new 1.2 meter dish and 12 footer

[LocutusOfBorg]

Why is the dish rotated?

Last time I checked, that's normal. My 90 cm on a HH90 rotates like that.

Is that the correct bracket from SatelliteAV?

It's the bracket that came with the dish.

 

[LocutusOfBorg]

Now that the temperature is above 80 degrees, I've lost Azteca on 97W again. I watched it for awhile around 0800 MDT this morning but now it's gone. H&I on 101W is gone again also.

 

[primestar31]

Why is the dish rotated?

Is that the correct LNB bracket from SatelliteAV?

It's on a polar mount, yet it's an offset dish. So.... if it's not pointed true South, the face of it is going to look "rotated" depending on which satellite he's presently pointed at.

Johnny, try this: Aim at 99w, whatever your strongest signal there is.
REMOVE the conical scalar completely from the lnbf. Tune the lnbf forward / backward, and even twisted whatever degree it must be for 99w at your house. Try to get absolutely ALL the signal you can gather that way. Tighten it all down when you think you've got it. Double-check it to make sure nothing changed when you did the last crank down. THEN re-install the scalar. Do NOT touch the lnbf's position anymore, only slide the scalar in or out, and see if you can peak the signal even more.

Years ago when I did this, my scalar was all the way to the very end of the lnbf for my best signal.

With a smaller dish such as this, it's going to see probably around 5-6 degrees of sky. Since the satellites are only 2 degrees apart, that means sats to either side can interfere, depending. I bring this up, because that ALSO means that maybe pointing slightly to the LEFT or RIGHT of the sat you actually want to get, might work better!

In other words, you want to slightly "detune" any possible interfering satellite to either side, yet still get the signal you want if possible.

 

[comfortably_numb]

This is what mine looked like with a C-band LNB on it:

 

[LocutusOfBorg]

Johnny, try this: Aim at 99w, whatever your strongest signal there is.
REMOVE the conical scalar completely from the lnbf. Tune the lnbf forward / backward, and even twisted whatever degree it must be for 99w at your house. Try to get absolutely ALL the signal you can gather that way. Tighten it all down when you think you've got it. Double-check it to make sure nothing changed when you did the last crank down. THEN re-install the scalar. Do NOT touch the lnbf's position anymore, only slide the scalar in or out, and see if you can peak the signal even more.

As soon as I took the scaler off, the C/N increased by 1 dB. I got another 0.5 dB by adjusting the LNBF in/out and the polarity. So, I installed the scaler and no matter how I adjusted I couldn't get back to the peak. The peak was 7.5 but I could only get 7.0 with the scaler installed. When I took the scaler off again I got 7.5.

Years ago when I did this, my scalar was all the way to the very end of the lnbf for my best signal.

With a smaller dish such as this, it's going to see probably around 5-6 degrees of sky. Since the satellites are only 2 degrees apart, that means sats to either side can interfere, depending. I bring this up, because that ALSO means that maybe pointing slightly to the LEFT or RIGHT of the sat you actually want to get, might work better!

I noticed that because the osmio was scanning in transponders from adjacent satellites.

In other words, you want to slightly "detune" any possible interfering satellite to either side, yet still get the signal you want if possible.

I'll probably end up using the 1.2 meter for Ku and installing the TEK 12 footer (when the weather gets cooler). Anyway, we'll see how it goes.

 

[RimaNTSS]

This is what mine looked like with a C-band LNB on it

Seems quite complicated , but at the end of the day, if it works, why not.
And it is friendly dog, friend of you!

 

[LocutusOfBorg]

Just tried my spare LNBF and got the same results.

 

[LocutusOfBorg]

This is what mine looked like with a C-band LNB on it:

Is yours motorized? If so, how well does it perform?

 

[LocutusOfBorg]

Seems quite complicated , but at the end of the day, if it works, why not.
And it is friendly dog, friend of you!

Is yours motorized? If so, how well does it perform?

 

[LocutusOfBorg]

With a smaller dish such as this, it's going to see probably around 5-6 degrees of sky. Since the satellites are only 2 degrees apart, that means sats to either side can interfere, depending. I bring this up, because that ALSO means that maybe pointing slightly to the LEFT or RIGHT of the sat you actually want to get, might work better!

I've noticed that the osmio4k autofocus doesn't work too well with that big of a beamwidth.

 

[RimaNTSS]

how well does it perform?

TBH, I have no idea how to measure performance. But if I say something like "it performs well" I will be right

 

[primestar31]

I've noticed that the osmio4k autofocus doesn't work too well with that big of a beamwidth.

Yeah, I've never had much luck with that "autofocus". It's never got me anything I didn't already have perfectly peaked.

 

[LocutusOfBorg]

TBH, I have no idea how to measure performance. But if I say something like "it performs well" I will be right

You're a funny guy. So, you're from Latvia. I guess you wouldn't be much help with North American satellites. Hmm, I wonder if I should suggest that this forum display the flag for each persons country. State/Province flags might be interesting also.

 

[LocutusOfBorg]

Nothing to do with the heat sink thermal dissipation qualities on a LNBF.

Then what is the purpose of the heatsink? I read in some other forum that it's a useless item. Is that true?

Physics 101... Thermal noise increases and the atmosphere attenuates and depolarizes during the day and especially during the summer months. Also may be experiencing a slight attenuation by particulates ((ie. smoke and ash drifting across the continent). SNR improves during the cold season.

OK so it can't be equipment failure. If it isn't equipment failure then I'll have to scrap my plans for using a 1.2 meter dish. I was hoping to get adequate performance for the services that the wife watches but that doesn't look possible with the 1.2 meter. It would've been great to have a smaller dish in the backyard but I need something that's reliable. If I had the bucks I'd experiment with different size antennas and use the smallest ones that get the job done. I suppose experimenting with different lnbf's might not be a bad idea also. Too bad there's not much of a selection in NA.

 

[Titanium]

Then what is the purpose of the heatsink? I read in some other forum that it's a useless item. Is that true?

In this day and age, I am certain that you don't believe everything that you read on a forum.

The fins reduce the cavity temperature when the ambient temperature is lower than that of the cavity with the heatsink is mounted in the shade of the feedhorn or a feed cover.

My point was that the loss of these marginal signals during the heat of the day is due to environmental conditions that affect the signal path.

 

[arlo]

yeah. so since you've tried it all so far. you get better signal with the scalar off but get adjacent sat interference. did you try for giggles a c-band scalar?
hey. it can't hurt, right? that's a hell of a small dish for c-band. kudo's for trying.

 

[LocutusOfBorg]

yeah. so since you've tried it all so far. you get better signal with the scalar off but get adjacent sat interference. did you try for giggles a c-band scalar?
hey. it can't hurt, right? that's a hell of a small dish for c-band. kudo's for trying.

If it wasn't for the loss of the desired services during the daytime this 1.2 meter would fit the bill. Anyway, I get a new scaler with every new LNBF so I got lots of them laying around. I guess I'll at least experiment with them. I have Chapparel and Titanium scalers along with a couple others. The adjacent sat interference makes me think that losing half a dB might be worth keeping the conical scaler on. I am kinda wondering if a lower noise LNBF would overcome the daytime conditions. I've been reading through forums about the performance of various LNBF's and a lot of them are no longer manufactured or someone recommends a standard LNB that's designed to work with a corotor (from the good ol' days). I don't know if the newer LNBF's with a 3.7 to 4.2 GHz passband would help. The single output Titanium is $42 which wouldn't kill my budget. It's only fiat currency......

 

[primestar31]

danristheman Dan, you are the resident expert in small dish C-band reception. I know you've not been around much lately, but do you have any advice for Johnny to help him tweak his 1.2m dish a bit more?

 

[LocutusOfBorg]

I guess I'm making progress. The only real change I made was installing a standard scaler on the LNBF and so far I've been able to watch the desired channels even though it was 100 degrees today. It's about 90 right now and the services are still there. I don't know why I couldn't get the same result with a conical scaler. I'll have to test this every day for a week and see if the results are solid before turning it over to the wife.

 

[LocutusOfBorg]

It's 102 degrees right now. Univision on 91W is coming in but breaking up - but usable. Azteca on 97W appears solid as well as H&I on 101W. Working better than a couple of days ago but there's room for improvement. Not sure if I can get things working better. Maybe I should run out and give the 1.2 meter some ice tea......

We have cooler weather coming and maybe that'll solve my problems...