PCS Electronics PCS Electronics - home page PCS Electronics  
RegisterSearchFAQAM & FM Radio transmitters shop UsergroupsLog in
How to measure an antenna's max RF capacity?

 
Reply to topic    PCS-Electronics Forum Index » Antennas View previous topic
View next topic
How to measure an antenna's max RF capacity?
Author Message
Radio Liberdade
New registered user
New registered user


Joined: 15 Mar 2019
Posts: 1

Post How to measure an antenna's max RF capacity? Reply with quote
Is there any way to measure an antenna's maximum RF capacity? We are having an antenna system without any written documentation installed on site and it is working more or less fine with the small transmitter installed. (2 folded dipoles at 30m on a 100 w transmitter) We would like to test, how much a new 1.000 W Cybermax would increase our coverage, using the current antenna system. Is there any alternative to just slowly increasing the output power of the Cybermax until the reflected power increases too much?
We have an antenna analyzer (rigexpert AA-600) on site but so far we only used it check the SWR. Can we also use it to determine the max power load of the entire antenna system?
If not, what would be the highest acceptable reflected power reading for a constant operation without risking damage to the antennas, the combiner, the coax or the transmitter?
Mon Mar 18, 2019 4:50 am View user's profile Send private message
ABC FM
New registered user
New registered user


Joined: 24 Feb 2016
Posts: 2

Post Reply with quote
At the first place, high vswr will damage your transmitter, if there is no protection. Then, in extreme case, it will burn the coax. High vswr does not indicate antenna power handling, it indicate impendance missmatch. Max vswr is 2:1 or 10% of nominal power. Now about antenna. Nobody can tell you exact what can your antenna handle. If there is N connecton on antenna, it could be indication that can run at 500w. But it is just indication (who knows what kind balun material is inside, what kind of insulation..). if there is 7/16 connector on antenna, that could mean that rated power is more than 1kW. Same for divider. If it is metal tube with N connectors, perhaps can handle up to 500w. Coax divider usual can handle lower power. Interconnection between divider and antennas is also important. for high power minimum is rg213 or similar. As main coax rg213 can handle up to 700w
Tue Mar 19, 2019 9:56 pm View user's profile Send private message
pcs
Site master
Site master


Joined: 18 Jan 2002
Posts: 3099
Location: Radio Land

Post Reply with quote
One way to find out is to try... at some point it will fail, either arc over, form a short or open circuit.

Any of these conditions is also likely to damage the transmitter in the process.

So... if you have to ask it may be best to buy your antenna from a reputable source.

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Wed Mar 20, 2019 7:58 pm View user's profile Send private message Visit poster's website
Display posts from previous:    
Reply to topic    PCS-Electronics Forum Index » Antennas All times are GMT + 1 Hour
Page 1 of 1

 
Jump to: 
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 vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group