All times are UTC+02:00




Post new topic  Reply to topic  [ 20 posts ]  Go to page Previous 1 2
Author Message
PostPosted: Sat Oct 18, 2014 6:22 am 

Joined: Fri Oct 17, 2014 2:45 am
Posts: 8
ahh this is good alternative...i can try this option...Very thanks..


Top
   
PostPosted: Sat Oct 18, 2014 3:41 pm 

Joined: Mon Aug 25, 2014 3:22 pm
Posts: 282
But keep in mind any extra heliax will reduce power input to the antenna because of line loss. So you'll want to look up the specific cable you're using to carry the RF, figure out its line loss, and up your TPO precisely to compensate.


Top
   
PostPosted: Sat Oct 18, 2014 3:57 pm 

Joined: Fri Oct 17, 2014 2:45 am
Posts: 8
Of course !, talking to a local technician recommended I use the rg59, another technician recommended me utp cat6. you think?


Top
   
PostPosted: Sat Oct 18, 2014 7:04 pm 

Joined: Mon Feb 04, 2013 11:25 pm
Posts: 153
cat 6 should work, what about a fiber link?


Top
   
PostPosted: Sat Oct 18, 2014 7:24 pm 
User avatar

Joined: Tue Mar 17, 2009 2:56 pm
Posts: 4163
RG213 or CFD400

_________________
control point
control point2


Top
   
PostPosted: Sun Oct 19, 2014 4:25 am 

Joined: Fri Oct 17, 2014 2:45 am
Posts: 8
who think of using a balun utp like these?
http://www.amazon.com/gp/aw/d/B007XUU6E ... 15&simLd=1


Top
   
PostPosted: Sun Oct 19, 2014 3:43 pm 

Joined: Sun Feb 10, 2013 6:58 am
Posts: 152
Location: Sydney, Australia
From my perspective I still think your best choice is to move the exciter to the PC, use a long length of good heliax from the exciter to the power amp stages and adjust the exciter to compensate for the loss in the 50 metre run of heliax.

Though 50 metres of decent heliax is going to cost you hundreds of dollars.

Maybe a cheaper option is to run your program signal (+4 balanced) to the computer for 50 meters and then a very short cable from the computer to the MPX input of your exciter. Costs you 100 metres (50 Left, 50 Right) of decent co-ax about $150.


Top
   
PostPosted: Sun Oct 19, 2014 4:01 pm 

Joined: Fri Oct 17, 2014 2:45 am
Posts: 8
my problem is this: my driver can not be separated from the transmitter, and the computer is a 30, 35 meters. computer is used to air can not put it next to the transmitter. so my question is: can be balanced with balun and unbalance on the other end?


Top
   
PostPosted: Sun Oct 19, 2014 5:38 pm 

Joined: Sun Feb 10, 2013 6:58 am
Posts: 152
Location: Sydney, Australia
You could try the balun but I think you may find the stereo separation suffers. It is something you'd have to try to see what the results are. Maybe put a signal into one of them and look at the result on the other end.

At a guess I would say the transformers in those baluns are 75 ohms to 110 ohms (75:110). The CAT 6 would give you about 25ns delay skew for 30 to 35 metres and probably about 1 degree phase error at MPX frequency.

It's worth a try if you've got a pair of those baluns on hand.

C.


Top
   
PostPosted: Fri Oct 24, 2014 1:00 am 

Joined: Mon Feb 04, 2013 11:49 pm
Posts: 187
Using coax between the exciter and transmitter will only cause reduced power if the exciter is running at full power now. Most exciters operate at lower than maximum power....say a 50 watt exciter runs at 30 watts. If you lose 2 watts in the longer coax, turn the exciter power up by 2 watts to compensate. It's very unlikely for power loss to be a significant problem. Run this by your RF transmitter guy to confirm it first, then move the exciter to where the ST computer is located. End of story.


Top
   
Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 20 posts ]  Go to page Previous 1 2

All times are UTC+02:00


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Limited