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iSite 6.0.96

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Ex Member
Ex Member

Sep 16th, 2011 at 7:28am  
I've run across a strange problem using iSite to put a new system online. The system is 3100 series modem. Image was loaded by service provider to match iSite software version  & provided by same.
New modem was sent to my office test site to test on an old dish, BUC, and LNB prior to taking to install site.
Put new modem on old system with opt file provided from NOC for that lat\long, correct BUC\LNB.
While trying to point system could not get iSite ant. point program to return and voltage or tone on graph.
I've trouble shot this for days with NOC and have no idea the issue.
I've tried 3 laptops with 3 downloads of software. several RX coax lines, 2 LNB, moved the dish to new location.
Finally took system to install site put on a different brand dish, BUC, LNB.  I have ant. locked on G18 using Birdog. Az. magnetic alignment looks good. Inclino meter on backplane shows right ELV. BirDog reading shows "Found" and ran peak of signal.
iSite software ant. point program shows no voltage. Reagardless if Birdog is a false positive on G18, the iSite software shows 00.00 voltage while pointing at any satellite G18 or others.
I'm using brand new cross over cable. Even tried a straight through cable.
18+ volts tested at rx in port. 18+ volts tested at end of coax to LNB.
TRied a new options file from NOC tonight, as the LNB NJR****H part number does not match availble files from NOC for LNB. They have NRJ****HK and other parts matching numeric number but not alpha at end. They sent me a new one matching specs closer to noise levels. But no change.
Tried to think of all the testing I've done but here's my question: Whats causes iSite Ant. point program to not return voltage on graph? Should I hear tone and have line red line on graph even if not hooked up by coax to LNB? Or at least get tone and red line with coax connected but not into signal energy zone from G18.
IS new LNB defective? I changed out LNB with old one but maybe it was defective as well. MAYbe crossover
cable is bad even it's new? I've used 3 Dell latop tops, 2- D430 and an X300. The x300 was used 5 years ago to put a system online with version 6.0.95 Site with no issues.
Seems it has to be a bad cross over cable- but yet I can login, load new opt files.
Could be bad modem?  I'm out of ideas and NOC does offer any help and I'm sure it's something strange or I've done something I've overlooked.

Your trouble shooting ideas are welcome here, I'm onsite- 18 hrs to get here and have to get this resolved in morning. If you have any thoughts or ideas please post here and I will look at in morning. Right now it look slike sending modem back and LNB are only solution and a return trip for putting online.


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Eric Johnston
Senior Member

Posts: 2109
Reply #1 - Sep 16th, 2011 at 11:12am  
Extract from the idirect installation manual:
"7.1 Prepare the IDU (Indoor Unit) and ODU (Outdoor Unit) for Pointing
1. If your Satellite Router is powered on, power it off at this time.
2. Ensure that the Receive IFL cable is connected from the LNB to the Satellite Router.
3. Ensure that the Transmit IFL cable is connected to the Satellite Router.
4. Disconnect the Transmit IFL cable from the BUC and connect it to the Digital Volt Meter
5. Power on your Satellite Router."

I think you should get some red or yellow reading when the LNB picks up noise from any source (e.g. itself, warm ground, hand, sun, trees, any satellite).  With the LNB powered on the minimum reading will be if the antenna beam or LNB is pointed upwards, away from any satellite. Maximum readings will occur hen the antenna beam is directed towards the sun or any powerful satellites.  A disconnected LNB or powered off LNB should give a steady zero or almost zero reading.

Complete failure to show any noise power measurement suggest that the messages from the modem to the PC are not getting through.   This could be an IP addressing problem, even if you can successfully log in and load options file.   I believe the signal noise/signal quality measurement packets use broadcast mode IP addressing.  Make sure your PC IP address mask is the same as the modem. The last IP address in the mask range is used.

Please would others contribute their ideas below....

Best regards, Eric.
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Ex Member
Ex Member

Reply #2 - Sep 16th, 2011 at 4:26pm  
Thanks for the info on IP communications. I have laptop Tcp properties onnic set up as follows: laptop ip= gateway ip + 1 or subnet gateway
Subnet of idirect modem is NOC support advised on laptop is ok. I wll change to end with 248 but belive i tried that few days ago.
There is new latop here also will try it as its diffrent brand to rule out something odd with Dell units Ive been using.
Im using iSite ver.  6.0.96 & tried version 6.0.95 also. Ive run this against older modem as well as newer modem with same opt file in each with same response of no feed back. Since there is no feedback or measurement of energy from any object I belive problem is LNB, or crossover cable, ip subnet ,ip-nic in laptop(s), or the options file is wrong for lnb. The lnb part# here does not match the lnb opt file exactly. The # for lnb opt file sent from Noc has 1 extra letter at end. Since I purchased all equipment, service, and Noc support from same company I would think the small mismatch on lnb # is normal? Its same exact lnb part I purchased from them in past.
Question- is there any way to test Lnb off the system, remove from waveguide assembly and test on the bench with volt meter? Or hook up to Birdog and point at ground, sun to see if readinds change? But since Lnb does provide feedback to birdog already(signal strength is shown, varies as dish is moved) and it locks- displays sat g18 foung and qos has been peaked proves Lnb is good? Dead Lnb wouldnt work on birdog, or correct me if wrong if it work for birdog but not for moddm and iSite.
I agree it seems Ip communication related but if anyone sees something Ive missed here please advise.
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Eric Johnston
Senior Member

Posts: 2109
Reply #3 - Sep 16th, 2011 at 7:04pm  
Testing an LNB

You can test an LNB either by DC powering it from the Birdog meter or DC powering it from the modem, via the Birdog. If you have very cheap "crystal set" type meter you must have an external DC power supply, like a satellite Tv receiver of iDirect modem.

The Birdog or cheap meter will measure the noise power coming out of the LNB.
There will be a small baseline reading once the LNB is powered on. If the LNB is pointed up at the cold sky the noise level will be the noise generated by the front end transistor (approx 67 deg K for a 0.9 dB Noise Figure LNB).

If you put you hand over the LNB input or point it at the ground the thermal noise from your warm hand or the ground (approx 293 deg K) will be measured.  You should see a small increase.

If you put the LNB on an antenna and point the beam at any satellite or the sun (8000 deg K) there will be a big increase in the noise power measurement.

Satellite identification
If you are using a Birdog, iDirect modem or satellite TV receiver, then the device has a tuneable receiver built into it and programmed to receive a carrier at say 1200 MHz with symbol rate 5 Msps. You need to input these parameters.   If you are pointed at the wanted satellite, wanted polarisation and the carrier from the satellite matches the pre-tuned parameter values then the recever will lock on to the carrier and announce "wanted carrier found !"  In the case of iDirect and Hughes HX the display goes green, the RX LED lights and the display now referes to signal quality (e.g. Signal to Noise ratio or Eb/No) rather then noise power.

LNB and Options file
I am assuming you have a simple LNB, with rectangular waveguide input (fixed polaristion) and fixed frequency conversion local oscillator (e.g. 5150 MHz for C band or 10000 MHz, 11300 MHz etc for Ku band).

The Options file specifies the L band frequency of the carrier as it comes in to the modem (e.g 1234000000 Hz or 1234 MHz)

Frequency in the satellite downlink minus the LNB local oscillator frequency equals the L band carrier frequency into the modem.

rx_freq = 1216672000     This means 1.217 GHz or 1217 MHz.
rx_acqrange = 50000      This is the range that the receiver will sweep, hunting for the wanted carrier.  Needs to be large if you have a cheap DRO type LNB.
rx_bitrate = 1100000   The bit rate plus the FEC below helps it work out what is the symbol rate. It then sets up the receiver filter bandwidth.
rx_mode = 2
rx_modtype = 1
rx_fecrate = 15
rx_scram = 1
rx_diff = 0
rx_specinv = 1    This is needed with most C band LNB since the LNB LO is high and the carrier spectrum is inverted by the LNB.

odu_rx_dc_power = 1  (Turn the DC power on for the LNB)
odu_rx_10_mhz = 0    (The LNB has its own internal reference, external reference LNB nees a 10 MHz supply)

I don't know why your Options file has the LNB type. Maybe this is to cope with complex LNBs with switchable LO frequencies and polarisations.

down_translation = 5150.000000  This might be 10000.000000 or 11300.000000 What does it say on the LNB ? What does the LNB specification say ?

IP addresses
There is a subnet with the following characteristics:
Subnet name

Gateway or PC useable IPs: Broadcast IP address

The first useable IP address is typically used as the gateway, but you can use any useable IP address for the gateway.  It is a little unusual if your gateway is .122
Any of the other useable IP addresses may be used for PCs. A PC must have different IP from the gateway. You can connect up to 5 external devices using a passive hub or switch.  Use a router so you can invent any number of additional private IPs, if you need more.
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Ex Member
Ex Member

Reply #4 - Sep 16th, 2011 at 10:55pm  
When you use antenna pointing, you should not be pointing the antenna at the satellite when you start. Move the antenna 20 degrees off the satellite then swing over to the satellite.
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