Don't like the adverts?  Click here to remove them

SWR !?

ignat

Well-Known Member
Joined
Mar 22, 2010
Messages
524
Garage
Country Flag
south_africa
Well I installed a CB unit but I'm having trouble with the SWR reading. It is going right off the chart on every channel. :evil:

The CB is wired to a cigarette plug. The antenna is a Mini Tornado Stinger - 88cm - on a mag mount.
No matter where I put the antenna the SWR is the same.
I havent started cutting the antenna - wonder if the cause is something else before I start cutting it..

Advice? :roll:
 
ignat said:
Well I installed a CB unit but I'm having trouble with the SWR reading. It is going right off the chart on every channel. :evil:

The CB is wired to a cigarette plug. The antenna is a Mini Tornado Stinger - 88cm - on a mag mount.
No matter where I put the antenna the SWR is the same.
I havent started cutting the antenna - wonder if the cause is something else before I start cutting it..

Advice? :roll:
Hi ignat



but basically, you have a switch, and a knob on the meter, connect the rig to the transceiver side of the meter and the antenna to the "ant" side !

key up and the switch in the "cal" position, then adjust the knob till the needle goes to the cal position(usually the highest reading on the scale) then de-key and move the switch to the SWR position than re-key and it will read the SWR.

Some meters are slightly different but most are as I have explained

I suspect it is how you are using the meter, please describe how you are using the meter ? and what type of meter ??

Radiotwo
 
There is another thread which also explains it.

I don't think you need to cut your antenna. There should be a grubscrew which you loosen to adjust the length.

Try as Steve says first and see if perhaps you just reading it wrong? They normally set "almost ok" from the shop.
 
Thanks - i've read through the other topic here and also cb4x4's FAQ 's so i think i'm doing it right

I'm using a swr unit from Maplin. Moonraker SWR-100.

Yes, I've connected antenna to ANT part of meter, and then CB to TRANS using patch leads.
Then I calibrate on FWD when keying the mic until the needle is on 'SET'.
then I put it on REF and key the mic and it swings wildly to the right. The CB (Midland 78+) was set to EC. Changed that to UK but still the same.

I hope it is something simple I'm doing wrong, but I cant figure out what
 
Sounds like you might have a bad cable or connector, either to the antenna or the patch lead. Do you have access to another antenna and / or patch lead you can try?
 
Don't like the adverts?  Click here to remove them
I'm in Sutton, Surrey. No no dummy load. I think i will need to exchange the cables and see if that does the trick
 
Ignat,
I am pretty close to you (New Malden/Raynes Park area) and I have 2 antenna that byou're welcome to try. One is a mini-stinger and the other is a longer "modulator". I bought the longer one because the mini-stinger was poor with my CB set-up. Haven't tuned the modulator yet... but no reason for you not to give it a bash to test your radio ;)

Cheers,
 
I think either take it back or try Andrew's aerial. It does sound like either the aerial is open/short or the cable/plug is dodge.
A word of caution though, don't do it too often and not for very. A bad SWR can pop your transmitter. They really don't like it.
 
Do you have a multi meter, you could test the leads for continuity and shorts.
 
Well I've still got the same problem. :?

I took each item back to the shop for replacements and the problem still persists. New SWR meter, new antenna, new CB, new mag-mount. I tried earthing the power cable differently, no help. I also checked the patch leads & coax cable for continuity. All OK. No shorts. Then again I am no electrician so I must be missing something.

I will bring the setup to Salisbury plain tomorrow and maybe someone can cast an educated eye over it if we have a few spare minutes before departing? :?: :p
 
UPDATE:

All sorted. Crispin kindly had a look and found the problem within minutes. :lol: :oops:

Turns out both SWR meters that Maplin provided me were labelled incorrectly. (FWD / REF switch labelled wrong way around....)

So lesson learned: Do not buy Moonraker SWR-100 meters from Maplin. useless.

Thanks again Crispin. :)
 
No problem. Pretty weird that it was like that. More so seeing this was a replacement. I guess maplin got a batch of dodgy ones ;)
 
Back
Top