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--- In ham_amplifiers@..., "Robert B. Bonner"
<rbonner@...> wrote:

Yeah we had to straighten out a few of the guys on AMPS today.



A touch of the professor's wisdom.

### anybody who doesn't know what a 3x3 is... well... they should
go straight to their ARRL hand book.... where they still won't
figure it out.

### Dunno where the 11m term "pill" came from. Saw that a few
yrs back.... "192 pill amp" ... what did they do.... build a
heatsink the size of a 4 x 8 sheet of plywood.... and then run the
entire mess on 18V ?? What's the IMD on ssb, on these things ??

### Using a linear amplier on AM seems kind of silly to me.....
since the cxr power is only gonna be 1/5 of the pep output. You
woulod have to pulse tune it to full pep output [tube amp].... then,
with an unmodulated cxr... adj the cxr for 1/4 to 1/5 the pep
output.

### what exactly goes on in one of these shoot outs ?? I heard
each vehicle has an assigend freq... and they each send a 10 sec
dead cxr..... with the referee 20 miles away... and his spectrum A.

## I also heard some times there is as much as $25 K in prize
money. Who's bank rolling all this prize money ...Eimac ?

Later.... Jim VE7RF

BOB DD

Yeah I seriously thought of getting into that game myself at one time.
What a way to make a living.

I was going to take a suburban and remove the 454 and place a diesel 480v
3ph generation unit in it under the hood and back into the cockpit. Use a
100HP electric motor to move the BURBAN and fill the rest of the back with
big tube power.

Wear a lead lined space suit and go for the gusto.

But then I got a huge dose of reality and that was that. It felt good to
know I had a plan.

BOB DD

On Fri, 12 Jan 2007 17:23:18 -0800, pentalab <jim.thomson@...> wrote:

--- In ham_amplifiers@..., "Robert B. Bonner"
<rbonner@...> wrote:

Yeah we had to straighten out a few of the guys on AMPS today.



A touch of the professor's wisdom.

### anybody who doesn't know what a 3x3 is... well... they should
go straight to their ARRL hand book.... where they still won't
figure it out.

### Dunno where the 11m term "pill" came from. Saw that a few
yrs back.... "192 pill amp" ... what did they do.... build a
heatsink the size of a 4 x 8 sheet of plywood.... and then run the
entire mess on 18V ?? What's the IMD on ssb, on these things ??

Pill: MRF455 looks like a small pill of aspirin.

192 devices are built as 3 64 device amplifiers, and then they combine them.

### Using a linear amplier on AM seems kind of silly to me.....

Using a non linear amplifier produces distortion, unless your high level modulating it.

Although it is common to run class b/c (whichever you choose to call it) grounded base when running high Vcc. This mode does create a LOT more junk on the band.....

Another 'trick' if you will the competition guys do is overdrive the living hell out of their amps. Swinging wildly as a switch, they can get quite a bit more output.... But C'mon, how clean is it, and how much MORE real output power is it, when you're driving a 2879 with 80 watts PEP, and running it at 23 volts? Sure, it's making the Bird move wildly to the right (if you have a peak kit), but....

They don't really rate the distortion output of these amps. Most "builders" (they don't call themselves tech's anymore, becauses too many of the real tech's out there put them in their place and showed them they can't design or fix themselves out of a wet paper box... Most of the "builders" on 11 meters actually came from club DaveMade, and through bad drug deals, branched out on their own.) just copy DaveMade's design, and that's nothing more than a different mix of ferrite and Motorola App Notes clobbered together on a board that's dremel tooled to etch it... Or, more often than that, they just hot glue small strips of pc board material.

These amps work, and work quite well at what they are designed to do, but to ask about SSB use is ludicrous.

since the cxr power is only gonna be 1/5 of the pep output. You
woulod have to pulse tune it to full pep output [tube amp].... then,
with an unmodulated cxr... adj the cxr for 1/4 to 1/5 the pep
output.

No, actually they rate their stuff at full bore, carrier power.

I actually watched a box I helped build get tuned up. They turn the carrier control up on the radio, and tune every stage for max suds. Just make the meter move farther to the right, and that's alright.

Of course, since the waveform is nothing more than a squarewave when it hits the pair of 4CX15000's, they can take being driven by 15,000 watts. The duty cycle is a lot less than 100 percent, overall.

It's a 10 second key, usually.

### what exactly goes on in one of these shoot outs ?? I heard
each vehicle has an assigend freq... and they each send a 10 sec
dead cxr..... with the referee 20 miles away... and his spectrum A.

It's RF Drag Racing. Two guys line up in a field, and they have a guy standing up in the middle. He raises his hands, you hit your motor and fire down.... When he drops his hands, it's all over.... It is taped at the "watergate" station, and run in a typical elimination manner. Each time, a winner is brought up, usually over the air. That night, the watergate (tape) is played for all to hear at the keydown.

## I also heard some times there is as much as $25 K in prize
money. Who's bank rolling all this prize money ...Eimac ?

You would be amazed at how much money is flashed around. It breaks down as such.

1. Some of it is drug money. It IS a predominately black sport, but honestly, I find more drug infested riff raff on the white end of the racial scale. However, honestly, not much of it is drug based, and most of that comes from back east, mostly northeastern.
2. Mostly it's successful business owners. The person that I learned to work on large amps from (he used a 4CX10,000 in 1986) owned a roofing company. The mobile I spoke of earlier is owned by a trucking company owner. One of the builders of these large amps owns a construction company, and he gets the hotrod motors from his brother who is a NHRA drag racer. So, it isn't a bunch of lames. One of the guys who is building biased, class AB boxes is a famous entertainer.... 5 years ago, he was building non-biased grounded base crap, but over the last 5 years discovered the proper 4/1 carrier pep relationship beats raw needleswing.

Later.... Jim VE7RF

No problem. I had / have videos of these guys in action. That dual 10,000 box spoken up above actually destroyed the AC power adapter on a camcorder when we where taping it.

People talk of contesters having severe RF...... The biggest station on I know of on 11 meters right now is running.... Well, he has a 50Kw slug in his line section, and it can move pretty much as far to the right as he wants it to. That is fed into an 89 foot long 9 element longboom yagi. His protoge on the opposite side of the US has a 90 foot beam with over 35 thousand watts of plate dissipation on his final.... Dedicated 400A 3 phase input.

11 meter shootouts, now THAT'S extreme contesting.

Have fun.


--Toll_Free


(I have a few pictures of some of these beasts, a dual 15,000 box in various stages of assembly. The 3CX3000 is now the driver of choice on 11 meters... Those are feeding our single 20,000 boxes. Contesting has no limits, when people aren't risking their license. I think it's gotten way out of hand, but hey, thats the way the needle swings, right?)

BOB DD

--



*Ratings are for transistors, tubes have guidelines*

On Fri, 12 Jan 2007 17:38:46 -0800, Robert B. Bonner <rbonner@...> wrote:

Yeah I seriously thought of getting into that game myself at one time.
What a way to make a living.

I was going to take a suburban and remove the 454 and place a diesel 480v
3ph generation unit in it under the hood and back into the cockpit. Use a
100HP electric motor to move the BURBAN and fill the rest of the back with
big tube power.

There is a gentleman in Florida with a big block in the back of a van, moving I believe is 7 or 8 alternators.

His ERP (out of the phased array) is close to quarter million watts.

Another friend of mine in San Diego has a pair of 15,000s being driven by a Harris 3-1000Z military box. This is mobile, with a 5 element yagi on top, direct fed 50 ohm W2DU balun/choke fed. This is mounted in a Freightliner purpose built. A 150Kw Onan is mounted to the rear, where your 5th wheel would normally be.


Then their is Weed in Florida who ran a pair of 10,000s into a 6 element on a Texas Towers mobile tower setup.

Wear a lead lined space suit and go for the gusto.

But then I got a huge dose of reality and that was that. It felt good to
know I had a plan.

And it's also good to know that you don't want to compete with idiocy.

One person is using a military induction power unit I've heard. BIG numbers, coming out of that unit.

--Toll_Free

ORIGINAL MESSAGE:

On Sat, 13 Jan 2007 01:23:18 -0000, "pentalab" <jim.thomson@...>
wrote:

### Dunno where the 11m term "pill" came from.

------------ REPLY FOLLOWS ------------

"Transistor" has more syllables than are allowed on 11 meters. :-)

Bill, W6WRT