| Author |
Message |
    
Excope
Junior Member
Username: Excope
Post Number: 22
Registered: 8-2004
| | Posted on Tuesday, January 04, 2005 - 9:56 pm: | 
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I know Magnum makes some of the best power cord filters you can buy but unfortunatly they don't make one to fit my Magnum 257. So my question is, who does make one? If Magnum does make one to fit the power cord plug of the 257 where can I find one.
Thanks, Excope, CEF 386 |
Tech808
Moderator
Username: Tech808
Post Number: 4469
Registered: 8-2002
| | Posted on Tuesday, January 04, 2005 - 10:40 pm: |
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Excope,
GOOD NEWS,
Yes they Do Make Them and Copper carries them. 
We use them our Magnum S-45 and New Magnum 257 both. 
MAGNUM has been making them now for well over 1 - 1/2 years now.
JUST CLICK on the LINK Below:
http://www.copperelectronics.com/cgi-bin/checkitout/checkitout.cgi?catalogSTORE:CKIE:prodP03-01095+
**********
P03-01095 PLF-10M Power Cord w/Filter
$ 19.99
When you have Noise coming into your radio through your power cord, this is what you need.
FEATURES:
For Use With White 2 pin connector for Magnum and Millennium Transceivers (Not for 357)
Transceiver Power Cord with Integrated Power Line Filter
Replaces Your Transceiver's Stock Power Cord
Eliminates Alternator and Ignition Noise Problems
Improves the Receiver's Signal-to-Noise Ratio
Inline Fuse to Protect Transceiver
Over 7 Feet of the Highest Quality 14 Gauge Cable
10 Amps Maximum Current Handling
Operates from 6 - 16 Volts DC
**********
NOTE!
The Picture in the Ad shows the Wrong End but it will fit the 257 and S-45 Radios with the T Plug.
They will work with all of the New & Older Style Magnum Radios with the T Plug as well as other radios that use the T Plug.
They will not work with the MAGNUM 357
Lon
Tech808
CEF808
N9OSN
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Excope
Junior Member
Username: Excope
Post Number: 23
Registered: 8-2004
| | Posted on Wednesday, January 05, 2005 - 2:41 am: |
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Thanks, Lon. The picture in the ad is what had me thrown off, and the fact the ad dosen't mention the T plug end. Thanks again.
Excope, CEF 386 |
Gijoe
Member
Username: Gijoe
Post Number: 57
Registered: 4-2002
| | Posted on Saturday, January 08, 2005 - 10:09 am: |
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I ordered a filtered power cord when I ordered my 257. I here more alternator and ignition noise in the 257 with the cord and the NB turned on then I did on my Uniden 76 with no filtered cord and the NB turned off. I also have a Yaesu 2800m with the same t-plug on the end. I can unplug the 257 from the filtered power cord and plug it into the Yaesu cord, which is not filtered, and I can't tell any differance on the alternator and ignition noise level. |
Tech808
Moderator
Username: Tech808
Post Number: 4506
Registered: 8-2002
| | Posted on Saturday, January 08, 2005 - 11:00 am: |
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Gijoe,
Just Curious,
What kind of car/truck ~ Ford/GM/Chrysler product?
Where do you have your radios grounded to in the Car/Truck?
Where are you drawing the power from for the Filter Cord?
What kind of antenna are you using and where is it mounted and is it grounded?
Lon
Tech808
CEF808
N9OSN |
Racer X (Unregistered Guest)
Unregistered guest
| | Posted on Saturday, January 08, 2005 - 11:37 am: |
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If the noise goes away when you disconnect the antenna it's not coming through the power cord, it's coming through the antenna.
To get rid of the noise you should start by grounding the hood of your vehicle VERY well and that may shield the noise well enough to keep it out of your antenna.
If that doesn't work you'll have to track down what's creating it and address it as needed. Bypass capacitors and RFI supression ignition wires are probably in order. Today's high voltage ignition systems and multielement spark plugs (splitfire spark plugs !#*%#@!!!!) create so much RFI it's not even funny.
I owned a 1983 VW Quantam Turbodiesel that was dead silent as far as RFI was concerned. No ignition system because it's diesel, and the alternator was already RFI supressed so the only thing I had to do was use bypass capacitors for the windshield wiper motor and the fan motor in the cabin. While driving down the road I could turn off the noise blankers on the radios and hear nothing at all - except for the noise coming from other vehicles! |
Gijoe
Member
Username: Gijoe
Post Number: 58
Registered: 4-2002
| | Posted on Saturday, January 08, 2005 - 8:26 pm: |
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Lon,
I have a 2000 Chevrolet Silverado x-cab. I have a 2 AWG welding whip running from both the positive and negative battery post, through the firewall, and up under the back seat. The positive lead is terminated to a fused distribution block, and the negative is terminated with a non fused distribution block which supply the power and ground for my radios. I am running a 102" SS whip mounted to an aluminum bracket, bolted to an aluminum toolbox, which is bolted to the floor of the bed with a braided bond ground wire bolted to the bracket, to the box, to the bed, and then to the frame. Here is a picture of my antenna setup. The ground wire is lower on the bracket, so you cant see it in the picture.
http://www.copperelectronics.com/discus4/messages/29/73158.jpg
Racer X,
I haven't tried disconnecting the antenna. I will see if that helps.
Thanks for the suggestions.
Joe |
Yankee
Intermediate Member
Username: Yankee
Post Number: 365
Registered: 7-2003
| | Posted on Saturday, January 08, 2005 - 9:31 pm: |
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'89 Mercury Sable, using a Cobra 138XLR, K-40 Trucker antenna mounted on the trunk lid, using #10 wire direct from the battery. I run mostly sideband and I'm getting all kinds of electrical noise in the receive, mainly from the electric fuel pump in the gas tank, also off the wipers and directionals. If anyone can help me with my noise problem, I'll listen.
Thanks in advance |
Patzerozero
Intermediate Member
Username: Patzerozero
Post Number: 323
Registered: 7-2004
| | Posted on Sunday, January 09, 2005 - 12:12 am: |
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when i 1st tried S9 in my durango, engine noise made magnum unusable in truck. yet grant xl had minimal , if any noise, except when heater motor was on. then it too was unusable. got the magnum filter & noticed little if any improvement. change from wilson 2000 on single 5" magnet to astatic 3kl on same magnet eliminated most noise. change to a 3 magnet mount & some awesome rg8X even cut most of the heater noise out. with ONE HUNDRED watts, FRIED amphenol connector on coax along with arcing at bottom of 3kl and at whip to shaft mounting point, actual popping noise and sparks. at about same time had noticed static and engine noise had returned with a vengeance. replaced coax end, took apart mount and antenna, scrubbed & wire brushed til eveything was shiny again, liberal coating of penetrox on everything & swr's are close again(too cold & rainy to do final tune right now)and everything works. except filter. noise was normal/quiet without filter, but with it-forget it! after i removed it and swung it by it's wires onto the driveway til it required depositing in the garbage, i put a new filter in place-it worked better then the 1st did.
there was not a hint of noise being generated by anything in the truck. now, 2 days after reinstalling everything, i hear popping in the receive, only on SSB with the filter, remove filter & popping is gone....where's my big hammer! |
Racer X (Unregistered Guest)
Unregistered guest
| | Posted on Sunday, January 09, 2005 - 8:01 am: |
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Yankee - If you still hear the noise when the antenna is disconnected then it's coming in through the power leads and a good hash filter should help. But if it goes away when the antenna is disconnected you'll have to try solving the problem at the source. Ground the engine hood with wire braid at the hinges and that may solve most of it, but if it doesn't you're looking at using bypass capacitors at the source to eliminate the RFI.
Ford's are known for the fuel pump in the gas tank causing interference. You can check with the dealer if there is a newer design that doesn't have the RFI problem. You could also try a feed through filter capacitor on the power wire as close to the fuel tank as possible. That will at least cut down the length of the radiator of the noise and while it may not eliminate it, it'll at least lower it a bit.
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Tech237
Moderator
Username: Tech237
Post Number: 125
Registered: 4-2004
| | Posted on Sunday, January 09, 2005 - 11:44 am: |
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Yankee,
Try lacing ferrite beads on the positive lead to the fuel pump. Also place a 10uF capacitor from the pumps positive lead to ground. For safety you might add a 1K resistor in series with that cap - reduces current if capacitor shorts out for any reason.
If you have any loose power cable to the radio wrap it around a ferrite donut so that half the donut is wound clockwise and the other half counter-clockwise. This should take care of any noise that is comming in via the power cable.
You can also wind any slack in the coax on a donute the same way to reduce noise from the antenna.
Using these methods I have taken vehicles with S9+ noise and turned them into quite (S1 or less) radio shacks. |
Yankee
Intermediate Member
Username: Yankee
Post Number: 367
Registered: 7-2003
| | Posted on Sunday, January 09, 2005 - 2:41 pm: |
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Thanks for the advice guys, I might even try my Uniden Grant XL first before going into trying these avenues. I have one more question although. This new Cobra 148-GTL-ST made in China. Is it double conversion like the older 148 GTL and Grant XL? I just in the past 2 weeks added a 148-GTL-ST to the collection and might even try this radio in the mobile. Again thanks for all the good advice. |
