Just Sharing This AV-Comm Polariser + Zinwell lnbf

[drhans]

I quite like the "AV Comm" logo on it, actually.

The combo continues to impress. Blind scanned 40W with TBS5925 - 63 transponders locked with 283 services, with signal levels between 0.5db and 3db(!) higher than my last scan ...and this is on a gray, damp morning.

The polarizer is amazing, no doubt about that - but did you try to scan 40W immediately again without av-comm to compare? What I often notice at 40W and 43W is that the signal changes a lot, even by 2 dB or more, not really depending on the time of the day, but it simply seems that the broadcasters change the tx power from time to time.

 

[Captain Jack]

It's a good point and no, I haven't. But I've checked a few previous scans with a normal plate and all are down on signal...

 

[nelson_b]

Hi - folks
Hope to get my AV-COMM back from the engineering shop later today ... in the meantime though the Zinwell that i ordered from the USA some time ago finally arrived the other day...
so for now i,v installed it as - linear l.n.b. replacing the 6 degree off centre ESX241 on my 1.8 c.m. setup ...
most linear signals are up by between 0.5 db and 1.0 db ... so i,m well pleased with the Zinwell

 

[otokoc]

Dr.hans ı am 40mm cutıng my esx241 and good work now.

GT-I9300 cihazımdan Tapatalk kullanılarak gönderildi

 

[drhans]

Dr.hans ı am 40mm cutıng my esx241 and good work now.

thanks for the reply - but could you please share little bit more details with us:

1) did you measure difference between cutting 40mm and let's say 20 or 30mm only? when I cut my Titanium, Golden Interstar and some chinese gospell lnbf, I couldn't really see any difference in signal when cutting the whole feed vs. not cutting anything

2) you presented a chart of how the LNBFs perform from best to worst - could you add how much difference you saw? less than a dB, more than a dB...?

3) how did you attach the ESX to the polarizer?

I think everyone in this thread will aprreciate your input as you've clearly tried the most LNBFs with the polarizer. From my side, I can just say that from those I've tried so far, the best was no doubt Zinwell, followed closely by Golden Interstar and in the last place Titanium. I will probably get to trying ESX today.

 

[John]

thanks for the reply - but could you please share little bit more details with us:

1) did you measure difference between cutting 40mm and let's say 20 or 30mm only? when I cut my Titanium, Golden Interstar and some chinese gospell lnbf, I couldn't really see any difference in signal when cutting the whole feed vs. not cutting anything

2) you presented a chart of how the LNBFs perform from best to worst - could you add how much difference you saw? less than a dB, more than a dB...?

3) how did you attach the ESX to the polarizer?

I think everyone in this thread will aprreciate your input as you've clearly tried the most LNBFs with the polarizer. From my side, I can just say that from those I've tried so far, the best was no doubt Zinwell, followed closely by Golden Interstar and in the last place Titanium. I will probably get to trying ESX today.

Agree @drhans, the information gathered by @otokoc would be most welcome.

 

[aceb]

Coming into this thread a bit late really but as I've got a family friend coming back to Blighty from Sydney next week please hurry up and complete all tests comparing them to the Titanium and the ESX241 LOL

 

[moonbase]

Coming into this thread a bit late really but as I've got a family friend coming back to Blighty from Sydney next week please hurry up and complete all tests comparing them to the Titanium and the ESX241 LOL

aceb,

Is your friend bringing AV-COMM polarisers?


Rgds

 

[aceb]

If the improvement over the usual LNBs and plates is worthwhile I may ask her to do just that MB, she's only here for a week or so at her sisters wedding so not sure how much stuff she's bringing with her but am hoping there's room for an lnb and polariser.

 

[Captain Jack]

Definitely worth it, Paul.

 

[Channel Hopper]

I did matey, i forgot about those. Never did get around to implementing it.
Interesting bit of kit, especially if you like things to be PC based .... thinking about you @MB.

Most PC based stuff has an off switch.

 

[aceb]

Definitely worth it, Paul.

Slight change of plan, mum is going out to Sydney for six weeks at the start of January so will have loads of luggage. I asked her if she'd mind bringing one home, not only did she say that was OK she also said she'd buy it for my Xmas present, mums eh?

 

[drhans]

I've tried ESX242 with the polarizer. I did cut 4 cm off the feed. The good thing was that the lnb then fitted into the polarizer just fine since the diameter decreases the shorter the feed gets. But I think 4cm is too much as I've ended up positioning the LNB in a way where cutting just 2cm would be enough. So I suggest cutting only as much as necessary to insert the ESX into the polarizer and only if you notice the signal improving while pushing the lnb further into the polarizer, then start cutting some more...

My results are not representative since the LNB is placed 6-7 degrees off center, but I'd say it was worth it. I tested 40W again and I saw improvements on most transponders, in some cases by huge numbers (3980L jumping from 7.7 to 8.5 dB, 4009R up from 7.5 to 8.5 dB ). However, I never managed to find a spot where ALL transponders would be optimized. Getting a perfect signal on 3723L meant losing 3764R completely (to unlockable 9.1dB )! In the end this means one thing - everyone should try using ESX instead of Zinwell. Individual results will vary but maybe ESX will help you in getting transponders which were just below lock with Zinwell - even though other ones might be lost.

I've also tried rotating the polarizer and the LNB in it. The best result I've got was unfortunately the one where the polarities were "switched" (R=H, L=V) but that's not a big deal. This just shows that optimizing the reception with the polarizer is something that will take many many (enjoyble) hours of hard work!

Anyone thinking about getting the polarizer, you should still get it with Zinwell LNBF and scalar ring because you NEED the polarizer to be machined and you'll need a fitting ring. The first polarizer I've ordered was without the lnb and it was not machined which means it didn't fit any scalar ring and no LNB or OMT could be attached without hard work ...not worth saving some $80 on LNB and machining.

 

[John]

Absolutely agree with your findings @drhans .....
I did some similar tests a while back on a TiT lnbf and the AV-Comm polariser barrel and it really can be optomised to obtain a bit more performance with care.

 

[aceb]

Can some explain something about the AVcomm website, I was looking through the shop and see they sell a complete C band feed kit for $600 yet the three component pieces come in around $400. Is this 200 difference machining costs, seems a bit steep to pay to make their own products fit each other or have I missed something?
C Band High Performance Circular Feedhorn | Av-Comm

 

[John]

Can some explain something about the AVcomm website, I was looking through the shop and see they sell a complete C band feed kit for $600 yet the three component pieces come in around $400. Is this 200 difference machining costs, seems a bit steep to pay to make their own products fit each other or have I missed something?
C Band High Performance Circular Feedhorn | Av-Comm

... The short answer is no. Drop them an email, Garry the gaffer is a helpful guy.
Below is the breakdown on our recent barrel/Zinwell bulk buy. Shows just one cost for machining 5 barrels though.

 

[moonbase]

scopus,

Would you please be able to tell me if the clamp that holds the AV-COMM barrel to the LNB rotator is a home fabricated clamp or are they available over the counter. It is the clamp on the hexagonal nut with the threaded rod holding it in place on the LNB rotator (2nd picture in post 81 of this topic)

Thx

 

[Captain Jack]

Fabricated by Trust1 - came with the rotator.

 

[moonbase]

Fabricated by Trust1 - came with the rotator.

CJ,

Ah, thx for the info. I need a couple of those to mount an AV-COMM and another feed.

Rgds

 

[scopus]

scopus,

Would you please be able to tell me if the clamp that holds the AV-COMM barrel to the LNB rotator is a home fabricated clamp or are they available over the counter. It is the clamp on the hexagonal nut with the threaded rod holding it in place on the LNB rotator (2nd picture in post 81 of this topic)

Thx

They are pipe clamps, they are available over here in inox. I got some spare from BES plumbing supplies in Birmingham. And yes, studding attaches it to the revolver wheel.