Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: audio poping in and out...using workman magnet.....  (Read 6979 times)
K3NRX
Member

Posts: 2078


WWW

Ignore
« on: June 03, 2014, 06:43:21 PM »

Rig is an FT1802 Yaesu....every repeater I hit, the audio breaks up....this is beyond the typical mobile flutter.....I just picked up a workman magnet for the two meter mobile antenna because the old one was shot and corroded.....I paid $25.00 for this thing....I really hope this isn't the cause of my issue.....I tried tuner cleaner on the magnet contact with the antenna...I tried tightening up the antenna to the magnet....I tried replacing the original PL 259  end connector on the magnet's coax with a new one, soldered up all tight.....I sprayed tuner clear on the radio speaker...all of this, and still I get this audio break up....can someone offer some suggestions as to what this problem is?....again, this is NOT typical mobile flutter....I fear that something is wrong with this magnet, which is NOT good....for the record, this problem happened with my previous magnet as well (the corroded one)......Please advise on what may be causing this....

V
K3NRX

Logged
K5LXP
Member

Posts: 4536


WWW

Ignore
« Reply #1 on: June 04, 2014, 06:52:49 AM »

Several things could cause this problem.  First thing I would do is borrow or build a different antenna and give that a try.  That will tell you right away if it's a radio or antenna problem.


Mark K5LXP
Albuquerque, NM
Logged
KB4QAA
Member

Posts: 2490




Ignore
« Reply #2 on: June 04, 2014, 12:53:37 PM »

I'm not sure what you think the magnet has to do with the transmission quality......

Why would you spray tuner cleaner on a speaker?

All it does is hold the antenna frame to the body.  The frame is capacitively coupled to the body.  Even significant movement, rubbing or bouncing is not going to dramatically affect the signal.

The most likely problem is an intermittent mechanical/electrical connection.

Buy or borrow a known good antenna and coax and test with that.
Logged
AA4PB
Member

Posts: 13033




Ignore
« Reply #3 on: June 04, 2014, 01:57:21 PM »

You probably need a new speaker now that you have sprayed tuner cleaner on it.

Have you tried moving the antenna or coax while listening in order to see if you have an intermittent connection? Does the coax shield have a solid connection to the magnet? The magnet provides capacitive coupling to the vehicle but it doesn't work if the coax is not connected to the magnet. Have you checked the SWR while moving to see if it is bouncing around?


Logged
K3NRX
Member

Posts: 2078


WWW

Ignore
« Reply #4 on: June 04, 2014, 04:04:23 PM »

You probably need a new speaker now that you have sprayed tuner cleaner on it.

Have you tried moving the antenna or coax while listening in order to see if you have an intermittent connection? Does the coax shield have a solid connection to the magnet? The magnet provides capacitive coupling to the vehicle but it doesn't work if the coax is not connected to the magnet. Have you checked the SWR while moving to see if it is bouncing around?




It appears this problem has cleared up (knock wood)....not sure how, but the audio is clean, with typical mobile flutter for more distant signals...and the speaker still works fine...and it seemed this problem occurred both while moving and while being still.....I am under the impression that these magnets are very cheaply made, as I am not real impressed with the silver braid and conductor in it's coax.....

V
K3NRX
Logged
WB2WIK
Member

Posts: 20666




Ignore
« Reply #5 on: June 05, 2014, 01:58:25 PM »

"Workman" is pretty cheap (mostly CB) stuff.  I wouldn't pay anything for any of it.

I took one of their mag mount bases apart a year or two ago to find they were literally using the magnet itself as the electrical contact from coax outer conductor to the outside world, then a think piece of plastic between the magnet itself and the bottom of the mount where it contacts the vehicle.  Then, I checked the electrical continuity of the magnet: Zero.  There wasn't any, at all.

I have no clue how they thought that would ever work. Wink

I use Larsen NMO mag mounts, which use a piece of thin aluminum as the contact between the coax and the vehicle, so there's a large capacitively coupled mating surface, and full electrical continuity between the coax outer conductor and that aluminum.  They work fine, and cost about the same.
Logged
K3NRX
Member

Posts: 2078


WWW

Ignore
« Reply #6 on: June 18, 2014, 09:19:14 AM »

Patched up the antenna which had a gash in it...sealed it with some Goop and covered it heavily/tightly with elecrical tape.....and I am still having the same problem.....Conclusion: it's not the magnets, it's not the antenna, it's not the coax or connections....there is something wrong with this receiver.....Looks like years of being out in the brutal cold has finally taken it's toll....Guess I am gonna have to crack it open and check for loose connecitons and cold solder joints......this is frustrating....

V
K3NRX

Logged
N6AJR
Member

Posts: 9927




Ignore
« Reply #7 on: July 07, 2014, 11:10:04 AM »

goop and electrical tape should make it worse. it would act like an insulator and cut down on the capacitive coupling.  try to ground the shield side of the antenna to ground on the car. give the electricity a return path at RF levels.
Logged
KB2VUQ
Member

Posts: 117


WWW

Ignore
« Reply #8 on: July 07, 2014, 05:17:06 PM »

I hope you painted the goop, magnet and antenna to
match the color of the car. The important thing is to NOT
drill a hole and devalue the vehicle.

Are you the guy from Hamsexy?

Logged
K3NRX
Member

Posts: 2078


WWW

Ignore
« Reply #9 on: Yesterday at 10:46:25 AM »

Reprogrammed the FT1802 to narrow bandwidth which now has brought back my receive....clean reception all around....but something is telling me that this is a temporary band aid and that the wide bandwidth is shot.....any suggestions?....

V
K3NRX

Logged
KB4QAA
Member

Posts: 2490




Ignore
« Reply #10 on: Yesterday at 01:30:21 PM »

Wow, still messing around with this?  Wink

1.  Throw away the old antenna
2.  Drill a hole and install a quality NMO mount
3.  If you decline to drill holes, buy a new quality mag mount from reputable ham manufacturers like Comet, Diamond, etc.

good luck and Merry Xmas!  bill
Logged
K3NRX
Member

Posts: 2078


WWW

Ignore
« Reply #11 on: Today at 06:56:26 AM »

Wow, still messing around with this?  Wink

1.  Throw away the old antenna
2.  Drill a hole and install a quality NMO mount
3.  If you decline to drill holes, buy a new quality mag mount from reputable ham manufacturers like Comet, Diamond, etc.

good luck and Merry Xmas!  bill

No I am not...not since I switched to Narrow Bandwidth....I don't need a new antenna....I bought one at a ham fest last month and the problem persisted.....I wasted $24.00....again, my question is - is the narrow bandwidth a temporary fix/is my wide bandwidth now shot to hell and needs repaired?......I don't understand why my receive would all of a sudden give me trouble on wide and only work on narrow.....

V
K3NRX

Logged
AA4HA
Member

Posts: 1646




Ignore
« Reply #12 on: Today at 08:19:43 AM »

Make sure that you have a good ground connection to the radio. Also that the ground fuse is not blown out on the power cord. It sounds like you are getting an intermittent connection somewhere in the chain.

Those mag-mount type antennas do not get ground through the base metal where the magnet sticks to your vehicle. In fact, you do not want to have an electrical connection at that point. That would mean that the magnets have scratched or gouged their way through the paint layer on the roof of your vehicle. Many mag-mount type antenna bases actually have a vinyl or teflon insulating film on the magnets to minimize the paint scratching.

The crackling, breaking up noise must sound very different than what you have heard in the past. This is what leads me to believe that there is a grounding problem somewhere.

As far as the comments about the "Workman" antennas... yea, they are junk. You may be lucky and get a decent one or be able to modify it in such a way that it will work for you but you should not expect that it is going to be a stellar performer. I use Diamond antennas and Diamond antenna mounts. Even if you do not want to drill a hole for an NMO style mount you can find one that is a edge clip type of mount for an antenna that you can use on something like your trunk hatch lid.

Just one example of a trunk-lid mount with an NMO base;

http://www.diamondantenna.net/k400cnmo.html

And a 2 meter NMO style antenna;

http://www.diamondantenna.net/m285snmo.html

The bracket I have given you an example of will not require you to go drilling holes in your car to mount the antenna. It takes about 10 minutes to install with the little allen wrench that comes with the mount.


Logged

Ms. Tisha Hayes, AA4HA
Lookout Mountain, Alabama
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!