SG2100 Insertion loss

[gmd63]

If you want to determine "roughly" what/or if your motor is decreasing your Signal Quality you can do this simple test.

1.- Select a viewable channel but one in mid-range SQ. Record Level.

2.- Go to your motor with a Female to Female Coupler.

3.- Remove the coax from the H-H Motor and insert the Coupler.

4.- Return to the TV and record the SQ.

If the SQ has changed more then 4% you will want to try this remedy.

The Dollar Tree sells F connector signal splitteres for $1. Take the cover off the back of the splitter and remove the Ferrite Bead transformer. Add the components as shown in the picrures. The wire that goes straight across is the receiver to LNBF connection. The choke passes the signalling from the receiver to the H-H Motor. Note the part number and source for the RF choke. www.mouser.com .

I'm going to try this. Have the splitter and have these chokes on the way.
Has anyone else tried this? and does it work?

For only a few bucks, it is worth a try if it gets a few percent more S/quality.:up

 

[Anole]

Since you went so far back to find this thread, did you notice one more recent?

 

[gmd63]

Ahh, so you are saying use a diplexer to get the same effect?

One like in this attached picture?

 

[Mr Tony]

broke posts off of really old thread

 

[Anole]

Thanks, Ice -

Ahh, so you are saying use a diplexer to get the same effect?
One like in this attached picture?

Finding one with power passing on both sides is a ... challenge.
Most don't work that way. But if you search, they are available.
So, even if you're not handy with tools, you can try the idea.

 

[brentb636]

I notice that Rick's has the two way power passing diplexors on site.

 

[knowmiddlename]

I bypassed my SG-2100 and found no difference at all. A typical system Eb/No reading at L-Band is the same even with 10 dB of cable attenuation. It would be interesting to know how each receiver manufacturer defines "signal quality."

 

[AcWxRadar]

Super Buddy Readings

I was curious after reading this discussion, so I tested it myself using my very reliable Super Buddy meter from Applied Instruments.

I chose satellite SatMex 6 @ 113.0W, TP 12.079GHz, SR 25635 KS/s.

The motor is a DG-380 PowerTech from Sadoun and I have a 4x1 Chieta DiSEqC switch between the motor and the QPH-031 LNBF also from Sadoun. The dish is a GeoSatPro 1.2M from SatelliteAV.

I have an approximated 310 feet of cable run (250 feet of RG11 cable and 60 feet of RG6). One wall socket and one barrel connector to change from RG11 to RG6.

Here are the test results:

With all equipment (motor and DiSEqC switch) inserted:

-62.6 to -62.7 dBm
-13.8 to -13.9 dBmV
46.1 - 46.2 dBuV
77 - 78 IRD
10.3 - 10.5 C/N (Eb/No)
11.6 - 11.8 Es/No

AZBox meter with 0.9.3501 image = 70% SL / 61-62% Q
Coolsat 5K with 0.04 firmware = 75% SL / 73-75% Q

With motor and DiSEqC switch bypassed (connected direct to LNBF):

-56.5 to -56.6 dBm
-7.7 to -7.8 dBmV
52.2 - 52.3 dBuV
81 - 82 IRD
10.5 - 10.6 C/N (Eb/No)
11.8 - 11.9 Es/No

AZBox meter with 0.9.3501 image = 75% SL / 62-63% Q
Coolsat 5K with 0.04 firmware = 82% SL / 74-76% Q

In my opinion, the attenuation of the signal is extremely negligible and this with bypassing both the switch and the motor.
I wouldn't bother with any elaborate cabling or filters as I don't see that it is at all necessary (except for experimentation).

An SG-2100 motor is essentially the same critter as the DG-380 in this specific regard. I have several of the SG-2100's as well and have never noticed any signal limitations simply due to the motor being in the RF circuit. I guarantee that the test results would be so identical that no one would be able to discern the difference.

RADAR

 

[Smith P.]

RADAR,

While those -6 dB is negligible for your sat/tpns, for others with low signal level, the 6dB (4X) would be beneficial.

 

[knowmiddlename]

Radar,
Nice detailed test!

 

[1ADAM12]

Ahh, so you are saying use a diplexer to get the same effect?

One like in this attached picture?

Some of the spec 3 dB loss.