antenna help

[Robin1]

I have hooked it up and then the SWR i am getting is over the 3 does any one have any tips and help please

Thanks

[troutboy]

Tell us exactly what you did and what you are doing.

We'll sort it mate.

It could be one of a number of simple problems such as: The PL's not soldered correctly, not srewed in correctly, antenna may need tuning slightly or you haven't set the SWR meter correctly such as the calibration knob or the F/R switch, even a dodgy patch lead, the list goes on.

Just talk us through what you are doing.

[Animal]

Don't panic Mr. Mainwaring!

Is the SWR reading well over three on every channel ??? If it does, there may be a bad connection (coax plugs soldered correctly?)

Check channel 1 & 40 note the readings - what are they?

If your SWR is higher on channel 40 than channel 1 then you need to shorten your antenna.

If it's higher on 1 than 40 then you need to lengthen it.

Adjust the antenna length only in half inch incraments (by telescoping in or out of the top section) But first mark your original setting on the antenna incase you need to go back to it

Any movement?

[Robin1]

well my dad did solder it and made an improvment it went to the set mark on the swr. But i am just going to try and make it bigger height wise on the antenna.

[Animal]

If you got a good conection then you should be somewhere near if you lined-up the marks on each section of the antenna.

To use your SWR meter correctly, get your patch lead (1-2 feet of coax with a PL plug at either end) & then plug one end into your rig and the other into the SWR meter socket marked TXMTR (or similar)

Then plug the coax that comes from your antenna into the other socket on the SWR meter marked ANT (or similar)

Turn the knob on the SWR meter all the way down, then put the switch in the FORWARD or CALIBRATE position.

Press the mike button (keep it keyed) then adjust the knob until the needle is on the SET mark - (keep it keyed) - then flip the switch to the REF or SWR position & note the reading - you can now un-key the mike & do the same on channel 40 & note this reading too.

Adjust (antenna length) as neccesary.

[Robin1]

I know how to do that but i am getting the same reading, however i did a 1:3 reading for only a little while though.

[Robin1]

How do i tune a silver rod?

[5thElement]

Adjust the length of it by moving the bottom section up/down.

Ie, hmm, how do i explain this...you have the bottom section...then you have a section slipped into that and held with the jubilee clip....loosen the clip and slide the 2nd section up/down as appropriate and retighten it...test again...keep going until you get the swr down.

Keep this in mind while doing this

"If your SWR is higher on channel 40 than channel 1 then you need to shorten your antenna. If it's higher on 1 than 40 then you need to lengthen it."

You might not get it down to 1:1, but anything under 1:5 is fine.

Let us know how you get on, it was a pain in the arse when i first did this years ago, and i never had the internet back then to ask questions! lol

[Animal]

however i did a 1:3 reading for only a little while though.

hmmmmmmm - you mean it changed without you doing anything to the antenna?

If so try moving the coax at the rear of the meter & rig whilst keyed up - if it fluctuates you have a bad connection at the radio end (most likely one or more of the PL plugs) and you shouldn't keep it keyed for long.

If you put the antenna together correctly and all the PL plugs are soldered correctly you should still see a SWR reading less than 3:1

At a 3:1 reading you'll be losing 25% of your power (or 1 watt from a 4 watt radio) so ideally aim for 1.5:1 or below which is about 96% efficient.

Keep tryin'

[Robin1]

Could it be the length of the wire because i have a 30-40 feet wire on the ground ready to be pinned up.

[Animal]

Wire

If you mean coax - then perhaps, but only if you have it coiled up (I take it you have 50 ohms & not TV coax - seriously I've seen this )

Three or four loose turns will be okay, (it might even act as a RF choke) but 40 foot coiled up isn't good

Can you receive anything at all?

[Robin1]

I did mean coax 50 ohms. But in the Transmission1 guide to swr meters it tells you that length of the coax has not got anything to do with it? only power.

I did manage to get it down to a 4.

I can't receive anything yet

[Animal]

It's not the length - it's the fact that it may be coiled up.

Anyway, if you're no receiving anything at all then I think the antenna length is definately not the problem (even with a high SWR you should still be able to receive to a degree)

To confirm this, remove the coax from the back of the SWR meter for a moment whilst the rig is switched on (you should definately hear a change in the noise level - even if there is nobody on channel)

Get an Ohmmeter & put the red and black probes (use Rx1 scale) across the coax connectorfrom your antenna (one on the center pin of the PL & the other on the shell) & it should show a DC open (no reading at all) if it deflects you have a short - probably caused by the outer braid from your coax touching the center condutor in one of the PL plugs.

Check the connections again - re-solder the PL plugs (make sure there are no stray wires from the braid touching the center conductor) Then check you have all the marks on the antenna aligned in the correct place.

If you've done all the above you should be somewhere near

[5thElement]

Keep listening on channel 19, you should hear something sooner or later!

Best of luck

Keep us updated

[Robin1]

Thanks alot guys for the help.

I have found a friend who says he can do the soldering which is alot better than me doing it i am rubbish.
HA HA