Hi Guys.
I have had trouble tuning my 27MHz CB Stationmaster Mk2 antenna. There's about 1.5 Ohms of resistance when measured at the antenna socket between the center pin and outer earth. Is this normal and does this antenna need grounding?
Thanks.
Stationmaster Mk2
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Aussiescanners takes no responsibility for any modification undertaken, these are to be done at your own risk and should only be performed by those with good knowledge of radio and soldering.
Aussiescanners takes no responsibility for any modification undertaken, these are to be done at your own risk and should only be performed by those with good knowledge of radio and soldering.
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Vkfour
- Senior Member
- Posts: 376
- Joined: Tue Oct 05, 2010 11:27 am
Re: Stationmaster Mk2
Why are you measuring the resistance between the centre pin and outer edge? Do you have an SWR meter? The stationmaster antennas I have used in the past were always earthed through the mounting brackets.
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GU Erik
- Newly Registered Users
- Posts: 3
- Joined: Wed Jan 08, 2014 11:08 pm
Re: Stationmaster Mk2
I was chasing a short as I cannot get the SWR down below 3+. I was told that the Stationmaster is ground independent but I may try mounting it on a steel pole to earth it as it was previously mounted on a timber post. The Mk2 doesn't have a mounting bracket - it's U-clamped around the base.
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Vkfour
- Senior Member
- Posts: 376
- Joined: Tue Oct 05, 2010 11:27 am
Re: Stationmaster Mk2
Stationmaster antennas, the ones you buy as opposed to the name of a type of antenna, is basically designed to show a 50 ohm load at around 27MHz, (26 to 28MHz and pretty much anywhere). This will result in a low SWR. There should be no need to tune it at all, unless you want to use it on 10 0r 15 metres. The antenna is basically designed to be attached to steel pole and even ground independent antennas need to work against an earth.
If it doesn't work well on a steel pole, have a look around and see if it is mounted close to any buildings or other structures as this can cause no end of problems. I once moved a 2 metre antenna about 50 centimetres and it went from not working to hyperactive!
If that doesn't work, then you need to have a look at the loading coil in the bottom of the antenna. I haven't seen a Mk2 antenna for real, but the photos look like the base is pretty well sealed.
Let me know how you get on.
73
If it doesn't work well on a steel pole, have a look around and see if it is mounted close to any buildings or other structures as this can cause no end of problems. I once moved a 2 metre antenna about 50 centimetres and it went from not working to hyperactive!
If that doesn't work, then you need to have a look at the loading coil in the bottom of the antenna. I haven't seen a Mk2 antenna for real, but the photos look like the base is pretty well sealed.
Let me know how you get on.
73
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GU Erik
- Newly Registered Users
- Posts: 3
- Joined: Wed Jan 08, 2014 11:08 pm
Re: Stationmaster Mk2
Thank you for the information. Yes the base is very well sealed and the problem could indeed be the location. I have nowhere further than 5m or so from the house to mount it. The house is high-set and also has a tin roof, so I was wondering if this was the cause. I shall try and source a suitable mount/mast setup to get it above roof level and see what happens. I made a simple dipole (approx 2.6m each length) and this was impossible to tune also.
Cheers.
Cheers.