Upper C-Band 4.5 to 4.8 GHz

[moonbase]

...For a future test, it might be interesting to compare a C1-PLL instead of a wideband C1W-PLL. While our filtering will attenuate frequencies above 4.2HHz, the C1-PLL is tuned for 3.7- 4.2GHz band and not balanced for the entire 3.4 - 4.2GHz range like a wideband LNBF.

I purchased a Titanium C1-PLL LNBF shortly after I ran the tests and found it gave improved performance over the Titanium C1-WPLL LNBF. I will possibly repeat the test if I move upwards to a larger dish.

If you (Titanium) decide to get a 3.7 - 4.8 GHz twin probe LNBF manufactured I would certainly buy a couple of them. However, I realise that there has to be a minimum order quantity for a production run.

At the moment with 40.5 West I am on the threshold for a lock with one of the extended C Band frequencies (4581 L) and under a lock for the other one (4641 L). I need to go up in dish size to get both to lock.

 

[Babadem]

I was wondering what LNB/LNBFs were available that cover that range of frequency... I'm pretty sure there's a Norsat LNB, at Norsat price, which makes it a bit hard to justify the expense considering that there's not much on those frequencies.

Is anyone aware of a more affordable option?

Tek2000 has an LNBF that has ambiguous description, that made me think that it would cover that band, but after looking it up from other resellers, it's seems it's just a stacked LNBF that uses a 5750 LO to cever the second polarity

Has anyone considered modifying an existing regular C-Band LNB to change the LO to 5750 MHz? I'm guessing that would be difficult without proper measuring equipment, but maybe not impossible?

I never knew this existed. Learn new things everyday.

 

[Babadem]

Developed a 3.7 - 4.8GHz PLL model several years ago that is currently under license by a satellite corp. The license will expire in 2020 and may manufacture under Titanium Satellite brand if the market expands.

At this time, very few services have footprint in the US or Canada using this frequency range. The South American footprints cover the southern regions of the US. Had a useable, but with very low SNR in Northern California.

The feed and probes for a standard LNBF provided poor performance in the higher range. While the stubs can be shortened for the higher frequency, the larger feedhorn cavity was problematic and cross pol was quite poor.

There are several satellite equipment resellers in South America with inexpensive LNBF options.

BTW... the Anhui Bowei 4500 - 4800 MHz LNBF model is not only cheap, but also features absolute crap performance. Yes, this is the same factory that cloned our PLL LNBF and now directly sells on Ebay.

@ the red Highlighted: Any update on this?

 

[Titanium]

@ the red Highlighted: Any update on this?

The licensing agreement was renewed. Little demand in NA market to manufacture and stock a similar model.

You can purchase high band C-band LNBFs from South America and I've seen them sold on Ebay with shipping from China. Not sure of the quality, but the cost is reasonable if you want to experiment.

 

[k4otl]

I know this is a long dead thread, but with talks of spectrum auctions and such, is 4.5-4.8 still viable? Or was it auctioned off as well previously?

 

[Brct203]

I know this is a long dead thread, but with talks of spectrum auctions and such, is 4.5-4.8 still viable? Or was it auctioned off as well previously?

as far as I know, there's capacity in that band on 4 satellites that cover North America:
- Hispasat 6 @30W (not 100% certain, and I have never seen any info of it being used)
- SES6 @ 40W (it was being used at some point, but not seeing anything listed at this time)
- Amazonas @ 61W - according to PortalBSD there are data transponders
- Eutelsat 65 WestA @ 65W - dozens of mostly Brazilian channels

Note that I'm not able to receive it so this information is based on what's on Lyngsat and PortalBSD

So it looks like it's alive and well, but not growing. It's also clear it's not aimed at North America, we just happen to be included in the footprint, at least partially

I don't know if that band is licensed to satellite use in North America, so it might not even be an option to be actively used here.

On the technical side, with a regular C-band LNB with LO=5150 MHz, the 4.5-4.8 band translate to 350-650 MHz, which is of course too low for regular satellite receivers. So I have hooked up an SDR dongle to be able to look at the spectrum. While most LNBs filter that band out, I have an old Norsat that does not, and was able to see at least part of the transponders on 65W. I tried adjusting the LO frequency in the LNB, but could get only minor adjustments (about +/- 10 MHz), far from what would be needed

 

[one_db_compression]

as far as I know, there's capacity in that band on 4 satellites that cover North America:
- Hispasat 6 @30W (not 100% certain, and I have never seen any info of it being used)
- SES6 @ 40W (it was being used at some point, but not seeing anything listed at this time)
- Amazonas @ 61W - according to PortalBSD there are data transponders
- Eutelsat 65 WestA @ 65W - dozens of mostly Brazilian channels

Note that I'm not able to receive it so this information is based on what's on Lyngsat and PortalBSD

So it looks like it's alive and well, but not growing. It's also clear it's not aimed at North America, we just happen to be included in the footprint, at least partially

I don't know if that band is licensed to satellite use in North America, so it might not even be an option to be actively used here.

On the technical side, with a regular C-band LNB with LO=5150 MHz, the 4.5-4.8 band translate to 350-650 MHz, which is of course too low for regular satellite receivers. So I have hooked up an SDR dongle to be able to look at the spectrum. While most LNBs filter that band out, I have an old Norsat that does not, and was able to see at least part of the transponders on 65W. I tried adjusting the LO frequency in the LNB, but could get only minor adjustments (about +/- 10 MHz), far from what would be needed

While this isn't a FCC list, it should be helpful.

Authorized and Approved Canadian Satellites

Conditions of Licence for Satellites in Operation. Approvals in Principle for Satellites Not Yet in Operation

ised-isde.canada.ca

List of foreign satellites approved to provide fixed-satellite services (FSS) in Canada

List of foreign satellites approved to provide fixed-satellite services (FSS) in Canada

ised-isde.canada.ca

Also, a transponder's technical capacity of operating in a band doesn't necessarily mean there is an associated license to operate. You would need to deep-dive further on the spacecraft details.

Everyone else's mileage may vary.

 

[arlo]

On the technical side, with a regular C-band LNB with LO=5150 MHz, the 4.5-4.8 band translate to 350-650 MHz, which is of course too low for regular satellite receivers. So I have hooked up an SDR dongle to be able to look at the spectrum. While most LNBs filter that band out, I have an old Norsat that does not, and was able to see at least part of the transponders on 65W. I tried adjusting the LO frequency in the LNB, but could get only minor adjustments (about +/- 10 MHz), far from what would be needed
c band

Another consideration is the microstrip bandpass filter. A magical world at least for me.
I haven't swept a c band satellite that is "busy". During football season 89W would be interesting because almost every time you scan it, there are new tp's and sr's popping up. Sometimes (usually) only for the event. I blindscanned it last night and it was almost dead.

A TinySA is fun to play with as is something like the SDRPlay spectrum analyzer application. A fancy bias-tee isn't needed for either one because you're non doing lab work. You're snooping around.

A signal source is needed. A 'junker' or spare c band lnbf and capable signal generator/service monitor with generator, or known active transponder in the extended band would let you dick around with the bandpass filter. I'd have to look deeper into the block diagram and photos of the pc boards.
Ku band lnbf teardown and LO mods are all over the 'net. C band? Not so much.
Who knows. I'm sure the bandpass filter isn't a "brick wall" and there is a bit of an attenuation slope on both sides of the filter.
A bypass capacitor? Jumper the filter? X-Acto knife to break the filter traces in small chunks and see if upper band signals increase using an SA and normal lnbf. You never know.