D&A Maverick Dual Power

[420Snowman]

Sorry ,i typed that wrong and should have worded that better. thank you for pointing that out. I will attempt to remove foot from mouth now.

now this all depends on who you ask LOL as we all know. we must consider a few things

That the average under-informed operator that is looking for that "swing" above all else is going to try to break the laws of physics,( The modern thinking of the so called "peak and tweak" is HYPE for the most part!

In reality weather it be tube or transistor finals The MAX ratings are the MAX ratings PERIOD!) there are methods of pushing the limit a little bit but it always comes at some cost. see 6LQ6 tube specs [Please login or register to view this link]

Like it or not the 4:1 ratio (carrier output to modulated peak output) stands firm as it relates to AM operation in class B or C. (there may be other methods that im ignorant of haveing to do with Class D or E operation.)

200 W carrier is way too much but im sure that there are those that will try and run it that way having used up all the head room and pushed the amp to saturation at that point and throwing out harmonics and spurious all over to get perception of modulation.

A maximum around 250W maybe 300W modulated PEAK of in AM operation is what you can expect and not have it get too sloppy . that would be 50-80 W carrier MAX.

Being that all meters, setups and applications are going to read differently for a multitude of reasons and that many less precise watt meters are of the type that show people what they want to see as power output rather than what really is some operators are going to claim they are getting out as much as 700 to 1000 watts . If you overdrive and over modulate the **Censored** out of any amp sure you might see your meter register an 800 but it still really putting out the spec ratings of the finals on the fundamental frequency and the rest of the power that your meter is showing you is combined harmonics on other frequencies,reflected power and what i call "splatter watts"! and that is really not the actual true power output.

The 6LQ6 tube has been used in many designs in the past due to its abundance and dirt cheap price of decades ago as well as it can be pushed pretty hard and still hold up for a while. However for it to be clean and sound good one must realize that it is closer to a 50 watt tube not a 200 watt tube for RF applications. It's intended purpose is not really a transmitting tube but it will work and work well even cleanly if respected for what it is.

Bottom line The D&A Maverick is a 250 watt amp even IF the power supply was enough for a huge power like 800 watts the tubes simply cant do that! on AM

Now on SSB i have seen nearly 500 on high. In SSB you can often push a device to its edge with little or no problems because not only is the duty cycle much less than with AM but the way SSB works is a different sort of animal. Again every application and setup is going to behave differently so individual results will vary somewhat

It should be noted that these amp should not be driven with any radio that is modded for crazy swing! that is what get these amps a bad rep for splatter.
A tvi filter after the amp is a good idea as well.


If anyone can tell me where im wrong please explain because i dont know everything i just know what ive seen and proven. There are those engineers that can explain it better than i can im sure. Please do

I sold mine, it worked well for me but on upgrading to a steel tube. In glad this post has gone on a while because there is a lot if usefull info here, thank you for that!

Snowman
Sent from my Grim Reaper powered HTC.

[Ohio_359]

If anyone can tell me where im wrong please explain because i dont know everything i just know what ive seen and proven.

Nope, I'll buy that. The 200w carrier had me scared a little is all

[Radio1cb]

I still have my maverick but i only fire it up every now and then to work the caps and keep it working. I like ceramic/steel tubes too but the soft glow of glass tubes warms my soul. if you have an old D&A take care of her and she will never let you down like a nice grandmother.

[Night Crawler]

To operate the tubes in that amplifier within their ratings on AM the amplified unmodulated carrier from that amp should be around 100 watts with a peak envelope power output of around 400 watts on modulation peaks.

[str8stroke]

I still warm mine up every day! She has never let me down! Shes the oldest piece of gear I have and by far the most reliable! I can't imagine a day with out her! She likes a 2 watt dead key swinging 12 watts. When I treat her to that she is most happy!

[crazy_cooter]

It's so hard for me to become detatched from my amplifier!

[BigBambu]

Which tube amps (like the metal tube ones your all talking about) are better and which brands should I look for?

[str8stroke]

Hey Big, I am not sure if you already have heard or know this but:

MAKE SURE YOU GROUND THE AMP! Your mav should have a ground stud on the rear. This should be connected to a earth ground rod. If you notice your "wall plug" only has 2 prongs? If so, you need to hook up a safety ground! Just some cheap advice for you.

[BigBambu]

Does that have to be to the buildings main ground rod for the AC or can it be a seperate copper ground rod? Also, what awg ground wire should I use 10awg or thicker?

[str8stroke]

As with all grounds, the shorter the better. So..you have to determine that. Personally. I slid (using a water hose) a 8 foot ground rod from Lowes in the ground connected with solid #4 (i think that was the #) copper grounding wire. Strapped to the rod, then ran to a copper to a buss bar in my Man Cave. ALL my gear grounds there. I have been a witness to what non grounded gear can do to skin! I even go as far as to ground my Cobra 25! lol kinda over kill I know.

[crazy_cooter]

Ok, I need a logical explanation here.....I argue with other CB'ers constantly over this. Your coax has a shield, which in turn is a ground. The outer shell of your PL-259 has solid contact with the chassis of the amp, and your coax runs out of your amplifier, to your antenna, which is grounded to a metal tower....which is.... IN THE GROUND! How is running a seperate ground going to make the current ground from your coax shield any better? I grounded all my equipment for experimental purposes, and I noticed absolutely no change whatsoever. My SWR didnt change, my noise level is the same, and I didnt benefit anything from it. Can somebody explain how running a seperate ground from the chassis of an amp, or a radio is doing them any justice? To me personally, I think it's overkill unless someone can convince me otherwise. Sorry, not trying to sound like an idiot, but i hear about people grounding this, and grounding that.....it all doesnt add up! I even knew a guy who ran a ground from his antenna when it was mounted on a metal tower!!! Can you say, PARANOID??? LOL

[str8stroke]

Hey CC, great question. In most cases its not about a SWR issue on base stations. However, on old tube gear you may notice there is a "two prong" plug. If you see gear with this it likely lacks a safety ground. Which in turn can allow voltage to appear on the metal chassis of gear. This can be a very dangerous situation as you might expect. Most gear has a Ground Stud located on the rear. This may or may not be marked? That is where you would want to ground the gear.

As for the tower or push up pole, grounding is a must. But not just for static discharge & general safety. If you think about it, wouldn't you want as much voltage to discharge in the ground verse your gear or inside your home? The voltage will follow the path of least resistance. Hence the reason for shortest grounds. You may want to do some research on this topic just to be aware of all aspects of proper grounding and your local electrical codes. I am not even gonna go into Home Owners insurance policy issues! Thats another topic for another day. In some cases its just cheap insurance. No Pun intended!

Hope that helps clear up my view for you. Thanks! See ya! Btw, does the Browning eagle have the 2 prong plug? I have never played with one.

[crazy_cooter]

Yes Browning has a 2 prong plug. My amplifier has a 3 prong. I follow your theory now, and it does make sense. The other question in my head though about having an antenna grounded when it is mounted to a metal tower already in the ground, doesnt make too much sense to me. I really cant see it doing anything different than what the tower already is. On the other hand, grounding a tube type rig that only has a 2 prong electrical cord makes perfect sense. Static does need to discharge from it at some point in time, and an external ground would serve a purpose in that case. I've felt a slight poke from amps in the past if I would lay my wrist on the edge of the case.

[str8stroke]

On my pushup pole for example: Its a 40 foot pole which has is 3 feet in the ground which is sunk into concrete. The concrete is not really a good conductor. However a 8 foot ground rod which is normally wrapped in copper is. Most towers are secured by concrete as well. On a 4 leg tower you would have one rod per leg. Those would in turn be connected together, effectively making one large ground. Does that help you understand it a little better. There is alot of different ways to skin the cat. But what I listed above is sorta the norm.

[crazy_cooter]

I understand what you are saying, but it doesnt answer my question. I really didnt have concrete in mind through my thought process, as most towers around here are just sunk into the dirt and braced to a building. Therefore the tower has no need for a ground. I'm not saying your wrong though, because you cannot achieve a ground through concrete I don't believe.

[str8stroke]

Ok, if the towers are braced to a structure then you would want to have insulators keeping it isolated. Same reason you are supposed to use Isolators on your guy wires when attaching to say your home. You wouldn't want any discharges to come inside your home. Also keep in mind a metal or fiberglass antenna can build up large amounts of static which if not discharged properly can be transfered to anyone touching the tower or possibly the support structure. And a 22 foot long antenna can pack quite a static punch! And you don't even have to touch it, just get close enough for Mr. Arc to getcha! lol I am not sure that covers your question completely but I tried.

[Night Crawler]

I argue with other CB'ers constantly over this. Your coax has a shield, which in turn is a ground. The outer shell of your PL-259 has solid contact with the chassis of the amp, and your coax runs out of your amplifier, to your antenna, which is grounded to a metal tower....which is.... IN THE GROUND! How is running a seperate ground going to make the current ground from your coax shield any better?

The tower is a conductor and is well grounded the coax line should be grounded at the top of the tower and at the base of the tower.

During a lightning strike the tower and coax will share the strike energy if the coax line is not grounded more energy could tranverse the coax toward you equipment then is conducted to ground by the tower.

[Ohio_359]

My feedline and coax is completely isolated from my tower. I have a dedicated ground coming from the service panel where I have a bus bar that everything is connected to.

[crazy_cooter]

I would have to say yes.....I think you guys may have nailed it this time for me. Pretty much what it boils down to is static discharge needs somewhere to go, and it will more or less take the shortest path to ground. Makes sense to me. As far as lightning protection, I really wasnt referring to lightning strikes. Don't get me wrong, I am well aware that grounding is never a bad idea. I am glad you guys cleared it up for me.

[str8stroke]

Glad we could help you CC. Thats what good forums like this are for. Everyone can learn something sometime! I know I have learned alot here too. Its the old saying, Several brains are better than one!

[jtrouter]

Now i understand that i am posting to a post that is over 10 years old, However for people that are searching about the D&A Mavrick 250. This amp is a 250 watt amp. No more no less! I keep seeing youtube videos with people saying that they get 700 watts 800 watts ETC. i call BULLJUNK. In truth on AM these AMPS in GOOD shape with good tubes should be dead keying 50 or so watts and then "swing" to 200/250 MAX. On sideband They might peak around 400 watts, but average 325 watts. This is real world numbers! Sure you can overdrive them for a short amount of time harder but you will trash out your tubes and other parts of this amp. These SHOULD be driven with a STOCK radio or a stock wattage call it 4 or 5 watts MAX. Do not drive it with a swing kit radio. If you drive it right it will talk forever on a set of new tubes and treat you well. But do not belive the stories of 700 watts or more or think your amp is not doing what it should when you ONLY get 200watts.

[MDYoungblood]

Now i understand that i am posting to a post that is over 10 years old, However for people that are searching about the D&A Mavrick 250. This amp is a 250 watt amp. No more no less! I keep seeing youtube videos with people saying that they get 700 watts 800 watts ETC. i call BULLJUNK. In truth on AM these AMPS in GOOD shape with good tubes should be dead keying 50 or so watts and then "swing" to 200/250 MAX. On sideband They might peak around 400 watts, but average 325 watts. This is real world numbers! Sure you can overdrive them for a short amount of time harder but you will trash out your tubes and other parts of this amp. These SHOULD be driven with a STOCK radio or a stock wattage call it 4 or 5 watts MAX. Do not drive it with a swing kit radio. If you drive it right it will talk forever on a set of new tubes and treat you well. But do not belive the stories of 700 watts or more or think your amp is not doing what it should when you ONLY get 200watts.

Good post jtrouter, glad you brought it back. There are quite a few old D&A amps out there, with tubes going for high dollars it is best not to overdrive them to save the tubes. And remember, they were built back in the day, no such thing as a high drive radio!

3’s

Greg