Logo

Satellite Internet Forum.
Please note that this forum is now READ ONLY and closed for login and changes
The new forum is here Space and Satellite Communications forum

Welcome, Guest.
Welcome to this satellite broadband discussion forum.  Wherever you are and whatever your problem we are here to help each other. Connecting to the internet via satellite is not always easy but is critically important to those in remote places or with poor terrestrial infrastructure.  Both service providers and customers are encouraged to contribute.  Read the Forum rules.
      Satellite internet forum          

Dish heaters/Feed Horn Heaters

(Read 7647 times)
Uscg_Retired
Ex Member


Nov 28th, 2006 at 9:17pm  
I have a .98 round dish with Hughes /Direcway in a snow environment. The dish has to be  cleaned off every so often as the intenet link of course is gone. Climbing up the tower isn't really healthy during winter. Any body have a lead on a dish heater. The dish is plastic so I expect overtime that some cracking may occur, however, it is actually easier to replace the dish once in awhile to maintain internet access 24/7
Back to top
 
 
IP Logged
 
USN - Retired
Ex Member


Reply #1 - Nov 29th, 2006 at 12:39am  
The dish isn't actually plastic, it's basically a limestone and fiberglass composite that is molded over an electrostatic reflecting grid. Even so, I do not recommend dish heaters (or covers) of any kind on consumer grade hardware; too much potential for EMI, not to mention a potential safety hazard out in the wet/cold.

Clean the dish well spring and fall, rubbing in a coat or two of Rain-X protectant. The rub-on kind, not the windshield washer stuff. If the dish is clean and slippery, the wet snow/ice will fall off before it accumulates. Then buy yourself one of those kids Super-Soaker guns for winter. That's where you put the windshield washer stuff, to rinse off the stubborn stuff that doesn't want to slide.

//greg//
Back to top
 
 
IP Logged
 
USCG_Retired
Ex Member


Reply #2 - Nov 29th, 2006 at 5:03pm  
I wish it was that easy. There are about 30 of these that I need to addess as they are used in commercial area. Some are on poles way out of reach.
Back to top
 
 
IP Logged
 
USN - Retired
Ex Member


Reply #3 - Nov 29th, 2006 at 5:55pm  
In that case dish heaters are the tool of last resort. Forget covers, they introduce signal attenuation by themselves, not to mention any additional attenuation from clinging slush/ice.

If all 30 of your dishes are optimized for ACP (max) AND have a reasonable RSL margin AND have better than minimum electrical and signal grounds -  heaters can be used. But understand, the tradeoff is almost certainly going to be EMI. If these conditions are not met, EMI can kill a connection right outa the box. On marginally grounded connections, modem lockups can be expected. On optimized connections, expect a slowdown on your uplink speeds, and increased packet loss on your receive.

//greg//
Back to top
 
 
IP Logged
 
bajadudes
Ex Member


Reply #4 - Nov 29th, 2006 at 6:08pm  
Prodelin makes a specific dish heater for your .98 dish. 

You probably have a prodelin Product ID 1984-990 .98M RT KU .8 F/D                              
Product ID 0800-3271 .98 Reflector                                          
Product ID 0800-3282 Az/El PSNR .98F/D Fine

We sell a lot of these heaters to AK and Canada and as far as I know there has been no issue on a correctly pointed and peaked dish.

The heaters have been tested by Prodelin to work with their dishes and are UL listed.

contact me off list for pricing.

regards
Max                                    
Back to top
 
 
IP Logged
 
bajadudes
Ex Member


Reply #5 - Nov 29th, 2006 at 9:01pm  
Just to clarify these retro-fit units consist of a heavy duty goretex cover with a send and return duct that go to a heater box which mounts on the pole. 

There is a 120VAC input that converts down to 48VDC for the heating element.  The feed horn heater is a 24VDC waterproof electric blanket type heater.  both are UL and CUL listed.

If the de-ice kit is ordered from the factory with the dish then a preinstalled plenum is mounted on the back of the dish and connected to the heater box.

Like I said I have never heard of issues or complaints from customers.

I am sure that there is a marginal trade off in attenuation for the cover but it's a lot better than the attenuation and scatter you will get with a pile of snow and Ice on the dish.

As far as EMI I don't see how a hot air system can introduce that?
Back to top
 
 
IP Logged
 
USN - Retired
Ex Member


Reply #6 - Nov 30th, 2006 at 4:58am  
Quote:
As far as EMI I don't see how a hot air system can introduce that?

Any time there's AC present, you've got to worry about EMI. If/when 60Hz invades coax, strange things happen to the electronics on one or both ends.

But I don't see this hot air device on the Prodelin website.  Your description makes this cover thing sounds clumsy, meaning I'd worry about it in the wind too. You sure it's not some aftermarket thing that just coincidentally "fits" the 98cm Prodelin?

I'd have far less concerns about a heating system if it is actually made (or made available) by the dish manufacturer themselves.

//greg//
Back to top
« Last Edit: Nov 16th, 2014 at 8:39pm by Admin1 »  
 
IP Logged