C238 LNBF Dual Output vs. C2-PLL with 5G WiMAX 4G LTE Radar Interference Filter

mr3p

mr3p

Thread Starter
SatelliteGuys Pro
Pub Member / Supporter
Jan 1, 2010
1,229
202
West
Hi Titanium,
I happen to visit your store and noticed you had added new LNBFs which I am guessing means you are expecting inventory soon. I currently have your C2PLL with low band filter LNBF and was just trying to compare specs to see differences. As I always appreciate learning from you, could you give us your thoughts on how they compare and any pros or cons? I see the C238 has a narrower IF range which might impact reception of some current feeds (mostly Spanish) until they are relocated. Other than higher IF cutoff, are there differences or advantages of the C238 filter? Is the C238 non-PLL and how might that matter? Thanks as always for bringing us new products.
 
Last edited:
mr3p

mr3p

Thread Starter
SatelliteGuys Pro
Pub Member / Supporter
Jan 1, 2010
1,229
202
West
C2-PLL with 5G WiMAX 4G LTE Radar Interference FilterC238 LNBF Dual Output - 5G Red Band Pass Filter
Input Frequency Range3.70 ~ 4.20GHz3.80 ~ 4.20GHz
Output Frequency Range950 ~ 1450MHz950 ~ 1350MHz
L.O. Frequency5150MHz5150MHz
Noise Temperature15K typical15K typical
LO Stability± 50Khz± 1MHz
LO Phase Noise @ 1Khz-72dBc-65dBc
LO Phase Noise @ 10Khz-81dBc-95dBc
LO Phase Noise @ 100Khz-90dBc-110dBc
Conversion Gain65dB typical65dB typical
Gain Flatness±4dB±1dB/36MHz?
Gain Variation±1dB / 27 MHz±1dB?
Image Rejection-45dB-50dB
Crosstalk Isolation20dB typical20dB (min)
Current145mA [max]150mA [max]
Output VSWR2.0 : 12.5 : 1
Temperature Range-22 ~ +140°F / -40 ~ +60°C-22 ~ +140°F
 
  • Like
Reactions: Titanium
Captain Midnight

Captain Midnight

SatelliteGuys Pro
Sep 16, 2019
476
311
Greers Ferry, Arkansas
C2-PLL with 5G WiMAX 4G LTE Radar Interference FilterC238 LNBF Dual Output - 5G Red Band Pass Filter
Input Frequency Range3.70 ~ 4.20GHz3.80 ~ 4.20GHz
Output Frequency Range950 ~ 1450MHz950 ~ 1350MHz
L.O. Frequency5150MHz5150MHz
Noise Temperature15K typical15K typical
LO Stability± 50Khz± 1MHz
LO Phase Noise @ 1Khz-72dBc-65dBc
LO Phase Noise @ 10Khz-81dBc-95dBc
LO Phase Noise @ 100Khz-90dBc-110dBc
Conversion Gain65dB typical65dB typical
Gain Flatness±4dB±1dB/36MHz?
Gain Variation±1dB / 27 MHz±1dB?
Image Rejection-45dB-50dB
Crosstalk Isolation20dB typical20dB (min)
Current145mA [max]150mA [max]
Output VSWR2.0 : 12.5 : 1
Temperature Range-22 ~ +140°F / -40 ~ +60°C-22 ~ +140°F
Interesting. The stability is higher on this newer model. But Phase noise is way down and the gain is much flatter. Should be interesting to test.
 
mr3p

mr3p

Thread Starter
SatelliteGuys Pro
Pub Member / Supporter
Jan 1, 2010
1,229
202
West
Unless I am mistaken, you want stability to be a lower number. The stability of the C2-PLL is much better than the C238
 
  • Like
Reactions: johnnynobody
mr3p

mr3p

Thread Starter
SatelliteGuys Pro
Pub Member / Supporter
Jan 1, 2010
1,229
202
West
Since I'm already talking to myself... To the best of my knowledge, I'm not currently being affected by 5g although I'm sure its coming. Just wondering if there would be any value in a new "5g" scalar design to shield the LNB from signal outside of that reflected from the dish. Titanium any thoughts?
 
Titanium

Titanium

AI6US
Lifetime Supporter
May 23, 2013
7,375
8,509
Meadow Vista, Northern California
Sorry, have been quite busy over the weekend.

Yes, we have the new C138 and C238 LNBFs inbound. Have not set the retail price as the shipment is still moving through customs, dock warehousing and ground logistics. The cost is increasing by the day during these processing delays...

These models are very effective in attenuating outside the narrower band pass frequency range and preventing front-end conversion overload. After the next c-band auction and reallocation, we will manufacture the C140 and C240 models with the reduced frequency band pass range of 4.0 to 4.2GHz.

Most satellite hobbyists rarely chase the narrow SCPC radio and data carriers. The majority of hobbyists focus on the wider video SCPC and MCPC. With these wider signals, the stability figure is less critical and my focus was on the ability to mitigate interference for the uses of our primary market.

Why should one upgrade from the C1-PLL or C2-PLL to the C138 or C238 LNBFs? No need to install a filtered LNBF with narrower BPF (Band Pass Filter) if you do not have RF interference. As usual, you won't find me trying to sell hobbyists something that they don't need... :biggrin

You may find one scalar design to be better suited to your specific reflector's characteristics. With that said, I see little benefit to the new universal "5G" scalars being promoted for rejecting 5G interference. My observation is that these "5G" scalars have similar results to fabricating a side wing or deeper cone to your existing scalar to minimize off-axis entry of terrestrial signals. If the current scalar is properly installed, the reflector illumination area and side lobe attenuation are already optimized. Those experiencing SNR gains likely are benefiting from a design that is better matched to their reflector or better positioned scalar. One cannot argue if a change results in more reliable reception.

You need to be aware of the signal path that interference is reaching the feed. If off-axis terrestrial signals are directly entering the feed, it would be better to shield the entire reflector and feed from unwanted signals with reflector rim mounted hardware, a shielding "RF" fence or a behind a structure. A motorized dish creates a moving target for rejecting terrestrial interference...
 
FTA4PA

FTA4PA

Satellite Guys Family
Lifetime Supporter
Nov 13, 2013
5,577
3,492
Central Pennsylvania
Sorry, have been quite busy over the weekend.

Yes, we have the new C138 and C238 LNBFs inbound. Have not set the retail price as the shipment is still moving through customs, dock warehousing and ground logistics. The cost is increasing by the day during these processing delays...

These models are very effective in attenuating outside the narrower band pass frequency range and preventing front-end conversion overload. After the next c-band auction and reallocation, we will manufacture the C140 and C240 models with the reduced frequency band pass range of 4.0 to 4.2GHz.

Most satellite hobbyists rarely chase the narrow SCPC radio and data carriers. The majority of hobbyists focus on the wider video SCPC and MCPC. With these wider signals, the stability figure is less critical and my focus was on the ability to mitigate interference for the uses of our primary market.

Why should one upgrade from the C1-PLL or C2-PLL to the C138 or C238 LNBFs? No need to install a filtered LNBF with narrower BPF (Band Pass Filter) if you do not have RF interference.

You may find one scalar design to be better suited to your specific reflector's characteristics. With that said, I see little benefit to the new universal "5G" scalars being promoted for rejecting 5G interference. My observation is that these "5G" scalars have similar results to fabricating a side wing or deeper cone to your existing scalar to minimize off-axis entry of terrestrial signals. If the current scalar is properly installed, the reflector illumination area and side lobe attenuation are already optimized. Those experiencing SNR gains likely are benefiting from a design that is better matched to their reflector or better positioned scalar. One cannot argue if a change results in more reliable eception.

You need to be aware of the signal path that interference is reaching the feed. If off-axis terrestrial signals are directly entering the feed, it would be better to shield the entire reflector and feed from unwanted signals with reflector rim mounted hardware, a shielding "RF" fence or a behind a structure. A motorized dish creates a moving target for rejecting terrestrial interference...
I'm down to my last C2-PLL so was just wondering. Thanks for the info. I saw a story the other day (can't recall where) about the backlog for unloading ships out in California. Hope you have good luck on getting them through and thanks for supporting our hobby! :)
 
M

moonbase

SatelliteGuys Family
Pub Member / Supporter
Jul 16, 2015
36
16
UK
That C238 does not look like a PLL to me with the LO stability of 1MHz. It is 20 times the value of the C2-PLL.
 
M

moonbase

SatelliteGuys Family
Pub Member / Supporter
Jul 16, 2015
36
16
UK
Unless I am mistaken, you want stability to be a lower number. The stability of the C2-PLL is much better than the C238


Yes agreed, C2-PLL has way better LO stability.
 
C

c-spand

SatelliteGuys Pro
Feb 25, 2019
1,234
723
1
i am getting all signals like normal on all sats except 121. i use to get 410 no problem now cannot lock this at all. i do get 2 data v signals but nada on any video. Not sure but maybe this is the 5 g interference.
 
Titanium

Titanium

AI6US
Lifetime Supporter
May 23, 2013
7,375
8,509
Meadow Vista, Northern California
i am getting all signals like normal on all sats except 121. i use to get 410 no problem now cannot lock this at all. i do get 2 data v signals but nada on any video. Not sure but maybe this is the 5 g interference.
As 5G is not yet using the C-band reallocated frequencies in North America, I would look for other reception issues.

No, the C138 and C238 are not PLL based. As mentioned in my previous post, narrow SCPC usage is likely to be reduced with the shrinking band and we are focusing on filtered LNBF designs which provide the best interference mitigation. In our testing,, the 3800 - 4000 MHz band pass filtering works best on the non-PLL chipset builds.

The stability has been tested to be well below 1MHz (+/- 3MHz is typical in rhe market for DRO LNBFs), but we chose to spec. the max stability drift for 1MHz for premanufacturing chip sorting.
 
Last edited:
C

c-spand

SatelliteGuys Pro
Feb 25, 2019
1,234
723
1
As 5G is not yet using the C-band reallocated frequencies in North America, I would look for other reception issues.

No, the C138 and C238 are not PLL based. As mentioned in my previous post, narrow SCPC usage is likely to be reduced with the shrinking band and we are focusing on filtered LNBF designs which provide the best interference mitigation. In our testing,, the 3800 - 4000 MHz band pass filtering works best on the non-PLL chipset builds.

The stability has been tested to be well below 1MHz (+/- 3MHz is typical in rhe market for DRO LNBFs), but we chose to spec. the max stability drift for 1MHz for premanufacturing chip sorting.
Thank you Ti.
 
E

espaun206

SatelliteGuys Family
Oct 4, 2017
76
12
Guatemala
Hi Titanium they will continue to manufacture C1-PLL Filter ???

I do not intend to buy these new ones, they are very expensive

In addition, it seems that the C1 PLL have better stability.
 
  • Like
Reactions: moonbase
M

moonbase

SatelliteGuys Family
Pub Member / Supporter
Jul 16, 2015
36
16
UK
Where did Brian say it was a Pll lnbf?


He did not say it was PLL.

However, "mr3p" asked about the PLL status in the first post of this topic, my reply was relevant to his question at the time of posting.
 
Titanium

Titanium

AI6US
Lifetime Supporter
May 23, 2013
7,375
8,509
Meadow Vista, Northern California
Hi Titanium they will continue to manufacture C1-PLL Filter ???

I do not intend to buy these new ones, they are very expensive

In addition, it seems that the C1 PLL have better stability.
We have discontinued manufacturing the C1-PLL as they will no longer be effective in attenuating adjacent frequency interference <3800MHz. This frequency change will create the majority of the market demand during the next few years. Sorry that we have lost your future business, but the cost to manufacture and import has dramatically increased in the past two years.

If the C1-PLL were to be produced today, it would retail at a price that is similar to the C138. Component and logistics cost along with the 25% tariff are affecting almost every electronic item. We had kept the C1-PLL and C2-PLL retail prices set until the stock was depleted, as they were based on our cost at the time of manufacturing.

Do you chase narrow SCPC radio channels? If so, you will benefit from the PLL stability. For most hobbyists, we listen to Radio and watch TV muxes (MCPC). With any MCPC or SCPC video service, the C138 and C238 <1MHz will provide a solid lock and the ± 50Khz stability is not needed.
 
Last edited:
Captain Midnight

Captain Midnight

SatelliteGuys Pro
Sep 16, 2019
476
311
Greers Ferry, Arkansas
We have discontinued manufacturing the C1-PLL as they will no longer be effective in attenuating adjacent frequency interference <3800MHz. This frequency change will create the majority of the market demand during the next few years. Sorry that we have lost your future business, but the cost to manufacture and import has dramatically increased in the past two years.

If the C1-PLL were to be produced today, it would retail at a price that is similar to the C138. Component and logistics cost along with the 25% tariff are affecting almost every electronic item. We had kept the C1-PLL and C2-PLL retail prices set until the stock was depleted, as they were based on our cost at the time of manufacturing.

Do you chase narrow SCPC radio channels? If so, you will benefit from the PLL stability. For most hobbyists, we listen to Radio and watch TV muxes (MCPC). With any MCPC or SCPC video service, the C138 and C238 <1MHz will provide a solid lock and the ± 50Khz stability is not needed.
People worry about stability I think because of the higher FECs and schemes like 16APSK and up. For now, I haven't had issues, but when the time comes, I'll pay the piper and upgrade with a quality Ti LNBF. People fuss over cost, but they should price out an orthomode feedhorn with 2 new narrow band LNBs...
 
  • Like
Reactions: Titanium

Users Who Are Viewing This Thread (Total: 0, Members: 0, Guests: 0)

Top