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KL 203P install, first timer

" 1w swinging 8-14w? whats that 500% modulation or something? Crazy man !!!

KL 203p is 10/20w input, not 4/8 like previous kl200, so 2w AM swinging 8w or 100% modulation and about 12w SSB pep is well within its limitations and RM's over expectations, expect about 60-70w out at most. "


I have owned two of the red KL203 amplifiers. On AM a 1 to 1.5 watt carrier with any where from 8-14 watts peak worked fine. On SSB it still ran great at 16-18 watts PEP but got warm fast. Something like 10-14 watts peak on SSB again worked great.

Two other people in the area ran theirs with a 3 watt dead key and right at 20 watts peak. Both were toast after about a month. Sorry Jazzsinger you are having problems grasping this, but to each his own I guess. I am just trying to make a positive suggestion so anyone running a KL203 will sound great and their amp will last.
 
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Its not. 1.) Buy an amp and hookup kit. 2.) Put the amp in the vehicle, run the positive wire to the battery and the negative under the carpet by the seat bolt attach to the metal for ground. 3.) Hook you antenna to the amp and hook a jumper from the amp to your radio. 4.) Set your dead key and check swrs.
 
you forgot about: checking your swr at the radio when keying into the amp, and its not just the dead key on am, its the pep also on am and ssb if it has it
 
Thanks nick. I just need to get a hookup kit, that'd what I'm finding to be difficult because I dunno what all I need exactly in terms of fuses, gauges, connectors, etc.

My 959 deadkeys at like 4 watts and swings to 5. Low modulation for sure even with power Mic.
On ssb it gets to 12.
(this is all on the internal meter, don't have an external)

I would just set the deadkey to 1 with the rf power knob when the amp is on... If it burns up, oh well, I tried.
Not really worried about swr, that Wilson is low every time I check it. Never gets above 1.5
 
10 Gauge Hook up kit

20 Ft. of Positive 10 Gauge Wire
20 Ft. of Negative 10 Gauge Wire
Fuse and holder
2 ring terminals

Price: $24.99

Xforce website

Should have everything you need ND88
 
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" 1w swinging 8-14w? whats that 500% modulation or something? Crazy man !!!

KL 203p is 10/20w input, not 4/8 like previous kl200, so 2w AM swinging 8w or 100% modulation and about 12w SSB pep is well within its limitations and RM's over expectations, expect about 60-70w out at most. "


I have owned two of the red KL203 amplifiers. On AM a 1 to 1.5 watt carrier with any where from 8-14 watts peak worked fine. On SSB it still ran great at 16-18 watts PEP but got warm fast. Something like 10-14 watts peak on SSB again worked great.

Two other people in the area ran theirs with a 3 watt dead key and right at 20 watts peak. Both were toast after about a month. Sorry Jazzsinger you are having problems grasping this, but to each his own I guess. I am just trying to make a positive suggestion so anyone running a KL203 will sound great and their amp will last.

Kl203 and KL203p are different beasts, The only one struggling to grasp what a clean AM signal is is you, anything over a 4:1 swing ratio is overmodulation and most definately not clean, 3w swinginging 20 is far from 100% modulation, SSB has roughly a 50% duty cycle compared to AM, so transistors be they Mosfet or BJT's get a chance too cool down,Am never fully switches off so it doesn't cool as quickly,and running 20w PEP of AM into a KL203p is pushing it too its limits. That's why they fried them.

Incidentally I own two KL203p's so I think I know what I'm talking about, and I don't need any dumbass tech to fuck my radios or amps up,I repair other peoples gear, I've never had to repair any of my amps or radios in 35 years so maybe just maybe I know more about Amplitude Modulation than you do, after all its how I started on cb before it was legal in the UK on a President AR7 and before I realised SSB was far superior.

Next time you have a local mong running 3w swinging 20w pep through a KL203 get it on a spectrum analyser, will frighten the shite out you. Then you might grasp the basic fundamentals of Amplitude Modulation ;)
 
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Well I know Jazz has not had time to reply.......but I guess from all the PM's and positive pm's I have gotten all I can say is THANK YOU............. Nuff said. maybe they do stuff different in the UK. Any way thanks and take care.
 
So I finally decided on the amp I'm getting and I'm ready to order it. Just had a few questions first...

I plan to just stick my KL 203P under the seat. Does anyone know how long the power cord is on this amp? I am hoping it is long enough to run it straight to the battery. What all will I need to do this in addition to ordering the amp?
if the cord isn't long enough can I run the power to the fuse panel like I did my radio?

I already have a 3ft jumper coax cable that i bought for my swr meter that i will be using to hook the radio to the amp.

thanks, please give me suggestions on what to buy with my amp, like if i will need extra wiring, cable, etc.
I would not run the power cable from the amp to the fuse box..If possible try to run the ground wire close to the amp..Keeping the ground wire short is a good.The positive cable should go strait to the battery with a good fuse.Depending on how powerful the amp is wire gauge is important to....I have a 100 watt RCI 2970 in the jeep and i used 8 gauge wire for both positive and negative and bought some nice inline fuse holders on Amazon..I fused both cables..Kinda overkill on the ground but for a couple of xtra bucks its worth it...
 
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I don't know if the kl 203 is like this but I just figured out my Gray 200 base amp does not like to be over driven with modulation I never had a problem with my 140 gtl that I ran as a base for years but this 2000 changed every thing I have to shut my Silver eagle almost off to use the amp .:oops:
 
I would not run the power cable from the amp to the fuse box..If possible try to run the ground wire close to the amp..Keeping the ground wire short is a good.The positive cable should go strait to the battery with a good fuse.Depending on how powerful the amp is wire gauge is important to....I have a 100 watt RCI 2970 in the jeep and i used 8 gauge wire for both positive and negative and bought some nice inline fuse holders on Amazon..I fused both cables..Kinda overkill on the ground but for a couple of xtra bucks its worth it...
yup what i do too.
 
Well I know Jazz has not had time to reply.......but I guess from all the PM's and positive pm's I have gotten all I can say is THANK YOU............. Nuff said. maybe they do stuff different in the UK. Any way thanks and take care.

Glad to hear you've had so many pm's of support,pity they ain't got the gonads to do it on an open forum, but I'm sure it makes you feel justified in your claims, but then Antron / Solarcon sell many many Antron A99's and those people think they are good antennas, so delusion is rife in cb world.

Nuff said, I don't think so !!!

You claim 1w swinging 8 - 14 which is between double and 3.5 times the Carrier / P.E.P 4:1 ratio that gives 100% modulation (the perfect modulation for a clean AM signal). Your suggesting a chronically overmodulated signal full of harmonics being amplified by a non linear amplifier is a good idea, it has little if any filtering too by the way.

For a 1w input ideal P.E.P would be 4w P.E.P

I suggest 2w Carrier swinging to 8w P.E.P a perfect input for that amp and you tell me I'm wrong, I bet you a spectrum analyser won't tell me I'm wrong.

You suggest we do it differently in the UK, I do anyway, I can't speak for everyone as Ancient Modulation is barely if ever used here on CB, but I started on a President AR7 back in 78, you may know it, it's a FCC certified radio, and a damn good one at that, my next radio was a 120 Ch Cobra 148 GTL DX,pb010ab followed days later by an export version Stalker 1X, you will probably have seen that in the states too, in 40 AM/SSB guise, we got 80 AM/FM/SSB.

So right away I've started on 3 first class radios, all with AM, All Uniden made, which we used regular up till nov 2nd 1981 when our Govt in its infinite wisdom decided to legalise 27.60125 - 27.99125, on FM or more accurately Phase Modulation.

I also used the 148 on UKFM as it slides easily to the -3.75 Khz offset our government chose as well as still using it on AM for a couple more years and SSB till I got busted with it in 83, basically I was a daft kid of 16 and was overdriving the amplifier with it and causing allsorts of interference, which brought the wolf to the door and me seeking how to prevent it happening again.

I've had many radios since, all export Uniden or Ranger clone Sideband radios with AM. With an unmeasureable amount of Amplifiers, too many for my memory to recall.


you also claim the same P.E.P figures for SSB.


30 years later, almost 31 and your trying to convince me 1w carrier/dead key, call it what you want. swinging 8-14w P.E.P is a better setup than a 2w carrier swinging 8w P.E.P signal

Its no secret 100% modulation is the cleanest and best signal to amplify for a clean output and its a well known fact a 4:1 carrier ratio to P.E.P is whats required to achieve that without distortion/harmonics. I'm sure by now Freecell would have a sore neck from nodding, cause despite his people handling he was a very smart guy. I'm sure a few others will be too and those that don't agree about what I'm about to type, don't pm me bullshit, say it out here in the open, I don't bite, much.

Now we'll get to the crunch, and do some figures:

Positive Modulation % = SQ RT of P.E.P - SQ RT of CARRIER in Watts / SQ RT OF CARRIER in Watts X 100 :

Lets start with an easy one 4w P.E.P and 1W Carrier

4W P.E.P (sq rt is 2w) 2w - 1w (1w is sq rt of 1w carrier) = 1W / 1W = 1X 100 = 100% MODULATION, simples.


now we'll do it my way and both your minimum and extreme, I'll round up to keep it tidy ;)

my 8W P.E.P and 2w carrier = sq rt 8w P.E.P = 2.82w - sq rt of 2w = 1.41 = 1.41w/ 1.41w = 1 x 100 = 100% modulation.


lets try your best case scenario, cause your worst is frightening,

8w P.E.P and 1w Carrier already established both of these sq rt's in above 2 examples so i'll leave all that out:

2.82w - 1w = 1.82w/1w = 1.82 x 100 or 182% modulation, that's your best case scenario going through an amp with no filtering of any significance.


now the worst case, dearie me: that would be 14w P.E.P and 1w carrier, in your words not mine:

SQ RT of 14w P.E.P = 3.74w now we know SQ RT of 1 is 1 so here goes :

3.74w - 1w = 2.74w/1w carrier = 2.74 x 100 = 274% modulation going through an amp that ain't the cleanest to start with.

now we come to SSB, according to manufacturer, is fitted with a 12 amp fuse, so its safe to say with headroom draws about 10 amp at full belt, 13.8v at 10 amp gives a dc input of 138w, allowing for an optimistic 70% efficiency (thats where your heat goes) your looking at 138 x 70% = 96.6w, even if it was 100% efficient, which it ain't or it wouldn't heat up your looking at 138w P.E.P maximum.

I reckon this amp has about 10db gain with those 4 transistors biased the way they are., so when your pals are hitting 20w input the amp can't sustain 200w output and fries.


your friend/s with 3w swinging 20w are actually putting less overmodulation / distortion through than you are, whats blowing their amps is too much drive, yours ain't blown yet but it will be spewing shite all over the place and soon will blow at that level of abuse, thats if you don't get a knock at the door from the FCC first for causing mayhem all over the spectrum.


your friend/s overmodulation level is 20w P.E.P and 3W carrier,

sq rt of 20w P.E.P is 4.47, sq rt of 3w carrier is 1.73w so

4.47w - 1.73w = 2.74w / 1.73w = 1.58 x 100 = 158% overmodulation, another splatter box.


Feel free to get your pm buddies to check my figures, and bare this in mind, no matter what power meter you use be it bird,lp100,dosy or any other, it can't differentiate power on the fundamental frequency to power outside it. Only tool that will do that is a spectrum analyser which will break up exactly where that power is going. I can tell you this much without looking at a spectrum analyser at 182% modulation and over it ain't all going on the fundamental frequency.

now I've had time to answer you:
NUFF SAID !!!!

P.S. we don't have that problem using FM/PM as its not amplitude modulated, but don't mean some of us don't know AM swing is bullshit and when amplified, filthy.

73 Jazz
 
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