President Grant 2 is it antenna fussy

Been trying for months to get my Pres Grant 2 to operate but no matter where I fit it , EG nin my van or home, no matter what twig I use I cannot get the SWR down. I'm totally baffled and looking around for likely causes. Its never been used operationally though I've had it 3 years because I've never managed to get the SWR under 10.

First off sorry to ask are you new to CB radio?, what antennas have you been using , I presume you are using a antennas that is ment for CB radio use also what SWR meter are you using
can you go through how you are checking your antenna SWR in case your making a mistake.

Saw your reply on other thread, cheers Mate. Following SWR instructions to letter that came with SWR meter, I'm starting to suspect patch leads and cable from Magmount, tried Three different CB antenna from Thunderpole including an 18footer, and a based loaded mobile whip.

On and off I've been into CB since 1976

Ok mate, same here I started 75/76 myself, sorry I had to ask cos I have known some newbies to cb trying to use the car/Van's music radio for cb lol, what about what I said about the roof what material is it made of .

its steel, Transit van roof 8ft by 6ft

Its gotta be a dodgy coax mate ,it might have a break in it or crushed  and it maybe shorting out, let's us know if you sort it out I'll be interested to know what it was

Yes mate I'm guessing dodgy ant cable or dodgy SWR meter or its patch lead, Its a bloody nightmare not being able to visit a shop for spares and advise. I appreciate your help.

BTW I just posted another antenna question if your feeling helpful

Bill

Have you got a multimeter to test the coax for a short.

Trying to borrow one today, mines bust.

Alan Pilot wrote:

Have you got a multimeter to test the coax for a short.

It doesn't have to be shorted to give high SWR. The impedance of coax is determined by the spacing between the outer surface of the centre conductor and the inner surface of the braid. Alter that and it alters the impedance of the coax which affects the SWR.

In mobile installs with high SWR coax pinched or crushed where it comes into the car which measures OK with a DC multimeter has led many a person on a wild goose chase.

Northern Crusader wrote:

Alan Pilot wrote:

Have you got a multimeter to test the coax for a short.

It doesn't have to be shorted to give high SWR. The impedance of coax is determined by the spacing between the outer surface of the centre conductor and the inner surface of the braid. Alter that and it alters the impedance of the coax which affects the SWR.

In mobile installs with high SWR coax pinched or crushed where it comes into the car which measures OK with a DC multimeter has led many a person on a wild goose chase.

I did say to test for a short.
That's the first thing i do then test for continuity after that.
Everybody has there own path of fault finding i suppose.

Alan Pilot wrote:

I did say to test for a short.
That's the first thing i do then test for continuity after that.
Everybody has there own path of fault finding i suppose.

Neither will tell you that you're getting high SWR because of pinched coax so using those alone won't rule out everything. Ironically you don't need a meter to measure it, you can see it with the naked eye. If the coax is flattened, even a little bit, or it's been bent tighter than the minimum bend radius in the specs then that's likely the reason assuming no dodgy soldered on connectors.

A multimeter will tell you if you have the dodgy soldered on connectors as mentioned above.
It will also tell you if you have a stray bit of the outer shield touching the centre cable.
It won't do the swr but will rule out bad connections.