and talked to a applications engineer which has been helpful. Surely more than Sadelco. rolleyes.gif

.
Quote:
You can always get a good deal on the Sencore 1453i.
That's a little stripped down for what I was looking for.

.
.
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.
videobruce is offline  
post #6 of 35 Old 06-19-2013, 09:16 AM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,579
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
Liked: 25
Quote:
Originally Posted by olyteddy View Post

I've had Batteries+ build battery packs for test gear for me. They typically charge only a bit above what the batteries cost and they spot weld the tabs instead of soldering.

Can you give me a link to their site? I Googled for them but couldn't figure out which company they were.
AntAltMike is offline  
post #7 of 35 Old 06-19-2013, 06:49 PM
AVS Special Member
 
olyteddy's Avatar
 
Join Date: Oct 2005
Posts: 3,392
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Liked: 232
olyteddy is online now  
post #8 of 35 Old 06-21-2013, 06:10 PM
AVS Special Member
 
bdfox18doe's Avatar
 
Join Date: Oct 2000
Location: Charlotte, NC
Posts: 6,475
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 83 Post(s)
Liked: 73
Quote:
Originally Posted by olyteddy View Post

http://www.batteriesplus.com/

Great site..I use them all the time..make sure to sign up for emails before ordering in order to get discount coupons. Usually the savings covers the shipping costs.smile.gif

Bob

The views expressed here are my own and do not necessarily represent those of the FOX,ABC,CBS,or CW Networks,MeTv, my employer or its parent company. Nor my wife for that matter!
bdfox18doe is online now  
post #9 of 35 Old 06-21-2013, 06:15 PM
AVS Special Member
 
olyteddy's Avatar
 
Join Date: Oct 2005
Posts: 3,392
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Liked: 232
We have an in-town one.
olyteddy is online now  
post #10 of 35 Old 06-21-2013, 06:18 PM
AVS Special Member
 
bdfox18doe's Avatar
 
Join Date: Oct 2000
Location: Charlotte, NC
Posts: 6,475
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 83 Post(s)
Liked: 73
These folks are great too: http://www.batteries.com/

Bob

The views expressed here are my own and do not necessarily represent those of the FOX,ABC,CBS,or CW Networks,MeTv, my employer or its parent company. Nor my wife for that matter!
bdfox18doe is online now  
post #11 of 35 Old 06-25-2013, 01:56 AM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,579
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
Liked: 25
Quote:
Originally Posted by olyteddy View Post

I've had Batteries+ build battery packs for test gear for me. They typically charge only a bit above what the batteries cost and they spot weld the tabs instead of soldering.

I have two local Batteries Plus stores, nearly equidistant, and so I drove to one without first price shopping, and frankly, was a little disappointed with their prices. Unfortunately, they seem to be using "house numbers" on the two models of cells that I bought, as well as for another model of cell I didn't purchase because they only had five in stock at that store but the pack I was replacing uses six, and while they did claim to have larger capacities than the cells they were replacing, their capacity values in those sizes were uncommon, making direct price comparisons impossible.

I needed eight cells for my Sencore 953i, and they measure about 16 x 48 mm and the original ones are rated as 1400 AH. Batteries Plus sold me eight 2700 AH cells for $6.79 each, loose with no tabs,, but I see that someone called Powerizer. at www.batteryspace.com, can sell me two, ten cell packs of 2200 AH batteries that look like they are that physical size for just $39.95, which is $2 per cell, and while their capacity is about 20% less than the Batteries Plus cells, it is still over 50% greater than the original ones, and they are soldered together in a pack for that price. http://www.batteryspace.com/nimhbatterypacktwo12v2200mahnimhbatterypackswithtab.aspx.

Similarly, I bought ten, sub C 2700 AH cells for $5.98 each, loose with no tabs, but Powerizer / www.batteryspace.com will sell me two, ten cell packs of sub C cells with 1600 AH capacity, which is the same as my original equipment came with, for $28.95, or about $1.45 per cell. http://www.batteryspace.com/nimhbatterypacktwo160v1200mahnimh10x23abatterypackforminirobot.aspx

Actually, because the meter that uses that latter pack is a pig with a CRT, it might be a better value for me to pay four times as much for a roughly 70% increase in capacity, but I may look around for a better value on some sub C packs with maybe 2200 or 2500 AH capacities at better prices.
AntAltMike is offline  
post #12 of 35 Old 06-25-2013, 04:59 AM - Thread Starter
AVS Addicted Member
 
videobruce's Avatar
 
Join Date: Dec 2002
Location: Buffalo NY
Posts: 15,205
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 216 Post(s)
Liked: 150
Anyone else with experience with any of these SLM's?

.
.
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.
videobruce is offline  
post #13 of 35 Old 06-25-2013, 07:31 AM
AVS Special Member
 
olyteddy's Avatar
 
Join Date: Oct 2005
Posts: 3,392
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Liked: 232
@ AntAltMike: Batteries Plus is a franchised operation. I guess the owner here gives better deals. Are both stores owned by the same people?
olyteddy is online now  
post #14 of 35 Old 06-25-2013, 08:00 AM
AVS Special Member
 
kenglish's Avatar
 
Join Date: Jan 2000
Location: Salt Lake City, UT, USA
Posts: 5,409
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Liked: 31
We have a Sencore SLM 1475. It's OK, but seems to have an easily overloaded RF amplifier. I see quite a few spurs, and the noise floor on the low-VHF Band comes up pretty high, without a filter (FM Trap), due to the local high-power FM stations.
Maybe I should have the factory check it out. Maybe it's just a bad amp.

Ken English, Sr. Engineer, KSL-TV.
"The postings on this site are my own and don't necessarily represent the Company positions, strategies or opinions."
kenglish is offline  
post #15 of 35 Old 06-26-2013, 07:38 AM
Member
 
dbdoc's Avatar
 
Join Date: Jun 2007
Posts: 103
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 16
I have the Display Max 800 at home, purchased in 2006, and the Sencore 1476CM at work, purchased in 2010. If I could have the navigation features of the 800 combined with the measurement features of the 1476, I would have one great SLM. The Sencore is at least a step above the 800, measurement wise. The 800 will give you levels for a single channel or multiple channels up to the entire spectrum of the channel plan in use. C/N is available on analogue channels only. In single channel mode, it will trace the waveform of the channel in about 8 seconds and continuously update this. The single channel mode also has the only real time level reading for antenna aiming.
The Sencore in single channel mode gives level, BER, MER, noise, and block error count for 8VSB. It can show multiple channels up to 100 channels, in bar graph mode. The spectrum analyzer mode really shines on this unit. It is real time and has adjustable bandwidth. You can realistically look at 3 adjacent channels' waveform at once and still get useable image. Most of the navigation is via a single pair of left/right arrows and select buttons. Even adding a pair of up/down arrows would make this thing so much faster to use. There are a few direct access buttons, but not near as many as the 800. In most modes, the 800 uses left/right arrows for changing channel and up/down buttons for changing sensitivity. On the 1476, you are moving a cursor around with the left/right arrows, selecting the parameter to change, then use the arrows to make the change.
When I first saw the affordable price on the 1476, I knew there had to be some compromises, and the operating/navigation system is it.
I have had no problems with either unit and both give me what I need for both cable and OTA use.
Logging and offloading for both is mostly level info for whatever channel plan is in use.
videobruce likes this.
dbdoc is offline  
post #16 of 35 Old 06-26-2013, 08:50 AM - Thread Starter
AVS Addicted Member
 
videobruce's Avatar
 
Join Date: Dec 2002
Location: Buffalo NY
Posts: 15,205
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 216 Post(s)
Liked: 150
Thanks for all of that. To reorganize it in a more readable way, would this sum things up?;

800;
navigation features
levels for a single channel or multiple channels up to the entire spectrum
single channel mode, it will trace the waveform of the channel in about 8 seconds (which is very slow)
single channel mode also has the only real time level reading
most modes, the 800 uses left/right arrows for changing channel and up/down buttons for changing sensitivity

1476;
measurement features
in single channel mode gives level, BER, MER, noise, and block error count for 8VSB
can show multiple channels up to 100 channels, in bar graph mode
spectrum analyzer mode really shines on this unit. It is real time and has adjustable bandwidth
realistically look at 3 adjacent channels' waveform at once and still get useable image
Most of the navigation is via a single pair of left/right arrows and select buttons
adding a pair of up/down arrows would make this thing so much faster to use
a few direct access buttons, but not near as many as the 800
you are moving a cursor around with the left/right arrows, selecting the parameter to change, then use the arrows to make the change.
some compromises, and the operating/navigation system is it

How about the accuracy of both? One thing you didn't mention is sensitivity. isn't eh 1476 around 10db more sensitive (lower noise floor)??
I was looking to replace my Tek RFM151 SignalScout with something more portable and newer.

.
.
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.
videobruce is offline  
post #17 of 35 Old 06-26-2013, 10:16 AM
Member
 
dbdoc's Avatar
 
Join Date: Jun 2007
Posts: 103
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 16
I don't really have a way to check accuracy and have not had both units together to compare. The 800 has a sensitivity of -30 to +60dbmv. But if it is tracing a digital waveform below -20, it shows UR (unreadable) for the average power. Frequency range is 5 to 872MHz.
The 1476 has a sensitivity of -55 to +60. Frequency range is 4 to 1000MHz.
dbdoc is offline  
post #18 of 35 Old 06-27-2013, 08:07 AM - Thread Starter
AVS Addicted Member
 
videobruce's Avatar
 
Join Date: Dec 2002
Location: Buffalo NY
Posts: 15,205
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 216 Post(s)
Liked: 150
Quote:
But if it is tracing a digital waveform below -20, it shows UR (unreadable) for the average power.
I wish I knew that a few days ago. That's seems to a deal breaker along with the extremely slow power reading level. I know you can switch over to frequency, but to change channels you have to aswitch back and the reading is completely different.
I just picked one up and my concern with the display really wasn't. It's not as bad as the photos seem to show.

.
.
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.
videobruce is offline  
post #19 of 35 Old 06-27-2013, 10:20 AM
Member
 
dbdoc's Avatar
 
Join Date: Jun 2007
Posts: 103
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 16
I am totally comfortable using either unit. I have never felt the need to bring home my Sencore to do things at home in place of the Sadelco.
One work around I found if you have a channel and don't know if it is digital or analogue. The 800 only traces the waveform for channels you mark as digital in the channel plan setup. If you mark the unknown channel as digital, the waveform will then show you if it is in fact digital with flat waveform or analogue, with the easy to spot video and audio carriers. Then you can mark it properly in the channel plan, so you get the right level measurement. Finding this work around was a relief, enabling me to get what I needed from the unit.
dbdoc is offline  
post #20 of 35 Old 06-27-2013, 10:25 AM - Thread Starter
AVS Addicted Member
 
videobruce's Avatar
 
Join Date: Dec 2002
Location: Buffalo NY
Posts: 15,205
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 216 Post(s)
Liked: 150
How/where are you using both? OTA or CATV, or both?

.
.
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.
videobruce is offline  
post #21 of 35 Old 06-28-2013, 10:04 AM
Member
 
dbdoc's Avatar
 
Join Date: Jun 2007
Posts: 103
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 16
At home: OTA and TWC. At work: OTA, TWC, custom in-house cable distribution.
dbdoc is offline  
post #22 of 35 Old 06-28-2013, 01:44 PM - Thread Starter
AVS Addicted Member
 
videobruce's Avatar
 
Join Date: Dec 2002
Location: Buffalo NY
Posts: 15,205
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 216 Post(s)
Liked: 150
Initial observations on the 800Max (no CLI);

1. The sensitivity is poor, 10db less than many others,
2. The SLM will not show levels below -20dbm, when doing a single channel scan on a digital channel. How are you suppose to aim an antenna like that??
3. Waiting for a single channel level is ridiculously long. By the time one waits for the result, anything can happen,
4. The battery pack has to be the hardest to replace compared with any other device (professional or consumer) that have seen.
5. It's heavy, bulky and boxy.
6. The GUI isn't bad. Nor is the display, better than what is pictured, though it could be brighter and have better contrast.
7. No ability to customize more than one OTA channel map.
bdfox18doe likes this.

.
.
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.
videobruce is offline  
post #23 of 35 Old 06-28-2013, 05:45 PM
Advanced Member
 
rabbit73's Avatar
 
Join Date: Apr 2008
Location: S.E. VA
Posts: 889
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Liked: 15
Quote:
2. The SLM will not show levels below -20dbm, when doing a single channel scan on a digital channel. How are you suppose to aim an antenna like that??
When I made that complaint to the Sadelco tech, he taught me how to do this:
Quote:
Originally Posted by rabbit73 View Post

When aiming an antenna you can switch from the single channel scan to the frequency mode by pressing the F1 key just below CHN/FREQ of the display. You then will have immediate feedback readings of signal strength (at center channel) to help you aim the antenna. As a bonus, this mode goes down to -35 dBmV, which is -107.8 dBm at the antenna terminals with a 24 dB preamp. The reading doesn't include the correction factor, so you must switch back to the single channel mode for that. The freq mode looks like this:

DM800544copy_1.jpg

The CH42 images in the other post aren't supposed to match, because they were made using different antennas at different locations.

It doesn't bother me at all that the correction factor (+6.8 dB according to the Sadelco tech) isn't included when using the frequency mode because I'm only looking for the max signal when aiming an antenna. As the UK hams say when adjusting their transmitter for max output: tune for maximum smoke!
Quote:
3. Waiting for a single channel level is ridiculously long. By the time one waits for the result, anything can happen,
I do have the patience to wait for the 800 to do a channel scan; it's more entertaining than many TV shows. Using the frequency mode enables me to aim the antenna for maximum signal STRENGTH, but adding the channel scan allows me to check the signal shape and pilot (at the low end) for signal QUALITY. This CH42 image doesn't agree with the one above because it was made after moving the antenna to a better location; the tuner was able to decode this signal. Forum member retiredengineer had asked me to find a way to hunt for and measure signals that were missed during a tuner scan.



I like the single channel scan of the 800 which does amplitude vs freq like a spectrum analyzer, but I wish it did more than 5.3 MHz width.

You were the one who suggested that I buy the Sadelco 800 and I'm not sorry that I did. It does what I want.
Quote:
Originally Posted by videobruce View Post

rabbit73; Go to flea-bay and search for a Tektronix RFM151 SignalScout. I have seen them sell for as low as $200.

New, 10 years ago, they sold for $2,000 to $2,500! I have two.

If you want a current model, I would recomend the Sadelco Display Max 800. The (other common) Trilithic Model Two does NOT have a OTA channel allocation table, only CATV, making it useless.

As far as I'm concered, you gave me good advice.
Thanks, Bruce!

If you can not measure it, you can not improve it.
Lord Kelvin, 1883
www.megalithia.com/elect/aerialsite/dttpoorman.html
rabbit73 is offline  
post #24 of 35 Old 06-29-2013, 04:49 AM - Thread Starter
AVS Addicted Member
 
videobruce's Avatar
 
Join Date: Dec 2002
Location: Buffalo NY
Posts: 15,205
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 216 Post(s)
Liked: 150
Quote:
When aiming an antenna you can switch from the single channel scan to the frequency mode by pressing the F1 key just below CHN/FREQ of the display. You then will have immediate feedback readings of signal strength (at center channel) to help you aim the antenna.
I realize that, but you get two completely different readings as your pics show. The other annoyance is you have to keep switching back and forth to change channels. It still doesn't change the fact it takes up to 10 seconds to get a true reading for a digital channel which is unacceptable. That may be ok on CATV systems, but surely not OTA.
Quote:
You were the one who suggested that I buy the Sadelco 800 and I'm not sorry that I did.
Unfortunately, that was based solely on user manuals since there were no comments here until the past few days, not hands on which told a different story. Recommendation rescinded.

.

.
.
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.
videobruce is offline  
post #25 of 35 Old 09-18-2013, 03:14 PM
Newbie
 
ChoiceElectroni's Avatar
 
Join Date: Sep 2013
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
We are currently looking to purchase a used Sencore SLM 1475 meter.

Does anybody out there have one they would consider selling?

If so, please contact me right away. We are interested in aquiring one.

Thank you!
ChoiceElectroni is offline  
post #26 of 35 Old 03-25-2014, 02:23 PM
Member
 
tspitz's Avatar
 
Join Date: Oct 2013
Posts: 28
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11

I just acquired a sadelco displaymax jr 2000. I want to use it for ASTC OTA TV. Can someone please advise if it works well for this-pros & cons? Any good place to find a basic demo of how it works, what modes I should use & what it measures/displays that would be most important for ATSC OTA Digital TV. A demo video would be great, if there is one out there. I googled it and didnt find much... I dont really have a technical background and havent used a signal meter before, so really need something for beginners please.

tspitz is offline  
post #27 of 35 Old 03-25-2014, 03:40 PM
AVS Special Member
 
ProjectSHO89's Avatar
 
Join Date: Feb 2009
Posts: 2,660
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 59 Post(s)
Liked: 70
Have you looked here (or contacted them directly) >>> www.sadelco.com
ProjectSHO89 is offline  
post #28 of 35 Old 03-25-2014, 06:31 PM
Member
 
tspitz's Avatar
 
Join Date: Oct 2013
Posts: 28
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by ProjectSHO89 View Post

Have you looked here (or contacted them directly) >>> www.sadelco.com


I did find a old owners manual there, thanks. I was looking for more beginners info on if its good for OTA antenna, generally what display readings are important for OTA & what they mean...  Does anyone have any experience with one of these Display Max units as it relates to ATSC OTA Antenna?

tspitz is offline  
post #29 of 35 Old 03-26-2014, 10:49 AM
Member
 
dbdoc's Avatar
 
Join Date: Jun 2007
Posts: 103
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 16
Taking a quick look at the description, this unit is mostly for checking levels and should work well for OTA. Digital tuners like a signal level between +15 and -15Dbmv. This SLM reads in Dbmv. Just select the 'off air' channel plan and you should be good to go.
You can hook an antenna directly to the unit to see where a good location for mounting would be. You can then check for loss through the cable run and any splitters. You can adjust the output of any amps so you don't overdrive the tuner.
You need to know the actual channel the stations are transmitting on. I think this unit just looks at one channel at a time, so you need to check all the channels of interest. There may be a tuning function that would make it easier to see changing levels for aiming an antenna.
Hook up a small indoor antenna to the SLM and play around with it to learn the functions.
tspitz likes this.
dbdoc is offline  
post #30 of 35 Old 03-26-2014, 06:51 PM
Member
 
tspitz's Avatar
 
Join Date: Oct 2013
Posts: 28
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by dbdoc View Post

Taking a quick look at the description, this unit is mostly for checking levels and should work well for OTA. Digital tuners like a signal level between +15 and -15Dbmv. This SLM reads in Dbmv. Just select the 'off air' channel plan and you should be good to go.
You can hook an antenna directly to the unit to see where a good location for mounting would be. You can then check for loss through the cable run and any splitters. You can adjust the output of any amps so you don't overdrive the tuner.
You need to know the actual channel the stations are transmitting on. I think this unit just looks at one channel at a time, so you need to check all the channels of interest. There may be a tuning function that would make it easier to see changing levels for aiming an antenna.
Hook up a small indoor antenna to the SLM and play around with it to learn the functions.


Thanks for the info!  Seems like this will work for my basic needs then.  So does that mean that I should shoot for DBmv as close to zero as possible. What does a high negative and high positive DBmv represent? Maybe poor signal strength, or multipath, or something??? Is there a good chart or article anyone can reference that explains that better?

tspitz is offline  
Reply HDTV Technical

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off