comparing lnbf's

[gabshere]

man its hot outside .....
ok i will try to compare some lnbf's on my 7 1/2 ft mesh dish

the lnbf's are :
Cal Amp 35K pulse switched (about 16 years old) don't know if i can control the switching
Cal Amp 25K voltage controlled h/v switching ( about 13 years old)
DMSI ASC 421 13K
GeoSat pro C1 17K

The Weight:
ok first glance the older Cal Amps are sturdy built even have a led light on it
they out weigh the DMSI ASC421 4 to 1 ratio and the GeoSat pro C1 2 to 1

so guessing the weight
DSMI ASC 421 5 oz
GeoSat Pro C1 10 oz
Cal Amp 35K 15 oz
Cal Amp 25K 20 oz

The Construction :
the Cal Amps are solid , sturdy older lnbf's using a metal closer to chap corotors for construction. they have no skew marks and the scaler (fd) marks are very readable.

the DMSI ASC 421 is a lightweight material the scaler hole is a bit smaller than the others its close to 63 mm while the others are closer to 65mm. the skew marks are easy to see and read. the scaler markings are very clear and easy to read.

the GeoSat Pro C1 is a lightweight material a little bit heavier than the ASC421 it also has a heavier paint coating . the skew marks are a bit hard to see but are there . the scaler marks are also there but harder to see.

more to come

do you have a certain c band satellite you would like # from. let me know. as i'm waiting for it to cool off.

 

[gabshere]

first up was the ASC421 well it wouldn't fit the scaler it was too small and the i didn't have anything to shim it so it would be properly centered..... putting on the back burner until tomorrow ...

next up is the older cal amp 25k lnbf

ok that ones done next up is the Geosat pro C1

ok the baseline is:

....................BSC621..........Cal-Amp 25K..........GeoSat pro C1..........ASC421..........Cal-Amp 35K
AMC3 87W
3824H..........92S 90Q.........93-94S 87-88Q......94S 88Q...............96S 87Q........... not tested
4174H..........86S 87Q.........94S 87Q................93S 87Q................97S 93-94Q
3834H..........94S 94Q.........96S 94Q................96S 94Q.................97S 91-94Q
4036H..........87S 94Q..........94S 94Q...............97S 94Q.................97S 93-94Q
4178V..........87S 91Q..........94S 91Q................93S 91Q................97S 91-94Q
4049V..........92S 91Q..........95S 93-94Q...........94S 97Q................97S 94Q

G3 95W
3744V..........97S 97Q..........97S 97Q................97S 97Q................97S 97Q............not tested
3736V..........97S 94Q..........97S 91-92Q............97S 94Q...............97S 93-94Q
4040H..........96S 91Q..........97S 91Q.................97S 91Q...............97S 90-91Q
3728V..........97S 97Q..........97S 87Q................97S 94-97Q..........97S 94Q

G16 99W
3950H..........95S 94-97Q.....97S 94-97Q............97S 94-97Q.........97S 94-97Q
3880H..........97S 91Q..........97S 88-90Q............97S 90-91Q .........97S 91Q
4001H..........97S 97Q..........97S 97Q..................97S 97Q..............97S 97Q

AMC 1 103W
3840H..........97S 91-94Q.........97S 90-91Q........97S 91Q..............97S 91Q...........not tested
3984H..........88S 93-94Q......95S 90-92Q..........97S 94Q ..............97S 93-94Q
3740V...........97S 89-91Q......97S 87-88Q..........97S 90-91Q.........97S 90-91Q
4006H..........94-95S 93-94Q...97S 94Q..............97S 94Q..............97S 94Q

G10R 123W
3954V..........96S 92-94Q.....97S 91-93Q........97S 91-94Q............97S 91Q...........97S 90-91Q
4181H..........95S 94-96Q.....97S 87-90Q........97S 90-91Q............97S 88Q...........no signal

the cal amp 35k received several signals on g10r but i ran out of time to check all of them. some signals were both polarities H & V and this was the pulse switched lnbf which i didn't have connected up to switch.


these comparison were made with a coolsat 5000 and 7 1/2 ft mesh dish. they were to compare signals with each lnbf not to say which is a better lnbf but just to compare the signals. adjustment for each satellite wasn't made, adjustment and fine tuning was only made from g10 and all the arc from there fell into place. so your numbers might vary slightly. This did show that the Geosat pro C1 17K compared close in numbers to the BSC621 13K , but then again the older 25K cal amp clocked in with good numbers also.

 

[gabshere]

ok i got the asc421 to shim up and got some numbers .... now i don't want you to think these are numbers set in stone cause it would have probably been the better method to remove my scaler and place the proper sized scaler up and then check the numbers. but since this is for just a close up comparison and not which is the best type of thing . <<<---------- so this note is for those seeking the maximum performance........

 

[gabshere]

conclusion to the comparison is all these would work great for my stationary project.
the cal amps if you can find them will be used and cheap... these would prove to be the best per cost if shipping was worth it. the geosat pro c1 & the asc421 both did well for my quick setup and testing. both prove that they would work well in my configuration of c band systems.

hopefully my next test will compare my bsc621 to a geosat c / ku version ( will have to buy one)

 

[Mr Tony]

very nice

I have the 2 LNBF's you posted and an older 25K LNB and they all seem to work pretty good. The only issue I have is the DMSI one seizes up on the H side in cold (+10F or below) and won't work

 

[gabshere]

it seems to have real thin metal, have you thought of sealing up the coax end and placing the feedcover on , and using some of that plastic dip (some people use this stuff to dip their tools) to add an extra layer or two of material over the metal it see if it will act like an insulation during the cold. might save a lnb ( instead of trowing it away). i think the probes are ok but i suspect the other parts can't handle the extream cold.

 

[linuxman]

Nice comparison George!

I know it is a lot of work in the heat we are having.

I like the old Cal-Amp LNBs. They do a great job for the cost.

Fred

 

[iammike]

hopefully my next test will compare my bsc621 to a geosat c / ku version ( will have to buy one)

That's what I'm using these days. For what it's worth, it's performing pretty much equally to the C band performance and better than the KU from the Corotor II plus package I bought a couple years ago. Since the Corotor package runs $150 and the Geosat is $50 I've been pleased with the purchase. When you do your test, I'd be curious to see how the bsc compares to the geosat on KU.

Thanks for the numbers!

 

[49studebaker]

Any update on how the BSC compares to the GeoSat on KU band?

 

[gabshere]

never did buy one to compare

would still like to test them though

 

[Anole]

belated congrats

Quite educational on the Cal-Amp LNBf's. Certainly seem to hold up very well.
edit: similar item on Sumitsource for $40. Wouldn't have recognized 'em without reading this thread.

If you ever revisit this subject, maybe you could find just one or two weak transponders on one satellite, and see how they all compare with one or two strong transponders.
Perhaps with a Q down around 70..75, maybe?
I know that's a lot closer to the Coolsat's threshold of reception.

I also am curious about the CK-1 and the B1stacked, as they compare to your existing stock.
Maybe some day we can move enough hardware around to give that a chance.
Oh, and those MA/COM things Linuxman recently posted about, too. - :up
All very fascinating!

 

[ACRadio]

I've done a lot of experimenting with LNB's over the years. One important thing I learned is that the receiver quality often times don't tell the whole story, especially with c/n ratio. I have seen times (when I had a meter that would measure c/n...shouldn't have sold it) where the difference in quality was 2 or 3 numbers between 2 LNB's but the measured c/n remained nearly the same. Often times the receiver quality meter can't take into consideration the "noise" in an LNB. This aspect really rises to the top with a weak signal.

Here is an example I recently experienced. I had used California Amplifier Extended Professional II C band LNBs for years. They were 30 degree noise figure with 500 khz stability. This is on an 8 foot Channel Master fiberglass with a Bullseye II dual orthomode. A few months ago I started jonesing for a pair of Norsat 8115's (15 degree 100 khz stability) to replace the Cal Amps. One of my test frequencies was a notoriously weak network HD West distro. I used the Traxis 3500 to observe quality, and on the Cal Amp the quality was in the 39 to 43 range, which is an extremely weak signal. The picture showed a band or 2 of pixellation every 3 seconds or so...this is with a TT S2-3200 PCI card coming directly from the same multiswitch as the Traxis. After installing the Norsats I immediately noticed that the quality numbers had decreased on average about 2 markers across the board. I then checked the weak network distro and noticed the quality had dropped down into the 34-38 range, only bumping 40 maybe every couple of minutes. I remembered from mental notes that with the Cal Amp this is usually just enough for the Traxis to lock, and I would be greatly disappointed if I had sunk a wad of money that took months to come up with only to be worse off signal wise. But when I tested the signal it was found it to be flawless. The receiver quality numbers lied about the actual signal. It really didn't lie, but because of factors like stability, noise figure, and phase noise the receiver can't take those factors into consideration, and it becomes really impossible to compare LNB's by only using the quality meter in a receiver. Measured c/n ratio and actual comparing with a known weak signal are much more informative.

I am well pleased with the Norsats...no matter what the quality meter has to say...

 

[voomvoom]

I have a question for you, on that CalAmp Pulse Controlled LNBF, how/what do you hook the wire to? Does it go to the Pulse on an Analog receiver, if so, how is it grounded? How does it work? Can it be made to work with a DVB receiver?
I have one (mine is 25k), but I've never took time to play with it, as I can't comprehend as to what to do with that wire?

Nice comparison..!!

 

[gabshere]

ACRadio
yes this is a flaw in the comparison of the lnbs but it was the best i could do at the time , i would like to do a better comparison in the future and include these type of things. but i would have to figure out what would be needed maybe a spectrum analizer or something
cause i know that on the more stable lnb & lnbf they might give a lower signal & quality level on the dvb receiver but actually gain a better & more stable picture with the lower signal.

I have a question for you, on that CalAmp Pulse Controlled LNBF, how/what do you hook the wire to? Does it go to the Pulse on an Analog receiver, if so, how is it grounded?

i was worried about this also but when i hooked it up ( without connecting the one white wire) the dvb receiver only picked up one polarity so it would need the pulse wire hooked up ( on analog receiver ) to change the polarity or be used as a V polarity only lnbf

 

[Anole]

Most of us don't have professional test equipment, so any other way of comparison is still helpful.
I asked about testing weaker signals, in hopes it might show more difference than strong one.
Of course, with a large and well-aligned dish, maybe strong signals are the norm. -

The Coolsats are a bit odd, in that (as reported) it takes a signal quality in the low 60's to be visible at all.
Other receivers may give flawless reception while claiming quality in the 20's or 30's for the same transponder.
Just means everyone's meters are not calibrated equally.

Another factor I forgot to mention is the FEC of the received signal.
Whitesprings with their FEC of 1/2 can be received clearly with an even lower Q-level than most anything on the air!
So, they wouldn't be a prime candidate for using as a test signal. -

 

[gabshere]

especially with c/n ratio. I have seen times (when I had a meter that would measure c/n...shouldn't have sold it)

what type of equipment was this ? Spectrum Analyzer i would like to do more indepth reports on lnb's but don't have the equipment ..


i would also love to get a c-band pll lnb and test it

i did some other test last year or the year before reporting that several low end lnbf compared close to their high end counterparts. but this testing was done the same way and didn't take into account the stability of the lnbf so the high end lnbf could very well have been close on the comparison but probably locked and held at lower signals and held longer before pixalation ( i just didn't check these). i will have to go back and provide more through look at them

c/n ratio

i heard this before and i know its read in dB

 

[ACRadio]

what type of equipment was this ? Spectrum Analyzer i would like to do more indepth reports on lnb's but don't have the equipment ..


i would also love to get a c-band pll lnb and test it

i did some other test last year or the year before reporting that several low end lnbf compared close to their high end counterparts. but this testing was done the same way and didn't take into account the stability of the lnbf so the high end lnbf could very well have been close on the comparison but probably locked and held at lower signals and held longer before pixalation ( i just didn't check these). i will have to go back and provide more through look at them

i heard this before and i know its read in dB

Carrier to noise ratio...it was measured using an SF-3000 satellite meter which measures c/n. It's not calibrated to any standard like a spectrum analyzer so you can't use the results between devices but it can be used for relative measurements.

I shouldn't have sold the SF-3000...I dunno what got into me other than I was purposed to get a Trimax. I did some soul searching and decided that I didn't need to sink that kind of money into a meter so now I am without....

 

[1captain]

I have a question for you, on that CalAmp Pulse Controlled LNBF, how/what do you hook the wire to? Does it go to the Pulse on an Analog receiver, if so, how is it grounded? How does it work? Can it be made to work with a DVB receiver?
I have one (mine is 25k), but I've never took time to play with it, as I can't comprehend as to what to do with that wire?

Nice comparison..!!

The white wire goes to the skew or pulse on the back of any c-band receiver the same place where the white wire would go with the 3 servo control wires, then just have you're polaritys set like you would normaly -45 an +45.

yes will work with a DVB receiver but in needs to have the servo controls in it, I have 1 working with a Pansat 2500.