SWR meter and new set up

Hi all. Looking for some help.  I am getting back into radio after a 40 break and need some advice on a couple of matters. 

Firstly I have a CRT XENON in my car with arial mounted on the roof which is a yellow 1.5m whip (5/8 ? with child at the bottom.  I have tried three different swr meters but can’t seem to get the correct settings. The third one is a dual screen one but still same problems with SWR and Power setting. When trying to adjust the power it only goes to just below the red part and i cannot get it to full.  The SWR sometimes shows <1 and when I check it again it goes up to >2.5. I did try to get a radio check and was told it was 5 - 9.

Secondly I have nearly completed my Foundation course and when I get my license I will be looking to go out and do some serious chats once again (did some cqdx in my truck driving days).
I have purchased a 6900 and a Tracer power pack (after searching for details on what best to use as power pack in the field found this information in a post by club member showing the equipment he carries in his back pack) together with an HF Antenna rated to 250 Watts P.E.P
40 M Single Band Antenna 
Power rated: 200W
Length: 245 cm MAX
Bandwidth: 80kHz
I hope to mount the antenna on an old tv aerial pole (2M length) together with an 18” square plate for ground plane. Will this work ok to get started?
I need to get these sorted so there will be no damage to my 6900.
Thanks in advance

That should say COIL and not child on the antenna (predictive text duh)

I'm no expert on the matter, however the first question i'd be asking is, do you have a stable voltage supply to the transceiver? (Confirmed with a multimeter while transmitting)

Also is it on a mag-mount.
If so it could be the coax connection in the bottom.

Power supply is direct to car battery (new)
And cable came with the mag mount (connected) but will check this again
Thanks for response

A lot of problems like yours is down to the coax connection in the bottom.

Hopefully it's something simple, those fandangled modern radios look a little daunting, I'd bet you'd need more than a steady hand and a soldiering iron if you had to open one up.
Definitely worth checking all the basics first, coax and connectors are definitely worth a look.
Do those modern radios have any stability issues when their cold?

Have checked coax as much as possible and seems ok. Have tried a new mag mount but still getting same or similar results using two different SWR meters

I hope will not lead to a wooden box for my 6900n

Many thanks for your import

I have managed to get the SWR to 1.8 between channels 1 and 40 now by moving to a different location and removing the rubber mat under the mag mount. Have tried to check feed to mag mount but it is a sealed unit and not able to get to the connection.

Just need to know if the equipment I have is sufficient to start field operations please.

just put my tri mag back on the car and sirio 4000hp back on the mag mount and swr the same as last your its summer time again

What power are you pushing into the SWR meter?
I remember having the same "Can't Cal a SWR meter" and (embarrassingly) was only pumping 1/2 a watt into it. Something most would happily work on, only not that make.

Another issue was my trusty patch lead into the SWR meter.
Only that time it wasn't trusty and had an intermittent break in the inner core.

One time running a cable to an 8' fire stick on a large tin plate in the attic, I just couldn't SWR it.
On testing the cable with a dummy load, it had a standing SWR of 5.

I had missed the crush damage 'pulling the cable' had caused.
There was no short, only it didn't work no more.

If you have a dummy load, I always test the patch on the aerial side of the swr meter if it is used a lot in other setups.
I also do the same on aerial leads I ran through my house before attaching them to the aerial.

Having said that, mag mounts are a bit temperamental.

Paul Gray.

Hi I had a similar problem, I just couldn't get my swr down from 2.0 no matter what I tried. That was on my car and frustrated me no end so took my set up indoors to check. I decided to buy 16 mtrs of rg58 and made my own patch lead (2ft) ( last time I made one was @30 yrs ago) and 'bingo' it brought my swr down to 1.1 and the original patch lead was bought from knights. I have now thrown that in the bin and will now make my own patch leads. I was also told that many modern cars are made of Aluminium so that doesn't help with the swr (or are they wrong?) I know my car is. Hope that may help.
       73's

Glen

Thanks for your input. May give it a try making my own patch leads if I can’t get the SWR down. Trying a new SWR meter

73s