Antenna Testbench

[archive10]

After figuring out how to mount the Triax 2140 on the Laminas tripod, I figured the arrangement is actually great for trying out various dishes and mounts on.



Not only is the dish in a reasonable height, I can also change the mounting pole to adapt to the requirements of the mount (50-60-75mm etc). The mounting tube is resting an old bracket for a microwave dish I had lying around. (Knew it would be useful someday!)





Making sure the mounting tube is vertical initially took a bit of fiddling, but I've gotten the hang of it now.






Can now try various dishes and mounts without having to bolt the to wall!

 

[RimaNTSS]

Good job Sten!
Question: If you need to change azimuth of the vertical pipe for a small amount, lets say 0.5*, how will you do that?
My answer would be: You need a small device- long handle. When you grab end of this handle and pull/push it little bit then azimuth will be changed very precise.
I have such a handle, it is in yellow oval.

Add: And, I think after you gang heavy dish on the pole, it's plumbness can change. I maybe wrong here.

 

[archive10]

So first up as test rabbit is...
The cheapest motor I could find on the web. Really.

Purcahsed this from satkontor.de, and it arrived within a reasonable time-frame (5 days).








Needed to attach something to it, and didn't want to go for the Channel Masters just yet, meant that I went rummaging in the back for something, and came up with a 40cm Gibertini.







Now this is not what you'd normally put on a motor, but I just thought - let's give it a go...

Got reception on the meter from:
- 28.2 (on the Europe beam)
- 13E (due-south)
- 19.2E (full power - man that sat overshadows everything)
- 5E (Viasat Country)
- 30W (Hispasat)

Didn't bother to hook-up STB. Dish too small

 

[archive10]

Good job Sten!
Question: If you need to change azimuth of the vertical pipe for a small amount, lets say 0.5*, how will you do that?
My answer would be: You need a small device- long handle. When you grab end of this handle and pull/push it little bit then azimuth will be changed very precise

I think you mean elevation here. Until now, the dish mounted had posed no strain on the elevation angle of the mounting tube. (Hey, it's only a 40 cm alu dish).
Elevation is controlled throuh adjusting the mounting brackets, and they feel fairly sturdy.
I'll report back once I've fitted some larger dishes...

 

[RimaNTSS]

No, I meant azimuth. Precise azimuth adjustment is very important for motorized antenna. Bigger antenna more important the precision of azimuth adjustment.
I marked in yellow squares situations when azimuth adjustment is especially important

 

[Tururu]

@st1.
Confirm in the engine manual, this motor has no reset to indicate that it is to zero, it is done by turning it off (removing power and connecting again).
I mention it, you can go crazy with some test if you turn off and ignite takes the reference point wrong.
They gave me one, it has 2 pushbuttons for the right/left turn and where I would have the reset point, it has the led indicator of power/activity.
The photo does not look good, it's like the engine.?
-------------
Confirma en el manual del motor, este motor no tiene reset para indicar que esta a cero, se realiza apagando (quitando alimentacion y conectando de nuevo).
Lo comento pues te puedes volver loco con alguna prueba si apagas y al encender toma el punto de referencia mal.
Me dieron uno, tiene 2 pulsadores para el giro derecha/izquierda y donde tendria el punto para hacer reset, tiene el led indicador de alimentacion/actividad.
La foto no se ve bien, es como este el motor.?




PS: Back in the drawer of the junk/De nuevo en el cajon de los trastos.

 

[archive10]

No, I meant azimuth. Precise azimuth adjustment is very important for motorized antenna. Bigger antenna more important the precision of azimuth adjustment.
I marked in yellow squares situations when azimuth adjustment is especially important View attachment 110003

Ah, I see. Sorry - I wasn't thinking of rotating the actual vetical pipe.
I usually just rotate the mount to achieve the same effect (I put a pipe muffler clamp underneath if the mount is like the one on the motor. The Prodelin, Channel Master and Luxor dishes all fit on top of the pipe.

Never really thought about the azimuth as being crucial. For me, 13E is exactly south (179.3 degrees), meaning I can get south-orientation fairly easily.
How do you generally distinguish (i mean practically when adjusting the dish) between azimuth error and too little / too much in- and declination?

 

[archive10]

@st1.
Confirm in the engine manual, this motor has no reset to indicate that it is to zero, it is done by turning it off (removing power and connecting again).
I mention it, you can go crazy with some test if you turn off and ignite takes the reference point wrong.
They gave me one, it has 2 pushbuttons for the right/left turn and where I would have the reset point, it has the led indicator of power/activity.
The photo does not look good, it's like the engine.?

[...]
PS: Back in the drawer of the junk/De nuevo en el cajon de los trastos.

It is exactly that motor.
Same buttons and connectors.
The symptom you describe does ring a bell - I did notice that telling the motor "goto 0" positioned it in strange places a few times.
Are you saying that this motor forgets where 0 is everytime you power it off?
Then surely, it does not support proper DiSEqC and USALS!

 

[Tururu]

...The symptom you describe does ring a bell......Are you saying that this motor forgets where 0 is everytime you power it off?
Then surely, it does not support proper DiSEqC and USALS!

Yes.
I observe it when trying to fine tune a position in the motor (I use the DreamBox800 by the tuner output that I connect to the spectrum analyzer, in the VU + DUO2 I only have inputs, have dual tuner), change equipment and lost the position, 2 receivers had the same latitude and longitude data.
The trick is to zero the engine, disconnect and connect the power supply, already has the zero reference, then send the satellite you want.
It works well in DiSEqC 1.3 / Usals, the problem is its way of working.
In the old engines, gradually lose the reference of position 0, touch to zero and climb where you have the motor (roof) and press the rest, working well.
With this engine, you do not have to climb to the roof and carry out the process.
Some are delighted with the solution (less problems with the neighbors), for the lunatics of the satelite like us, is a "shit".

I bought it a few years ago as a Rover white brand (35 €), in the documentation and in the box supports DiSEqC 1.2 (logo in large) and in features, indicates that it supports GotoX.
Conclusion, you are not certified for DiSEqC 1.3/Usals (that's why it's very cheap).
PS: Question to adapt, I removed it and put another SG2100A.
-------
Asi es, si.
Lo observe cuando al intentar afinar una posicion en el motor (uso la DreamBox800 por la salida del tuner que conecto al analizador de espectro, en el VU+DUO2 solo tengo entradas, tiene tuner dobles), cambie el equipo y perdi la posicion, los 2 receptores tenian los mismos datos de latitud y longitud.
El truco es mandar a cero el motor, desconectar y conectar la alimentacion, ya tiene la referencia del cero, entonces mandar al satelite que quieras.
Funciona bien en DiSEqC 1.3/Usals, el problema es su forma de funcionamiento.
En los viejos motores, poco a poco pierden la referencia de la posicion 0, toca mandar a cero y subir donde tengas el motor (tejado) y pulsar el rest, funcionando bien.
Con este motor, no tienes que subir al tejado y realizar el proceso.
Unos estan encantados con la solucion (menos problemas con los vecinos), para los locos del satelite como nosotros, es una "mierda".

Lo compre hace unos años como marca blanca de Rover (35€), en la documentacion y en la caja soporta DiSEqC 1.2 (logo en grande) y en caracteristicas, indica que soporta GotoX.
Conclusion, no estas certificado para DiSEqC 1.3/Usals (por eso es muy barato).
PD: Cuestion de adaptarse, yo lo quite y puse otro SG2100A.

 

[archive10]

Conclusion, you are not certified for DiSEqC 1.3/Usals (that's why it's very cheap).
PS: Question to adapt, I removed it and put another SG2100A.

I know, I know.
I just purchased this motor as a diversification, as I've never fiddled with a H2H before, only used polar mounts with dumb actuators and V-boxes.
I was considering a Stab, but as this is just for experimentation, I didn't want to spend too much on it.
A bit like seeing how far I could go with the cheap stuff...

 

[archive10]

All-right, more experimentation: Change of equipment.

Obtained a cheap, I mean, good-value-for-money Telesystems TM80 dish (effective 75 cm).
It has an offset angle of 26 degrees, which explains the "ovalness" of the dish compared to others.

This should be a bit more directional than the 40cm Gib, allowing me to distinguish more satellites around the really strong ones such as 19.2E.









A plastic rear-structure for a change.
Feels a bit strange tightening the nuts knowing that tightening too much might crack the back structure....







Nevertheless, had some good reception on the initial try on this dish.
Reception from 30W to 45E, probably limited by the out-dated transponder list in the meter (SatLook Lite).
Think I will try this dish attached to a receiver...

 

[Tururu]

@st1
To have fun adjusting antennas comfortably in the garden, is perfect, works well.
You know the little problem/defect you have, no problem, just keep it in mind.
I went crazy to change the receivers and see that I lost the satellite (more crazy than normal).
-------
Para divertirte ajustando antenas comodamente en el jardin, es perfecto, funciona bien.
Sabes el pequeño problema/defecto que tiene, no hay problema, solo tenerlo en cuenta.
Me volvia loco al cambiar los receptores y ver que perdia el satelite (mas loco de lo normal).

 

[archive10]

I'm having strange deterioration of horizontal performance on an LNB.
The LNB is a IBUS attached to the 75cm Telesystem dish (as pictured above).
It is fed through the DiSEqC motor, as normal.
On a power-cycle, everything returns to normal.

But when checking again after a day or so, spikes appear in the lower 2/3s of horizontal scans.

I will go and bypass the motor later, but let's see if anyone can guess whether it's the LNB or the Motor that screws things up...

The first scan is after power cycle, the second is after a day.
The spikes don't appear in the same places, and the depth are not the same from scan to scan.
It's clearly failure of some of the electronics in a device, but can you guess which one?

 

[Terryl]

The motor is passive at the higher frequency's of the satellite transponders, all it responds to is the 22 KHz from the receiver.

It may be a voltage drop (or spike) as the LNB is sensitive to stuff like that.

What type/brand coax are you using and do you know the spec's on it?

As you mentioned, a direct connection to the LNB with the dish fixed on that same satellite and transponder is a good way to test if the motor or LNB is at fault.

 

[John Pykett]

hmmm you are lucky you have this kind of motorized setup because i can only get 9 sats on my motorized because of my view south

 

[archive10]

What type/brand coax are you using and do you know the spec's on it?

Triax double-shielded cable. Not the best, but also not worst. Reasonable confidence.
Installed 7 years ago. Might worry about water ingress - it's PVC, not PE, outer shielding.
Nevertheless - I reason it is not the cable... there is no or little evidence of an effect on verticals.
The 13V vs 18V should not really be that frequency dependent, so I think more of a fault in the electronics.

 

[archive10]

As you mentioned, a direct connection to the LNB with the dish fixed on that same satellite and transponder is a good way to test if the motor or LNB is at fault.

Just did that - same behaviour. And I noe learned that the spiking sets in after 5 minutes, no need to wait several hours...

Is probably naff LNB. Will replace tomorrow with something else, and retry the scans.

PS: Now there seems to be spikes even on the verticals!

 

[Channel Hopper]

hmmm you are lucky you have this kind of motorized setup because i can only get 9 sats on my motorized because of my view south

Is there a tree in the way of the others ?

 

[John Pykett]

Is there a tree in the way of the others ?

im not sure ill try to get a picture of the garden tommorow

 

[Terryl]

Is your coax grounded???