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magnum 257

what kinda noise ya talking about.how did ya have the
midland wired up for power?cause maybe what you were
experienceing was electrical noise in which case NO certain
brand of radio will fix that.gotta fix that at the sourse of the problem.was your friends 257 that ya said had noise do you know how he has it wired up.magnum also makes a fairly cheap noise filter cord aswell.if the noise problem is electrical.
 
my 2 were run as base radios, no electrical noise was present.
 
It's run directly off the battery, and I even tried installing an inline noise filter and ferrite chokes, but nothing helped. It's definately picking it up through the antenna, because I can hear the ignition systems of other cars driving by me, neon lights, power transformers, streetlights, etc.
I have my Grant XL in the vehicle, laying on the seat, right now, and it does'nt have that problem at all, but the problem with the grant, is I have no place to mount it.
 
well the grant does have a quiet reciever i run same radio
in my mobile.ok dumb question are ya using the nb/anl.
what happens when ya disconnect the antenna?if ya
havent tried that try it see what happens.when was the last
time ya had a full complete tune up on the mobile
plugs
wires
cap
rotar
a good full tune up sometimes helps but not always.as far as
other vehicles i wouldnt worry about that my grant picks up
ther peoples electrical systems but not mine
 
OK, when I disconnect the antenna, ALL noise goes away. The truck just had a complete tune up. If I'm driving down the road at 60 mph, I get 30 dBs noise on the midland, and if I go to neutral, and shut off engine at 60, it gets quieter, but as I go past power poles, lights, etc, I still get 30 db of noise, shzshzshzshz----shzzzshzzzzzhsszzzz-----shzzzshzzshhssshzshzshzshzzzzzzzzzzzzzzshzzzzz-----shzshzshz-shzhshzshz--- like a staticy buzzing noise.
I don't get that with the Grant, of course the grant DOES have a great recieve, and the midland does'nt have a switchable ANL/NB and the way it acts, I wonder if it has any noise filtering at all!
 
frmboybuck said:
Thats the nature of the magnum radios.....They pick up alot of electrical interferance
Click to expand...

Heck, that's the nature of all the exports. The Magnums are very close copies of the RCI/Galaxy genre, when it comes to the RF circuitry. The differences are mostly cosmetic and gimicktry like the "TopGun Modulator" and such. (I know Tech808 thinks otherwise, but he's full of shit.)
 
the midland probaly doesnt have much filtering if any.
when ya rev up the engine does the noise gets worse.
thats uaually the altenator noise.but id thnk if it was youd still hear it even without a antenna cause the noise would still go
thru your power cord which is connected to the battery.which
is hooked up to the altenator.
what type of antenna?
did you add extra power cord to exsisting stock cord
if so what gage of wire
have ya ever replaced the altenator
 
It does get worse when I rev it up, and yes, I can hear the alternator, as well as the spark plugs, but it goes away when the antenna is disconnected. The wire I used to bring power to the radio, is either 12 or 14 guage, and I have a ferrite choke with 3 wraps about an inch from the radio.(did'nt help at all).
The alternator is original, but spark plugs,wires, cap/rotor have all been replaced recently.
I really think it's the lack of filtering, or just an all aroung bad recieve section, because I've tried the grant, 148 gtl, galaxy 959, realistic 450&451, magnum M-1, and president JFK, and none had the problem. I do hear some noise in ALL of them, but nothing like I get with the midland. It's so bad, that it drowns out some of the big base stations I talk to at less than 5 miles away. With the other radios, I can hear the same stations at my house, which is over 30 miles away.
That's why I am curious about the 257. I read in my searches that people complain about the noisy recieve, and it's the only other radio that will fit in my dash hole. I might just have to bite the bullet, and buy it. What's the worst that could happen? it could be noisy, and just re-sell it.
 
yea thats about right.im sure the 257 will have better
filtering then the midland.it should be closer to some
of the others ya listed above.so with that being said
will it have noise im sure yea im sure it will have a tiny
bit as most do but shouldnt be to the point were ya cant
hear 5miles away with big bases as ya posted above.
another question is are ya into ssb.if not the magnum mini
is even cheaper only downside is no freq.counter but will
definately fit in space ya want it in
 
I had both the 257 and the midland 79-290 in my jeep. They both picked up a lot of motor noise, mostly alternator and fuel pump. However, the 257 had far worse adjacent channel rejection. The 257 sounded really good with an aftermarket mic, but the IF gain was just waaaay too hot. I always like the 257 / titan radios for their receive and features packed in a small chassis, however the RX just wasn't that hot. I filtered the heck out of everything in my jeep and just made marginal difference. I never tried the newer 257's but I would love to get one again to play with.

For what it's worth, I used to talk on ssb on 10m all the time with my 257 with a noise cancelling road devil mic. I got the radio because I couldn't afford anything better after I got my general license but I wanted to get on HF. I used to talk all over the place on 10m ssb with that radio and an AB biased 2x2879 amp. You wouldn't believe the compliments I used to get from the other ham guys. ;) ;) ;)
 
In response to the electrical noise issue in the mobile, I would suggest you experiment with bonding/grounding.
I have 4 vehicles with radios installed and have no problems with alternator whine or ignition noise. One vehicle is a Ford Ranger, known for producing noise from the fuel pump.
Another vehicle is a '96 Chevy Impala SS with massive performance upgrades. My Magnum 257's receive is nice and quiet.

I have bonded the vehicles extensively to eliminate noise interference. Large braided tinned grounding straps have been bolted to the different body components in order to bond the vehicle's body into one large surface, the exhaust has been bonded as well, and in the case of the Ford, ferrite cores have been placed around the electrical leads to the fuel pump.

It is true that some radios are more susceptible to noise in a mobile enviroment, but that just means we have to do more to quiet them down.

Here is a picture I took when I was working on grounding the Impala.
SSREARsm.jpg
 
Yeah, I did ground quite a bit, but I must need to do more.
My other vehicle is a ranger, also, and I have that annoying fuel pump whine. Could I just use one or 2 of the snap on ferrite cores over the wires right before they go into the tank, and do they have to be wrapped?
 
I got away with the snap on ones, but in reality it would probably work better being wrapped, but in my case that would have required dropping the tank, yada yada yada.
 
is the Radioshack HTX-10 the same radio as the Magnum-257 and the Uniden 122. can you do the same mods and does it have the same auuuuuuuuuudio as the Magnum 257. :roll:
 

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