Sorry for joining the party a little late, any possibility you could post the link again?Here's a link . lot of info including dimensions for other bands.Transmission1 • View topic - Homebrewing a Sirio Gainmaster using RG58 and 2.5mm wire. Great ant .Exceeded all expectations .
There is info on homebrew here:Sorry for joining the party a little late, any possibility you could post the link again?
Thank you.
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.There is info on homebrew here:
home brewing a gain master ???
im not really interested in making a gain master , but i was wondering if anyone has thought about doing it . assuming there is no secret sauce in it it looks like its just coax with a RF invisible sleeve to hold the coax vertical and some metal at the bottom to attach to a mast . $180 plus S$H...www.worldwidedx.com
73
Jeff
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.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
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).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 Jeff, really appreciate the help.Or here?
1.5 KW PEP Gain-Master Modification
So far the only legitimate complaint about the Gain Master has been its power handling capacity. Its high tech design does deserve credit for the gain it produces on the horizon. Originally they were advertised at 1 KW for short periods. After some failures in the first production runs this has...www.worldwidedx.com
73
Jeff