• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

FatBoy 6 Pill

I think that magnum PI has the same question - maybe?

But your question depends on the spec sheet for this device. A watt - even if it is peak and momentary - is still carrying all of the energy of that same watt. So it matters. If watts are a measure of force/power; then if it is given all of its input peak watts - then hasn't it reached its requirement for full saturation for that device? I think the answer to that is 'yes', since we also see the corresponding peak output watt value of that same device that the specs give it.
 
Last edited:
I would hook it up as is. Unless you have long winded QSOs with it, it should be fine. To make sure, install a volt meter at the amplifier power input. When the voltage starts going down then get off the key. This will let you know to either upgrade the charging or reduce the drive or both.
 
Just logged in for a sec at work. By all means, hijack away! Will read and respond (if I can add anything) later.
Thanks to all for all the information.
 
  • Like
Reactions: Shadetree Mechanic
Hi everybody. I have been reading this site for years and have learned much. Never felt compelled to say anything till now. Which by the way I learned from here and also the old mauldroppers. And proved it myself in the real world.

No one will be able to hear the difference between 500 and 800 watts. Or 400 for that matter. The extra watts might give you q little more distance depending on location but not much. It may also allow you to get above the noise floor if your right at it as heard from the receiving side. It may also let you walk on the guy next to you if they are at 500. But thats it. It wont make you louder and the distance gain isn't worth the effort either which leaves you with walking on people.

If that is your bag then yes you will need to run a bigger alt and second battery. See here http://www.k0bg.com/alternator.html

However if you want to talk clean and talk your local county or so just fine and skip all day. Just run it around 400 to 500 with a 100 watt deadly. You will sound better...and your equipment will last a lot longer. It will put you around the 65 amp real world draw where you where looking for.

I have a similar setup with a stryker 655 driving. I run it through a sirio 5000 in the center of my roof. I drive it to 100 deadkey...swing to 400-450. Perfect. It will do 600 but so what?

What I have learned more than anything else is that pushing for every last watt is detrimental to your sound and your equipments longevity.

You need to essentially quadruple the watts to make a difference on the receiving end. 500 or 800 no one will notice accept you will be cleaner and clearer. And run cooler with less voltage drop. The more your voltage drops the more IMD qnd common mode current you will get in the mobile which will cause further problems.
http://www.k0bg.com/common.html


My motto...from what I have learned here and applied to tbe real world is...over buy and under drive...

Thanks in advance for everyone's patience...and...hopefully...acceptance...73's.
I'm out.
 
Hi everybody. I have been reading this site for years and have learned much. Never felt compelled to say anything till now. Which by the way I learned from here and also the old mauldroppers. And proved it myself in the real world.

No one will be able to hear the difference between 500 and 800 watts. Or 400 for that matter. The extra watts might give you q little more distance depending on location but not much. It may also allow you to get above the noise floor if your right at it as heard from the receiving side. It may also let you walk on the guy next to you if they are at 500. But thats it. It wont make you louder and the distance gain isn't worth the effort either which leaves you with walking on people.

If that is your bag then yes you will need to run a bigger alt and second battery. See here http://www.k0bg.com/alternator.html

However if you want to talk clean and talk your local county or so just fine and skip all day. Just run it around 400 to 500 with a 100 watt deadly. You will sound better...and your equipment will last a lot longer. It will put you around the 65 amp real world draw where you where looking for.

I have a similar setup with a stryker 655 driving. I run it through a sirio 5000 in the center of my roof. I drive it to 100 deadkey...swing to 400-450. Perfect. It will do 600 but so what?

What I have learned more than anything else is that pushing for every last watt is detrimental to your sound and your equipments longevity.

You need to essentially quadruple the watts to make a difference on the receiving end. 500 or 800 no one will notice accept you will be cleaner and clearer. And run cooler with less voltage drop. The more your voltage drops the more IMD qnd common mode current you will get in the mobile which will cause further problems.
http://www.k0bg.com/common.html


My motto...from what I have learned here and applied to tbe real world is...over buy and under drive...

Thanks in advance for everyone's patience...and...hopefully...acceptance...73's.
I'm out.

Nice first post! And I think this is exactly what the man of few words who did the bench test was trying to convey to me. He probably thought I knew more than I did, I was just glad to be there really. Reading this thread makes me really apprehensive about installing the amp in my 2016 Ram 1500 5.7L 4x4 (to clarify my vehicle). Overbuy and underdrive, sort of what Shadetree is saying. I don't wan't to blow doors across the globe rambling "audio audio audio" for hours. I want to be heard with authority in my commute and possibly skip once and a while. But if it means upgrading alternator and extra battery to do so, I would rather go the base station route. I also like the idea of the voltmeter at the amp.

Knowing my vehicle and my intentions, could I install this system and not worry about frying electrical components without upgrading?
 
Well, you have the type of amp that accepts pretty much what most people would call, a high drive radio.

You can take a bone stock Cobra 29 and throw it on there at it'll run that thing all day...put a JP36 mod in there (The Cobra 29 I mean), might not be the best option - because brining the dead key down too low, you'll have trouble with that amp...

One of the things that using an amp can help you with is -signal, as in power-out but they can't do SSB, nor are they Class AB biasing, this thing is strictly Class C straight out of a Motorola handbook and test circuit. And if you set the carrier too low, you won't sound well on the other end of their speakers - kinda embarrassing in a way...

So that limits you to essentially two modes (three if you include CW) AM, and FM modes - no sideband.

Has you friend set up the radio to help you key it?

Now I had been mentioning the amp draw - thanks for filling us in on the Dodges' profile, it should handle that amp on a regular-use basis - just fine.

Now before someone steps in here and says "oh you'll get this and if you do this you'll get this type of wattage out" - please be careful with that - it' is subjective to say the least.

One of the main crux's of this thread is the efficiency effects on wattage. Well, yes, there's that and then there's the idealized system and then - when you put this all together, the crash and hitting of the brakes when you deal with Real World.

Now, the above has to be said because I want you to accept and approach this whole install in a simple yet straightforward matter - don't make this hard on yourself.

You've got ideas, by all means use them - do your best with them, when you have a hiccup or two, we're here to help. But you have to step out of your box because that amp is going to introduce you to things you never knew would occur and do exist as "the devil is in the details"

Like power wire routing...

IT may be easier to Bolt that amp and ground all your radio and antenna equipment around and at that amp - and let the battery cables' ground return from the frame, to handle the rest of the feeding and care of that system.

Why does that matter, because the simpler you make the install - the easier it is to maintain and untangle it from the rest of the mess of that emission headache they call ECM ...

The Ground cable back to the battery will need to be checked, cleaned up - replaced with larger cable or supplement a cable to return to the battery's Negative side, from the frame is always a good option - as long as you know you are using a Negative Ground ignition.

Because if you try to route ground directly back to the battery - the frame has it's own return and noise abatement filtering going on at the fuel pump, ECM, spark plugs Charging system and all electrical lighting windows and support stuff you never knew you'd have in a vehicle. You can upset the ground returns "stability" by making ground at those other systems - force its way back to the battery thru the grounding system the Amp uses - the moment you key the amp - it can push power thru and into ground and force a loop back to the alternator and it's built in regulator thru the return at the engine block and possibly do a misfire alert setting the Check Engine light on, on your dash board and depending on the severity of that error - force it into Limp In mode.

A simple fix, but why go thru that headache - again, keep it simple.
 
Last edited:
  • Like
Reactions: 5 X 5 and Robb
Thanks again for all replies. A high drive amp... Pretty sure the Magnum 257HP fits that bill. I have a few other CB's but nothing as powerful or versatile, and I also enjoy 10M from time to time.

The tech did put the Magnum before the FatBoy on the bench to a dummy load. He seemed more impressed with the radio than the amp but knew the amp well.

I like the idea of connecting the radio power to the amp. The radio will be close to the amp and the antenna mount wont be too far either. I guess everything will be less than ideal, but I can relocate anything if problems arise.

Plan is to put amp behind passenger seat. It fits perfect there, easy to reach the power switch, plenty of ventilation and I think the battery is on that side. If I hear you right, I will run the positive from the amp directly to the battery. I will run the negative from the amp to a frame ground nearby, possibly the seat bolt. I will then run a supplemental ground cable from the battery to the frame.

The radio power will just connect to the amp power terminals. I can also hook the Fluke up at the amp terminals to keep an eye on the voltage drop for a while. It sucks but for now the antenna will be mounted behind the cab on the passenger side with a post hole mount. I have a Bakflip bed cover so even that might be tight.

Negative Ground Ignition? I have no idea...

Other than that I would like a little stadium echo from time to time. I have a 4 pin DM-1000 Superstar Tornado power mic somewhere. Do you think this adapter would make the mic work with the Magnum? https://www.wearecb.com/c4pdf6.html

This mic ( https://www.wearecb.com/magnum-257-echo-microphone.html ) is hard to find these days but I think there is still a place that will wire it for 6 pin, but I would rather take the cheap adapter route if possible.

It's going to be a long, hot, busy holiday weekend so not sure when I will start hooking stuff up. So many projects...
 
amps x voltage = watts

If you multiply the amount of amps in a power supply and its voltage, the result is wattage.
So plug in 50 amps times 13.8 volts and it comes to 690 watts.

But we must consider that transistors aren't 100% efficient when they use amperage to make RF power. In this case, it think it is only like 65% of the available power can be converted into RF power output.

SO, if we multiply 690 watts times 65%, we get 448 usable RF watts output from a 50 amp source.
Which is NOT enough for full 6 pill output.

Since you can expect 750 clean watts from the amp if it is driven with no more than 60 watts from your radio (10w per pill = 60w input power) amd it has enough amperage available to it, you will need almost 100 amps to feed the amp to get the full 750 watts out of it.

That is the math behind the physics that makes it work.
Just saying.

Your 257HP radio will require about 10-15 amps - in addition.

That math is good if we were looking at AM carrier, FM or ssb modulated by a single tone.

Take a radio that is tuned properly for 100% modulated AM and connect a pep watt meter. Watch the amp meter on the power supply as you speak i to the microphone. The pep meter will swing to 4 times the carrier and the amp meter will just wiggle a bit. What just happened?

Same for a radio that swings backwards on a average reading meter but swings a pep meter forward. Amp draw from the power supply actually decreases with modulation.

Whenever you want to measure efficiency or use ohms law you have to use an average reading watt meter or a steady unmodulated carrier. You cannot not base it off of pep while talking into the mic on AM.

The straight 6 pill is 3 two pill sections put together. The input is divided by a 3 port splitter, amplified by all 6 transistors then combined with a 3 port combiner. No built in driver.
 
Negative Ground Ignition...

Disconnect the NEGATIVE of the battery - use an ohmmeter set to 1Xohms.

Test leads - Black (Negative) to Battery CABLE - not post - other to bolt head on frame.

Meter will, or should, show a short - full deflection all the way over - some meters have a beep to confirm it's continuity - you should hear it.

If you DON'T show full deflection - recheck test leads TO Touch EACH OTHER - it may need to be "zeroed" so do that then perform the test again.

IF it shows deflection, near dead short, but not all the way - there may be a separate relay grounding unit - this is what I was warning you about - some vehicles, to keep the battery from draining use a sense lead to the ECM that detects a battery drain and "kills all power" to the fusebox. one of two ways, their returns are tied to a relay terminal that is powered by the ECM - or the ECM can Kill all power thru the main buss relay - you "reset it" by fiddling with the device you left on, or the doors, a simple open and close will reset the relay. Put the key in the ignition or if you have keyless - the "Start" button resets it too...

IF this feature was enabled and working - you amp could damage the sense circuit for this function to work.

To bypass? Well if you get nearly full deflection - re-test by CABLE to test leads (either one) to ENGINE BLOCK - and if that shows continuity GOOD - you have NEGATIVE GROUND IGNITION.

To "defeat" the sense - you bypass it, locate the Engine Block hoist loop or tang, it's a bracket bolted to the main part of the Engine block, part of the Factory assembly process - you can use one of those bolts to make a Braided strap to FRAME Ground from the Block to the FRAME.

The Sense wire TIES all it's returns to itself for the SENSE - so to reduce it's "false trigger" you have to bypass it and make the ENGINE BLOCK and FRAME ground the same - leave the Battery Cable to itself you'll see why in a moment - read on...

Make a braided strap - even automotive store can offer these - they are lug to braid to lug and use the bolts on the Frame and Bolts of the BLOCK - to tie grounds together. You can make your own but you need good quality Copper Braid SOLDERED to the LUGs' and not many people have access to this...so a trip to the store may help you here...

Install one of your straps - LUG to BLOCK, and LUG to Frame of vehicle - a good place on the Engine would be close to the torque axis of the engine mounts (the balance point of that engine hoist bracket) so whether if it is Traverse mounted (side to side) or front to back engine (spark plugs go from front to back of the compartment firewall) mount the Lug's closest to the engines CENTERLINE - along the axis of the plugs. This prevents the engine from tearing or breaking the straps when under heavy torque loads - keep some slack in your braid for this movement.

Where to mount the Lug side, that again is a measurement point but any bolt that is used to bolt parts of your frame together - and if you look for, say the wiring harness by it, it may have a bolt it uses to tie off it's ground wires too - mount your other LUG there - it may need to be a game of well it won't stretch this way, try here approach to make it all work and have enough slack in it to accommodate engine torque movement - but eventually you'll find a spot that you can tie the BLOCK to FRAME....

Now, Take your other Lug strap and tie off that Lug on the FRAME - to BATTERY NEGATIVE post terminal. chaining it this way, allows the ALTERNATOR and it's built in REGULATOR to sense the amps keying load and react accordingly to the vehicles electrical system thru it's output post - your GROUNDING thru the FRAME INTO THE ENGINE BLOCK AND ALTERNATOR CASE provides the opposite side. This is important for proper sense for Regulation to occur and keep the battery from draining into your amp - the Alternator on these things is capable of 100 amps easily for todays battery and starting systems - so the REGULATOR - to sense the load before it hits the battery - needs to be made equal as much as possible to the voltage drop losses the battery will see (Your cables provide the low-ohmic path for this) - this way the Regulator will not let the battery drain - it will put in the needed charge to the electrical system to keep the system at 13.8 to 14.4 Volts .

You can bring the POSITIVE power cable from the amp and its buss terminals to the battery POSITIVE post straight, directly to, as you can, solder well the lug, and use an in-line fuse to keep the truck and you and the shop you get your truck fixed at, happy...STRAIGHT TO POSITIVE battery post.

Just remember that the NEGATIVE Battery CABLE should be dead short or close to Ground of Engine AND Frame - for again I must advise you that any vehicle that has the self-off feature to prevent battery drain - will have to be bypassed (The method above is what I've been using and it's not a bypass, just adding BLOCK to FRAME, and FRAME to Battery for the amps sake) to prevent a MIL light ON problem indication in your dash. You can leave the "Battery cable fusible link (that's their secret - that voltage drop loss) alone" because they will have a grounding relay for their INTERNAL ECM/CAM wiring carp when the engine starts and is on running. Plus these straps and cables can be unbolted if warranty issues come up - like their required visit to the dealership stuff for warranty service - this is the easier way to install and remove your work so they don't get pissed.

Enjoy your holiday...
 
  • Like
Reactions: 5 X 5
That math is good if we were looking at AM carrier, FM or ssb modulated by a single tone.

Take a radio that is tuned properly for 100% modulated AM and connect a pep watt meter. Watch the amp meter on the power supply as you speak i to the microphone. The pep meter will swing to 4 times the carrier and the amp meter will just wiggle a bit. What just happened?

Same for a radio that swings backwards on a average reading meter but swings a pep meter forward. Amp draw from the power supply actually decreases with modulation.


Whenever you want to measure efficiency or use ohms law you have to use an average reading watt meter or a steady unmodulated carrier. You cannot not base it off of pep while talking into the mic on AM.

The straight 6 pill is 3 two pill sections put together. The input is divided by a 3 port splitter, amplified by all 6 transistors then combined with a 3 port combiner. No built in driver.
Good point. Had a chance to think about this. Not sure with my conclusions, so I'd thought I run it by you.

We see on a scope a 100% modulated AM signal. As modulation is applied the carrier energy looks like it is collapsing the carrier as it approaches the negative peak. So in a sense, that energy is already stored in the carrier envelope and that energy is used to modulate the signal. Is this what you are referring to?

Never had the chance to watch current draw with amps, since I so seldom have to look at them on the bench. This amp is no candidate for SSB since it has a C class biasing scheme. To be even more honest, to be used on AM it really should have B biasing, since C biasing is spec'd and meant for FM use. Too bad there isn't anyone around Magnum PI's neck of the woods that can add the diode bias trick - or even a proper AB bias circuit.
 
Last edited:
  • Like
Reactions: 5 X 5
Good point. Had a chance to think about this. Not sure with my conclusions, so I'd thought I run it by you.

We see on a scope a 100% modulated AM signal. As modulation is applied the carrier energy looks like it is collapsing as it approaches the negative peak. So in a sense, that energy is already stored in the carrier envelope and that energy is used to modulate the signal. Is this what you are referring to?

Never had the chance to watch current draw with amps, since I so seldom have to look at them on the bench. This amp is no candidate for SSB since it has a C class biasing scheme. To be even more honest, to be used on AM it really should have B biasing, since C biasing is spec'd and meant for FM use. Too bad there isn't anyone around Magnum PI's neck of the woods that can add the diode bias trick - or even a proper AB bias circuit.

Tell me more about the benefit of this "trick" or the "bias circuit". I rate myself 7/10 in soldering ability. If it's not too complicated and actually beneficial, I have the equipment...

For SSB I can just flick off the amp and use the 257HP. The 257HP has always been great for highway use, but since I stumbled across this FatBoy, I just can't pass up taking things to the next level. Looking at grounding straps now...
 
Tell me more about the benefit of this "trick" or the "bias circuit". I rate myself 7/10 in soldering ability. If it's not too complicated and actually beneficial, I have the equipment...

For SSB I can just flick off the amp and use the 257HP. The 257HP has always been great for highway use, but since I stumbled across this FatBoy, I just can't pass up taking things to the next level. Looking at grounding straps now...
Ehhh, have never done it myself. But there are a few threads on this forum somewhere that gives details. Something about isolating the input xformer from the board's ground plane and strapping a 1n4007(?) with one side of it ground down a little and then strapped across the pills and uses the pill's heat to change the resistance. Couple of disc caps are needed too. Can't remember the details. bob85 (forum member) knows how it is done, and I'm sure a few other members may know as well.
 
Last edited:
  • Like
Reactions: 5 X 5
Sounds complicated. I'm satisfied with AM only. As far as I can remember, I have really only used SSB to respond to a couple 10M contests I happened to catch going on. Would be cool though and something to keep in mind for later on down the road. Thanks for making me aware.
 
Good point. Had a chance to think about this. Not sure with my conclusions, so I'd thought I run it by you.

We see on a scope a 100% modulated AM signal. As modulation is applied the carrier energy looks like it is collapsing the carrier as it approaches the negative peak. So in a sense, that energy is already stored in the carrier envelope and that energy is used to modulate the signal. Is this what you are referring to?

Never had the chance to watch current draw with amps, since I so seldom have to look at them on the bench. This amp is no candidate for SSB since it has a C class biasing scheme. To be even more honest, to be used on AM it really should have B biasing, since C biasing is spec'd and meant for FM use. Too bad there isn't anyone around Magnum PI's neck of the woods that can add the diode bias trick - or even a proper AB bias circuit.

I don't have a formal RF education so sometimes it's hard to find the words. You've got the right idea though. The negative and positive peaks are occurring in such a short period of time the power supply only has to keep up with the average.

Class C isn't the proper way but you can get away with it on AM. More IMD (splatter) comes from the amp being overdriven than the biasing. To run clean I bias them heavy (200ma per pill) and run 60pep output per 2879. I use a regulated bias and lots of airflow across the heat sink. The linearity is good and it works well on any mode.

If you run any amp hard it's going to splatter. If you want something to hammer on AM save your money and keep it class C. The transistors run cooler too. If someone runs a 2879 past 60 watts pep they don't care as much about clean as they pretend to. If youre a ssb guy have it biased and run the thing at about half throttle. Ssb sounds bad enough as it is.:)
 

dxChat
Help Users
  • No one is chatting at the moment.
  • @ Wildcat27:
    Hello I have a old school 2950 receives great on all modes and transmits great on AM but no transmit on SSB. Does anyone have any idea?
  • @ ButtFuzz:
    Good evening from Sunny Salem! What’s shaking?
  • dxBot:
    63Sprint has left the room.
  • dxBot:
    kennyjames 0151 has left the room.