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Alternator may be too small

M

meanoledaddy355

Member
Nov 25, 2012
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I drive a 2012 Kenworth T700 with a paccar motor in it. These motors have small alternators on them. About 125 amps. I want to run an 8 pill but I'm afraid the alternator is too small. I thought about getting a motor maul but want to check my options before I go that route. Its a company truck so I can't install a larger alternator. Will use a smaller amp as a driver or a big radio. Thanks for your help.
 
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I wouldn't do the motor maul thing...it is a band aid approach at best. Remember every time you doulbe your power you only go up 1/2 of an S unit on the other end. Why not take the money and get yourself a good radio, and a nice 4 "pill" amp like a texas star dx-500 instead of a copper clad board splatter box? You will have less issues and still have a great signal! An RCI-2950dx and a texas star 500 would be a nice mobile set up. If you are into AM and echo and roger beeps then a Stryker 440hp would be a good match with the same amp.
 
I had a 2×4 fatboy, it didn't bleed over because it was properly installed. I favor class c amps over AB amps, I think they perform better. If the 8 pill is too much then I may go back to the 2×4. Thanls
 
125 amp alternator's not going to cut it with a 8 pill...You would need at least a 200 amp, and even then you would be cutting it close by the time you added your driver.

As for the Motor Maul. Those may not be the best way to go, but I know several who have had good luck with them.

I know Budweiser Kid runs either a 16 pill or 24 pill with one in his Big Rig, only thing negative he told me was it created allot of heat...Sorta like having the heater on year round.:D
 
A 2x4? Oh yeah I know those things....completely over driven IMD spur boxes that make wattmeters look good and have only a fraction of the actual power output they show in band or on frequency. Someone's pocket gets fat from those.
 
A properly AB biased and driven 2x4 can sound good, and they generate the same amount of wattage as a class C 2x4 but the problem with AB biased amps is two-fold... inefficiency and they generate more heat. They require a lot more amperage to achieve the same amount of output than class C. If you're going to just run AM I don't think I'd go class C because of the splatter, but class AB would be overkill (I'd still would rather run class AB but that's just me) you could go class B and be ok. A straight 8 pill with a driver is gonna probably need in the range of 250-300 amps @ class B.


Just my .02 worth. :tongue:


~Cheers~
 
At At Exit...not trying to upset anyone. That really isn't my intent. Sometimes words on a screen are hard to get the "tone" from so I hope not offend..but....

A class AB (no such thing as BJT AB1) would actually be worse in my opinion if it's a 2 x 4 because a class AB amplifier actually has more gain. While this config in class C (no negative bias applied but no positive either to even though it is not deep into class c it is nevertheless) a 2 x 4 design is still completely overdriven and out of control either way. It can make a watt meter look good but that's about it. Remember that a class C amplifier for anything but FM that isn't directly modulated is going to already have massive amounts of by products and wasted power. Then, overdrive it beyond ridiculousness and the results are just that. While it is true that a class AB amplifier operating properly will draw more current at least you know that what you see on the meter is actually useful for the most part. Worried about the heat? Solve that by proper design and cooling as well as not driving it to the point of meltdown and because you don't have those two extra transistors in there you are already saving some current draw and heat vs if you had them and they aren't doing much for your signal.

See..some really smart people get together and design these things and are aware that they aren't right but don't care. They have a hate and discontent when people like myself come out and tell it like it is.

The builders of even some of the old tube stuff such as Elkin and D&A used to use such "tricks" to fool people using purposely "loose" bias or screen supplies to cause a lot of."swing" on a meter. One of them I have met and when asked got a big smile on their face, laughed and stated that if people will spend the money not knowing any better he will laugh all the way to the bank.

Just run a good amp, a good clean radio, and most important a good antenna system and have fun.

Myself I have in the past been offered money to go to the "dark side" and even partner up with some of these guys. I refused and quite frankly all they do is push junk and use marketing and customer loyalty (no one wants to be told or admit or accept that what they bought isn't good..the powerful thing called pride) and they know that. Anyways..I will back out of here and not say any more.

Ultimately it is your decision and your wallet.
 
meanoledaddy355 said:
I had a 2×4 fatboy, it didn't bleed over because it was properly installed. I favor class c amps over AB amps, I think they perform better. If the 8 pill is too much then I may go back to the 2×4. Thanls
Click to expand...


Any amplifier must be properly installed, that has NOTHING to do with bleed over. A class C 2x4 is a crappy design in the first place if you want to run clean. The only chance you would have had to minimize splatter with your 2x4 would be to way way under drive it with like 8 watts PEP.

The only thing class C amplifiers do better then a nice clean AB amp is show you "feel good" watts on your meter. And splatter all over the band. Your probably running a 40+ watt Export into your 2x4, lol, and your gonna try and say it don't bleed?

And by the way, why do you keep deleting all your fist posts in a thread you start?
 
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Thanks for the valued input. I find that there are lots of radio buffs out there who like talking DX and playing with radios as a hobby. Unfortunately lots of people are not that well versed in the world of radiodom; it does help to have some working knowledge of what your hobby is, but not esential when the goal is to have fun. You learn as you go. Lots of people love race cars as a hobby but know nothing about how to actually drive one or repair one. Unfortunately there are unscrupulous techs out there who will take advantage of honest hard working people who want nothing more than to talk skip. Benevolent, articulate and convincing sounding techs are ripping unsuspecting people off at an alarming rate. Does everybody need to have an MOS as communications specialist in the army then open a CB shop when they become civilians in order to avoid the snake oil salesmen? Predatory radio techs are ubiquitous and can be found mostly at truck stops. To level the playing field some, there is a blacklist available to see who these guys are. At the end of the day, most people are completely unaware that their hobby and converted 10 meter radio are illegal and at the very least a novice license is needed. This illegal am law for the most part is overlooke by many and ignored due in part because the laws governing FCC regulations are vague and obscure. They simply don't go after you like they do drug dealers and murderers and the penalties are not as steep. People like myself want to have fun and not be victimized in the process. There is a thin line between obeying the law and wanting to have fun in spite of the law.Charming and charismatic techs will ostensibly act as though they are helping you, but in actuality they're not. So I say to all the novices out there, try and do some homework when it comes to radios. It's a whole subculture and its going to have its fair share of people who will hate. You must understand you can't be all things to all people and everybody doesn't want to be your friend. So be careful. I'll see you on the radio, 355 waving and I'm back quiet.
 
9C1Driver said:
And by the way, why do you keep deleting all your fist posts in a thread you start?
Click to expand...

Been trying to take care of that issue.

meanoledaddy355, there is NO good reason to delete your original posts in a thread that YOU start. If what YOU post leads to someone saying something that YOU don't like or agree with then tough. Live with it. As you see, the original posts can always be reinstated by an administrator.
 
So far there is no good reason too. We do not lock something unless there is a reason and the thread is going down hill. Requesting a thread be locked is not a valid reason. If the thread goes downhill then further action will be taken. We aren't thread nazis here but we do try and keep things civil.

Ooopss.....Hi Jeff. Didn't see you posting here while I was doing the same.
 
I don't want to post here again. This site is clearly biased toward people who are not Ham operators. So please unsubscribe me from this forum. And if possible remove any of my content
 

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