How to convert from 4DTV to FTA box out on the dish?

Radioguy41

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Aug 7, 2008
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Lehighton, PA
The 4DTV has 2 LNB's (C & Ku) and 2 input cables, 1 for C-band and 1 for Ku and the polarity/voltage is controlled by the 4DTV thru a separate cable. I am replacing that box with a V-Box and straight FTA receiver. That means a single input cable and the polarity is controlled via voltage switching thru that cable. OK, I'm open to ideas as to how to get the dual LNB out on the dish to work with the new setup inside the house. Is there a magic switch I could mount somewhere or do I need to replace the whole shebang on the dish with an FTA LNB or? I'm sure there are folks on here that have already built this wheel so how did you handle it?
 
The simplest way would be to just replace the 4dtv with the v-box. A diseqc switch can choose Ku or C-band cables. Might have issues on vertical polarity though so a powered switch or power inserter can be installed on each cable so the LNBs get 18v. Think there is a circuit you can build to control the polarity servo somewhere (other members might have this bookmarked) using high/low voltage signal from the receiver...

Second: If you can find an ASC1 it can do the skew on your Chaparral feed horn and a diseqc switch can control which input (C or Ku) to select for each satellite. You already have a V-box, don't think they do skew though so this unlikely to be an option, would actually be the simplest though...

Third option would be a bullseye type feed horn with four LNBs and a milti-switch to power the LNBs, that gives you C and Ku on the big dishwithout the need for the polarity servo.

Fourth: replace the feed horn and LNBs with an LNBF. Brian sells some good ones. Go with C-band only on the big dish and add a motorized Ku dish for Ku. The Ku dish would use USALS/Diseqc control so the cable from the receiver goes to the Ku motor, then split off using diseqc 1.0 or 1.1 switch to Ku LNBF and C-band LNBF.

I did this many years ago, never did the bullseye option was too pricy for me at the time... Currently using a spider's web of cabling, switches, and many dishes. I should make up a schematic some time... :)
 
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The simplest way would be to just replace the 4dtv with the v-box. A diseqc switch can choose Ku or C-band cables. Might have issues on vertical polarity though so a powered switch or power inserter can be installed on each cable so the LNBs get 18v. Think there is a circuit you can build to control the polarity servo somewhere (other members might have this bookmarked) using high/low voltage signal from the receiver...
I believe this is what Cham is referring to - a mod to add polarity control to the VBox type movers. :)



 
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The simplest way would be to just replace the 4dtv with the v-box. A diseqc switch can choose Ku or C-band cables. Might have issues on vertical polarity though so a powered switch or power inserter can be installed on each cable so the LNBs get 18v. Think there is a circuit you can build to control the polarity servo somewhere (other members might have this bookmarked) using high/low voltage signal from the receiver...
The 4DTV has separate LNB's, each with it's own cable to the house and each to a separate input on the 4DTV box. The V-Box only has a single input.

Second: If you can find an ASC1 it can do the skew on your Chaparral feed horn and a diseqc switch can control which input (C or Ku) to select for each satellite. You already have a V-box, don't think they do skew though so this unlikely to be an option, would actually be the simplest though...
Already have the V-Box in place.
Third option would be a bullseye type feed horn with four LNBs and a milti-switch to power the LNBs, that gives you C and Ku on the big dishwithout the need for the polarity servo.

Fourth: replace the feed horn and LNBs with an LNBF. Brian sells some good ones. Go with C-band only on the big dish and add a motorized Ku dish for Ku. The Ku dish would use USALS/Diseqc control so the cable from the receiver goes to the Ku motor, then split off using diseqc 1.0 or 1.1 switch to Ku LNBF and C-band LNBF.
This is an option as I've had a separate Ku dish for years.

I did this many years ago, never did the bullseye option was too pricy for me at the time... Currently using a spider's web of cabling, switches, and many dishes. I should make up a schematic some time... :)
Ah, I was typing while FTA4PA was posting. Thanks, some interesting reading.
 
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Ideas are there for the asking. I took my Corotor off a few years ago and put one of Brian's C-Band LNBF's on.
I have a box of Corotor's and a Harvard ortho feed. I thought I wanted to stay with one or the other because I had a 4DTV setup also. I ran C-Band only until about a year ago.
ASC1, C2W Wideband, and an Osmio 4K.
A bit of learning and tweaking and refurbing the dish with pillow block bearings, extending the actuator mount. Bla-Bla.
Got interested in Ku adding to the dish. Not really much I watch on that band. I got a Maverick Ku LNBF.
Dont worry. It looks off kilter (Ku LNB) but with the dish at its highest arc it is parallel to the ground right beside the other feed.
At first the signal sucked. I hand held it to grab a signal before working out the mechanics of mounting the thing.
I was aimed dead at a C band sat that carried Ku also. Peaked the position for highest dB. Ku signal sucked. Until I realized that the center of the button hook casting was obscuring my Ku signal. Bumped the dish West a little. Hand held the LNB and got a signal. Made a bracket, bolted it to the scalar. Stuck the Ku on and bent and tweaked for the highest signal. Skew matched my C-Band spot on. V & H tp's had the same dB.
Now. Time to get the electronics setup.
It would work on it's own cable plugged into the receiver. With a 22 kHz switch, no joy. No way, no how. I think it was a glitch in my image on the mio. Anyway. I had a 4 port DiSEqC lying around. I tried that and figured out the settings in my receiver to make it work (never used one before....nor a 22 kHz switch). Bang. Success!
After a little brain work I ciphered that the Maverick was shooting 5 degrees west of what a aimed dead-nuts C-Band sat was. A little bending of the bracket put that spot on. The switch is tucked in behind the receiver inside out of the weather.
I had to get an APC backup. Here in the sticks the pixies go out "frequently".
When they do for a moment, the ASC1 powered back up and sent the dish wherever it wanted to go.
Messing up my "counts" reference. That was a PITA. It was driving the dish to it's electrical limit and not counting. APC that baby!
Man. What a bummer! There isn't really crap on Ku that I care to watch. I can get enough "shortwave Jesus" on my Icom rig. Haha!
All in all it wasn't really that hard to do. And I have new electronics and don't have to worry about about the probe motor hunting in the dead of winter. And having to suit up to go fix it. Ku reception on strong sats simply blasts in at close to 16 dB or more.
 

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The 4DTV has 2 LNB's (C & Ku) and 2 input cables, 1 for C-band and 1 for Ku and the polarity/voltage is controlled by the 4DTV thru a separate cable. I am replacing that box with a V-Box and straight FTA receiver. That means a single input cable and the polarity is controlled via voltage switching thru that cable. OK, I'm open to ideas as to how to get the dual LNB out on the dish to work with the new setup inside the house. Is there a magic switch I could mount somewhere or do I need to replace the whole shebang on the dish with an FTA LNB or? I'm sure there are folks on here that have already built this wheel so how did you handle it?
A 1x2 diseqc switch? The receiver can be configured to select the LNB by which switch port it's using.
 
A 1x2 diseqc switch? The receiver can be configured to select the LNB by which switch port it's using.
He still would need polarity control some how. I am with arlo in keep it simple. Get a titanium LNBF and a separate Ku dish and use a 4X8 switch, preferably powered. Even with a polarity controller, your Ku will suffer on the Cband dish.
 
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I think I still have a Pansat DP4 here that I am willing to part with. You would need 2 Cband LNB's and 2 Ku LNB's to use it and a powered multi switch. The WNC are cheap on Ebay.
 
He still would need polarity control some how. I am with arlo in keep it simple. Get a titanium LNBF and a separate Ku dish and use a 4X8 switch, preferably powered. Even with a polarity controller, your Ku will suffer on the Cband dish.
Yeah I forgot that he had standard LNBs and not LNBFs.
 
OK, I ordered a Titanium C1W-PLL LNBF from Amazon, should be here tomorrow. I currently have a Chaparral feedhorn setup. Will the LNBF fit into the existing scalar or must I use the one included?
 
Will the LNBF fit into the existing scalar or must I use the one included
It'll likely fit, however, you might have to add some shims as the LNBF will likely be smaller circumference than the old-school lnb feedhorn. Without some sort of shims all around the barrel, it'll likely be a hair off-center, or floppy and lean instead of being straight.
 
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All components have arrived. The V-Box is installed and connected. I went out to the dish, ripped off the corotor assembly and mounted the C1W-PLL. By the way it fits right into the existing scalar. Also the blue cover no longer has a hole in it for the bees to get in. With bad weather rolling in I did a quick eye-it-up installation and successfully scanned in SES-3. The next decent weather break I'll tweak it. As of now I'm very pleased.

Out with the (28 years) old original setup:
Chaparral-1.jpg


In with the new (before finishing up):
New LNBF-1.jpg
 
With the arrival of the Amiko from Brian today I think I'm going to try some experimenting. When I go out to tweak the C-band LNBF I think I'll tie a Ku LNBF off to the side on an angle using the left half of the dish as an offset and see if I can pull in any Ku signals from an adjacent bird using the Amiko. Might be fun. :)

By the way, when I removed the feedhorn cover yesterday it was completely full of dried hornet nest. That's the 3rd or 4th time I found it full and no matter what I do they manage to find a way back in. :mad:
 
Keep in mind that cover needs to breathe. Hot Sun expanding the air during the day, cold air pulling it back in at night. Can't make it airtight, the expanded air has to get out somewhere. I've seen it push the caulk right out. This one has a vent in it and I think that may be how they're getting thru. I think I'm going to try super gluing a piece of screening over top of the vent.