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Triplecguy
Intermediate Member
Username: Triplecguy

Post Number: 226
Registered: 12-2001


Posted on Tuesday, November 06, 2007 - 11:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Is there a 400-600 watt amp that can be driven with a new Magnum 257 with the higher output? I am afraid that if the RF power is turned all the way up on the Magnum, it may be too much for most of the amps on the market except the big competition amps. The Magnum has not been modified at all except for extended transmit. I would appreciate any input as I really don't have a clue.
Dan
N0RAD/Colorado 813
International Man of Mystery
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Splbass17
Member
Username: Splbass17

Post Number: 88
Registered: 9-2005


Posted on Friday, November 09, 2007 - 9:39 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

By the way Triplecguy, to try to answer your question (I'm no expert I learned from these guys). If you want a small amp that has a driver, 1X2,1X4,or 2X4 the 257 is going to over drive it unless your deadkey is under 4 watts, preferably 1-2 watts so you need to check that with a meter before you run it.

Also from what I gather, your probably better off with a straight 4 2sc2879, that way you don't have to mess with the deadkey and you wont run the risk of overdriving your box.

Hopefully someone jumps on here real quick to confirm all this.
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Splbass17
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Username: Splbass17

Post Number: 89
Registered: 9-2005


Posted on Friday, November 09, 2007 - 9:32 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey whats up guys!!! Sorry I haven't been on in awhile I've been away at the NJ State Police Acedemy and Air Force ROTC training (ouch)....... Anyway I have the same exact question as Triplecguy. I had a General Lee w/ a 5 pill box and was very disappointed with only 350 watts pep! So I just ordered the Blue Magnum 257 and wanted to match the perfect amp.

What I do know already is that the a 2sc2879 pill likes 10 watts pep, so I'm thinking a High Drive 4 pill box with 2879's should do the trick considering the 257 swings 40-50 watts (from what I've read). Am I'm right or should I be looking at something else?

I actually wanted the small 2 pill trucker box but I think the 257 would smoke it, so if a straight 4 pill is the way to go then I guess I'll spring for the bigger box after all.
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 3999
Registered: 7-2004


Posted on Friday, November 09, 2007 - 7:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

magnum 257 w/erf 2030's, keep RF carrier below 10 watts, turn mic gain down so swing stays below 40 watts & a dx500v texas star should show near 150 watts carrier & near 500 PEP. i have the new blue 2030 magnum 257 in my truck for 10 meter use only with no amp, but for testing purposes, it's shown those #'s with the 500v, and over 625 watts PEP with a magnaforce m600, with 55 watts PEP input.
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Splbass17
Member
Username: Splbass17

Post Number: 90
Registered: 9-2005


Posted on Saturday, November 10, 2007 - 11:34 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Pat, so my deadkey should be at 10 watts or less for even a Comp HD Box? I'm looking at the FatBoy straight 4. Whats the 257 deadkey at when on low? And whats it deadkeying at on high? (before alterations)
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 4000
Registered: 7-2004


Posted on Saturday, November 10, 2007 - 2:33 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

my 257 does 1 watt at lowest setting & about 14 highest, but i think that's a bit too much, the AM audio gets 'thin' & scratchy up there-that's after i adjusted it, never checked AM out of the box-no biggie though, i don't use that radio AM or CB at all.
the fatboy 4 x 2879 should key 150-200 with the 257, and PEP should be 700+ on AM, a bit less on SSB. no matter what fatboy says, don't go any higher then 200 carrier. PEP could reach 850+ with more drive, but nobody will ever notice 100 watts, so why bother. they suggest driving it with a 1 or 2 x 2290 amp, but that's WAY too much, it won't get you anything more then garbage, and eventually smoked 2879's, with that much input.
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Splbass17
Member
Username: Splbass17

Post Number: 91
Registered: 9-2005


Posted on Saturday, November 10, 2007 - 4:14 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Awesome, I was hoping the 257 would give me a wide varity of deadkey options without having to keep opening it up. Sounds like the FatBoy 4x2870 is gonna be a nice combo!

Its funny, I've been reading on other posts people are running 1x2, straight 2, straight 4, 1x4, and 2X4's off the new blue 257 and they all say its the way to go haha, talk about confusing...As long as I hit that 500-600 watt pep mark safely I'll be happy, although my 2ft Wilson FGT might not (I'll be sure to post any cool flaming antenna pics)
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Splbass17
Member
Username: Splbass17

Post Number: 92
Registered: 9-2005


Posted on Saturday, November 10, 2007 - 4:18 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Oh yea... so to see that 150-200 watt carrier what do ya think my dead key needs to be, high or low ?
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Hotwire
Senior Member
Username: Hotwire

Post Number: 2436
Registered: 1-2005


Posted on Sunday, November 11, 2007 - 3:35 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You need a good watt meter to know for sure but my personal rule is 2 watts deadkey and let it swing. That ussually gets right on or close to a fully modulated signal 1 to 4 power ratio.

Triplecguy, The Texas Star DX500 will work perfect with the Magnum 257!
KEEP IT REAL!
Kenny
cef491(27.115lsb)
2sf491(27.555usb)
Indiana
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 4002
Registered: 7-2004


Posted on Sunday, November 11, 2007 - 3:56 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

the 257 has a variable power control on the front panel. tuning the radio internally 1st, will allow the full range to be adjusted externally....then you'll be all set. like i said, i adjusted mine internally, so from the front control i can adjust it from 1-14, that's carrier on AM. the mic gain adjusts PEP of the radio in either AM or SSB. my suggestion is to ALWAYS adjust radio til you see output amp is recommended for....SO-turn radio external RF power to its lowest setting, & mic gain to ZERO. on AM, key radio with amp on (if amp is variable, have it UP all the way), and adjust radio rf power til amp(dx500v for example) shows carrier output it is safe with, for 500v, that would be 125-150 watts of carrier. then turn mic gain up til PEP stops rising. somewhere in the 500 PEP range it will stop going up. maybe mic gain will be only 1/2 way, maybe 3/4, maybe all the way up, depends on the radio & how it was tuned.
dx500v is a straight 4 pill. davemade, fat boy, x force/magnaforce all make straight 4 pills. you can PROBABLY get away with a 5 pill comp amp, but a TS dx667/667v is asking for trouble with the 257 & 50+ watt capability. you can make the other amps you mention work with the 257, BUT you have to make sure EVERY time you turn on the amp you check radio output & set it for the SMALLER then recommended amp...or else you'll have that NASTY smelling smoke in your truck. as for that 2' wilson....make sure it handles 1000 watts BEFORE you attempt to put more then 350 into it...trust me . i'd start shopping for another antenna if i planned on running ANY amp with the 257.
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Splbass17
Member
Username: Splbass17

Post Number: 93
Registered: 9-2005


Posted on Sunday, November 11, 2007 - 4:51 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Hotwire and Pat, I gotcha now I didn't realize you adjusted it internally to get the wide varity deadkey from the external settings (hopefully mine is tuned close to that already when I get it)

As for the Wilson 2ft antenna yea its only rated at 400 watts hahahaha, I got sick of the Wilson 5000 hitting everything I drove under in my SUV plus it looked ugly so I figured I would sacrifice performance for apperance and run as many watts as I can get away with. They say the 3Ft FGT can handle 750 watts so when I burn this 2 Ft one up eventually I'll be sure to give the 3 FT one a try.

I'll let you know how it all comes together, by the way I'm gonna miss tricking my friends into grabbing the whip of my Wilson 5000 with my 5 pill going through it ... that thing would leave some crazy looking electrical burns.
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 4004
Registered: 7-2004


Posted on Sunday, November 11, 2007 - 8:26 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

' I'm gonna miss tricking my friends into grabbing the whip of my Wilson 5000 with my 5 pill going through it ... that thing would leave some crazy looking electrical burns'-is EXACTLY the reason those who 'DO NOT KNOW' shouldn't play with amps. exposure to RF is something that needs to be thought about. it's one thing to KNOW you are exposing YOURSELF to RF, and the possible consequences, but to INTENTIONALLY do it to someone else is not a good thing, not to mention totally irresponsible.
that said, attempting to put 500 watts through an antenna rated at 400, and probably only legitimately capable of handling 150 PEP for any extended time, will only cost money at some point to replace things....radio, amp, coax, antenna, truck. even the 750 watt 3 footer is not a good choice for 500 watts. if you were sure you could control yourself, use the 2' antenna with the amp OFF, and change it out to an antenna capable of handling 2kw when you turn the amp on. i can't control myself....i deal with my predator and bridges & drive thru's by going SLOW, around them, avoiding them, etc.
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Splbass17
Member
Username: Splbass17

Post Number: 94
Registered: 9-2005


Posted on Sunday, November 11, 2007 - 9:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yea I gotcha about the RF being harmful it was only for a "zap" once or twice, I thought it was interesting,hey did you know if you hold a floresent bulb near your antenna (with a decent amount of watts)it will light it up...pretty cool

Thanks for the heards up about the Antennas though i will only use the 2 Ft with the radio, I'll have to get the 4 Ft. or 5 Ft.(1,000+ watts)for when I use the amp. I definitly appriciate it though man, I would have had no idea it could harm the radio but I guess when you think about it those additional watts would probably be reflected back and give me horrible SWR.
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Triplecguy
Intermediate Member
Username: Triplecguy

Post Number: 230
Registered: 12-2001


Posted on Tuesday, November 13, 2007 - 9:44 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey guys, sorry to interupt your whip grabbing, and bulb glowing, but I guess what I really should have asked is what amps can handle the full output of the new high power 257? It seems that amps either want 1 or 2 watts, or a hundred or more, but not 50. Is this correct? By the way, the new Magnums really talk!
Dan
Dan
N0RAD/Colorado 813
International Man of Mystery
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Splbass17
Member
Username: Splbass17

Post Number: 95
Registered: 9-2005


Posted on Thursday, November 15, 2007 - 3:35 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hahahahahaha....anyway, any amp that has 4 2sc2879's will take the full 50 watts of swing and give you the watts your looking for. alot of brands call them high dive amps/boxes, there's plenty to choose from!
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 4008
Registered: 7-2004


Posted on Thursday, November 15, 2007 - 7:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

dan, a texas star dx500v will work if you keep the mic gain down, and carrier on AM. a magnaforce 4 x 2879 will handle the 257 full power & get you a bit more then the 500.
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Elias
New member
Username: Elias

Post Number: 1
Registered: 3-2008
Posted on Saturday, February 06, 2010 - 7:17 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I want to get a texas star dx500v for my magnum 257 also. My question is, can I run that amp in a stock 2002 nissan pathfinder with no problems or do I have to do some upgrades to my mobile so it can handle the amp?
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 4796
Registered: 7-2004


Posted on Sunday, February 07, 2010 - 12:59 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

where in queens? you really use LSB39? maybe to talk to the CT guys? don't hear much LI/NYC activity on 39, only LSB 37 & sometimes 38.

so.....maybe, maybe not. do you have the 257 in there already? what kind of antenna & coax? do you notice ANY effects from the radio? flashing idiot lights? windshield wipers? anything? have you ever used any radio & any size amp in this vehicle?

what size alternator does it have? if it's around 100 amps, you'll be OK, but should go with the biggest battery you can fit, or even double up on the stocker. you should increase ground wire to at least #6, 6 or better for the charge wire & if the amp can be kept within 12' of the battery-direct to battery, no cigarette lighter hookups here-6 will work too. #4 would really be good all around.

as for antenna....anything that handles 2kw will be just fine, such as wilson 2000 etc. now, i prefer NOT to-ESPECIALLY on NEWER vehicles-use the stock mount with crummy rg59 coax. i wouldn't use a wilson 2000 mag mount but rather a wilson 2000 TRUCKER version, on an aftermarket mag mount which i could CHANGE the coax to MINIMALLY RG8X or LMR240 with as close to 100% shield or better yet even double shield. if you can get it into the vehicle, i'd go LMR400, 9086, 9913 or some other full rg8 size double shield.

once you have that all set & ready to go, start amp off real low & keep an eye out for flashing idiot lights, windshield wipers working on their own, the vehicle running rough/bucking, etc. work your way up a little at a time til you're sure all that RF ain't contaminating the trucks computer & ending up costing you a couple grand to fix.

can't think off the top of my head of any pathfinders usig big watts, but the NJ guy splbass17 used slightly more watts in an xterra i think with no problems.....
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Lonestarbandit
Intermediate Member
Username: Lonestarbandit

Post Number: 105
Registered: 10-2006


Posted on Sunday, February 28, 2010 - 1:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

ok guys, what about 2290x4 amp? I have cobra/skipper/magnum blue face (nice amp btw w 5 pole filtering) 4 power settings....was seeing over 600 pep on max which scares the daylights outta me it is only a 4 pill....is the 257 gonna destroy it? Im dk 2.5 swinging 50 on audio. yes its the fet 257. For now running medium 100 swinging 240 which is pathetic but Im scared for my pills.
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 4815
Registered: 7-2004


Posted on Sunday, February 28, 2010 - 10:23 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

4x2290 should key 80-100 & swing 300-375.......for AM, turn mic gain down to no audio, radio power output to lowest level, turn amp ON in hi power position. key radio, turn up RF power til amp is dead keying 80-90 watts. turn mic gain up til amp swings 350 or so. that's all the 2290's are meant to do with that amp, don't go higher 'because you can'. for SSB, turn mic gain down & radio rf power UP, amp in HI power and/or SSB position (if it has one). key mic-you should NOT see any carrier with mic gain 'off'-then turn up mic gain til amp SWINGS 300-350 on SSB.

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