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Gain Master

listner132

Member
Apr 23, 2014
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Hi guys just wanting to know if anyone has tried to make there own version of the Gain Master Antenna ? i would like to know your results please as i would like to make one also.

thanks.
 
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If you search through this section with the search feature at the top of the forum there is a ton of info on this antenna, including many that have home brewed this antenna


73
Jeff
 
I have made a couple of them with rg213 for the coupling capacitor and rg213 for the matching stub and they work great,, VKRULES gave me the dimensions for all the different sections of the antenna.
 
Sorry for joining the party a little late, any possibility you could post the link again?
Thank you.
There is info on homebrew here:


73
Jeff
 
There is info on homebrew here:


73
Jeff
Thanks for the reply, I had a look through it. For some reason I'm not seeing any links to the info I need. Basically, I want to have a go at the 5/8 gainmaster using rg213 for stub and/cap.
 
Thanks for the reply, I had a look through it. For some reason I'm not seeing any links to the info I need. Basically, I want to have a go at the 5/8 gainmaster using rg213 for stub and/cap.
I've made a gainmaster from RG213, and it worked great. I have some 1/2" heliax here and I've started to make one out of that.

This video should help out a lot

 
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I've made a gainmaster from RG213, and it worked great. I have some 1/2" heliax here and I've started to make one out of that.

This video should help out a lot


Thanks for that mate, I think I've seen that a few times but don't see the rg213.
I've done some digging and found a stub measurement of 561mm. I'll give it a go and see how I get on.
 
Thanks for that mate, I think I've seen that a few times but don't see the rg213.
I've done some digging and found a stub measurement of 561mm. I'll give it a go and see how I get on.
RG213 has a 0.66 velocity factor which is the same as RG58, so measurements should be the same for the lower half of the antenna incuding the cap. In that video the stub is made from Westflex coax so the length of the stub will be different when using RG213 for the stub. The 561mm sounds good to me, have a read through the below thread, the guy worked out what type of coax Sirio used and the velocity factor of that coax. Once you know that you can re-calculate the length of the stub to work with any coax that you want to use. I found it interesting that from the feed point to the end of the stub is a 1/4 wavelength long (when accounting for velocity factor).

Thread is well worth a read...

 
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Or here?


73
Jeff
 
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Or here?


73
Jeff
Thanks Jeff, really appreciate the help.
 
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