info & questions on SA , BLSA and meters

[gabshere]

ok i was looking and reading about BLSA and i know a few here have them some have Spectrum Analyzers

The BLSA finds the SR's ( and i guess it needs software to run and find the SR's
i'm guessing that a Spectrum Analyzer does the same ( i don't know much on a SA to comment)


I found this listing on ebay it kinda incorporates the trimax SM-2200 and i guess has a built in SA so it would be a signal finder / watchable tuner/ SA
BNW Trimax SM-2500 Sat Finder Meter Spectrum Analyzer

price range
BLSA ( on ebay $180 + s&h)
SA ( i don't know)
Trimax SM-2500 ( ebay 499+s&H)

comments , how hard / easy are the above to use

 

[qwert1515]

A spectrum analyzer and a BLSA do the same thing with the exception that the spectrum analyzer can give you the signal quality in dB values.

Both do not give you the exact symbol rate, the BLSA estimates the symbol rate.

To get the exact symbol rate you need to have a receiver that can blind search or you need an analog receiver with baseband output connected to a shortwave radio.

- I am about to run out to my OTA antenna to realign it, so I will be back in about an hour if I missed something or you have any questions.

 

[gabshere]

i guess the BLSA and SA both will see DVB-s2 signals

I suspect that will be a drawback to the trimax 2200

i'm not at home can dvb receiver find dvb-s2 signals just not display them or will it not lock them either.

 

[Stefan]

i'm not at home can dvb receiver find dvb-s2 signals just not display them or will it not lock them either.

No, a regular dvb-s receiver cannot lock dvb-s2 signals. DVB-S2 uses a different type of FEC coding.

 

[gabshere]

ok TRIMAX now has it listed on their site

and heres the manual

since i've never looked at a spectrum analyzer scan or output can someone help me with what i'm looking at ?

figure 2-16 on page 17

 

[qwert1515]

That is a horrible example / manual.

What they are trying to show is the spectrum using the IF frequency (950MHz to 2150MHz) of the LNB on the horizontal axis and signal quality/ power level on the vertical axis. (The higher the bar the stronger the signal because it is getting less negative)

(If your satellite dish is pointing at a satellite you should see the transponders, in the example it looks like they are not pointing at a satellite)

 

[skysurfer]

i guess the BLSA and SA both will see DVB-s2 signals

I suspect that will be a drawback to the trimax 2200

the BLSA and SA can see the DVB-S2 signals only in displaying that a signal exists over a given amount of spectrum. If your spectrum analzyer is really good, you can probably even tell if it's a DVB-S2 or Digiciper signal. To my HP spectrum analzyer, DVB-S2/DVB-S signals looks a little different than a Digicipher signal and if my blind scan coship gets no lock, then I can confirm it's very likely to be DVB-S2 and can hook up my
spectrum analyzer to obtain a SR figure to try (whereas others use a shortwave radio to find that same info through similar hookup methods).

If the Trimax 2200 is like my SF-3000S meter, then you can see a signal level reading exists but can't lock on the signal, so it's only useful in showing signal level readings to know there is something transmitting where the dish is pointing at and there is something at the frequency punched into the meter, but you can't lock on that signal to use BER/SN for maximum peaking performance).

 

[gabshere]

well the sm-2500 does show (as per the manual) when you have locked on a channel display the Freq, polarity, symbol rate, Vpid, Apid, Ppid, C/N, a.BER & FEC

but it will display STEP (in Mhz only allows 4 & 16), Freq., MRK (-70dBm to 10dBm) & voltage (polarity) on the Spectrum Analyzer side of the sm-2500

i don't know what a Spectrum Analyzer will give as readings as i don't have one.
does it scan the whole freq like the BLSA or is it one freq at a time ? does it give you the FEC & BER

 

[cyberdeco]

I am looking at how to configure my Trimax sm-2200 to align the star choice 107.3 anik F1.je awaits your reply

 

[linuxman]

I'm glad George opened this thread for more discussion on the BLSA.

I looked at the the thread in "another" area and was going to reply, but when I got to the bottom there was a notice stating that the thread was over a year old, and basically did I want to open an old thread, so I didn't, but I don't want to steal George's thread either.

Are all the question basically answered in this thread and in the old thread that needs to be asked?

I started reading the Turning the Broadlogic DVB-S PCI Card or ST9900 Receiver into a Spectrum Analyzer page.

Like George, I am not the greatest soldering person in the world, but have friends and neighbors that I could get to do some of the more tedious parts. I am also pretty sure my neighbor has a programming device to burn the chip. Heck, he might even have some of the parts.

I have a 10 foot finely tuned dish with a fabulous older pre-original co-rotor on it with signals that are actually better than my Birdviews with a LOS of 43W to 139W. It is all wired into my showroom/repair room with a Pansat 2500a hooked up to it and sharing space with a DSR-905/GI-650 analog receiver. Sure one of those has a tunable IF and baseband output. If not, surely out of the 15 - 20 analog receivers I have here will have it. If not I will find one. I also have a Unit ID: dead DSR-920 here and I just checked that it will still let me into the screen where you manually tune frequencies, so that might even work.

Since some of my more strenuous outside activities are going to be curtailed somewhat this might be just what I need to keep me in the middle of this hobby.

All that satellite equipment is only 15 away from my desk where I have two computers, one running Linux, and the second with Windows XP SP2 joined with a KVM switch and a 22 Inch monitor. Granted the Windows computer isn't the fastest PC in the world, but it is a P4 1.8Ghz with 768Mb RAM. It play my HD recordings from the Diamond ok, so it should work for this. Besides this is mostly scanning, not watching.

So what else do I need to get started, and will any or all of the above equipment work?

What kind of short wave radio do I need?

I am ready to jump on this project, and if I need a partner, I am sure George will jump on board, or someone else.

Let me know!

 

[qwert1515]

The soldering was not too bad, the surface mount resistors and chips were slightly annoying.
(I had done soldering before, but I had never soldered surface mount components.)

Any shortwave radio will work, it is recommended that it has SSB mode, I am using a police scanner that has AM, FM, and WFM and FM works well, I have a shortwave radio with SSB but I have not tried it out yet.

From what I have read the DSR-920 does not have baseband output.

I recently got a Toshiba TRX 2220 analog receiver for the same purpose and I can find DVB-S symbol rates as low as 2170 with the TRX's interference filter turned on.
(I don't have DVB-S2 equipment yet so I can't tell but it should be close or the same for DVB-S2)

 

[gabshere]

will the BLSA find a DVB-S2 signal ?

that would renew my interest just don't know how or why the baseband output would be needed ? or how a short wave radio fits into the plan.

the Broadlogic cards have come down in price so getting those should be easy

I always love continuing the discussion , cause i always like to learn and don't claim to know a whole lot on this subject

 

[qwert1515]

The BLSA will show any type of signal: Analog, DVB, DVB-S2, Digicipher...... (Analog signals look much different than digital signals, but DVB does not look different than Digicipher)

The BLSA does not give you the exact symbol rate, it only estimates it. (The estimation most of the time is not good enough to lock a signal, but after a while you can guess the correct value from the estimation)

So If you use the BLSA to find active signals and tune the signals on an receiver with baseband output you can tune the shortwave radio to the heterodyne frequency of the symbol rate and hear a silencing signal that is equal to the symbol rate.

Example if I find a feed on the BLSA at 11750 MHz and the BLSA estimates it to have a symbol rate of 12800, I would then tune my analog receiver to 11750 MHz and I would tune my shortwave radio to around 12800 KHz or 12.8 MHz and scan around that area until I lock a signal with no sound. If the shortwave radio locks 13.235 MHz then the symbol rate is 13235.

 

[gabshere]

great explination Qwert i'ld have to check my analog receivers to see if any has a baseband output ( which i doubt ) and then find a shortwave receiver/radio

I did see a BLSA on ebay not cheap at $180

 

[linuxman]

From what I have read the DSR-920 does not have baseband output.

I recently got a Toshiba TRX 2220 analog receiver for the same purpose and I can find DVB-S symbol rates as low as 2170 with the TRX's interference filter turned on.

I have a gently used TRX 1820 here.

How can you tell if an analog receiver has baseband output and a tunable IF?

Does anyone know what receivers have the qualifications?

 

[gabshere]

i think the 922 has it , i will see if there is a list i know the 905 & 920 don't

 

[linuxman]

I just looked at the back of the GI-650I and there is an RCA connector that has Baseband under it, so I am assuming that is the Baseband output.

I also looked in the menu, and it has a channel tuning option where you can change the frequency of the transponder and TI filter etc. Don't know if that qualifies as IF Frequency changing or not?

 

[babcea]

I have a gently used TRX 1820 here.

How can you tell if an analog receiver has baseband output and a tunable IF?

Does anyone know what receivers have the qualifications?

my toshiba trx-1800 has one,it is right under the audio-video out,and next to the data out port.

 

[qwert1515]

I just looked at the back of the GI-650I and there is an RCA connector that has Baseband under it, so I am assuming that is the Baseband output.

That will work.

I also looked in the menu, and it has a channel tuning option where you can change the frequency of the transponder and TI filter etc. Don't know if that qualifies as IF Frequency changing or not?

That will work.

The TRX-1820 will also work, here is a link to the manual for the TRX series, Pg 32 for the 1820 shows one way to manually tune the frequency.

 

[linuxman]

That will work.



That will work.

Cool!!!

The TRX-1820 will also work, here is a link to the manual for the TRX series, Pg 32 for the 1820 shows one way to manually tune the frequency.

I downloaded the manual, and I see the tuning page and I also found the connector on the back, so that's very cool. I have two capable analog units.

If we can come up with a list of what analog receivers have them I can check and see what others I have with the requirements and maybe I can clean out some space for shipping costs and Paypal transactions only.