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Thinking CarlBuilt 400HD for AT6666 combo

Had a decal made while I was waiting for the amp to arrive.

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Looks great, glad the deal worked out for you. Its no fun having something shipped that gets stuck in limbo. After the new ness wears off maybe you could pop the top and take a few pictures? I am real interested to see what he used for input and output matching capacitors, as well as the transformer capacitors. I have been thinking about getting his 8 pill amp maybe this summer.
 
Only downside this far is fan level. Kinda loud. Great air flow. Moved to top shelf. PS is on bottom. I'll take the nice easy swing to 500-525 without hollering in stride though.

The AM has me miffed abit. With my low drive radio (Ranger 296) which does a 1w dk and swings to 6 1/2w on AM I get 30w dk and swings to 300w.

With my AT6666 and 3w dk I get like a rediculous 250w dk and swings to 500w from that. Wondering if his non-bias side uses a CAP to boost.

I run 99% SSB so if I need to go AM I'll just hit the switch and use the Ranger 296.

I'll have to wait for him to open to ask him about the AM thing. Make sure I'm not nuts.

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I'm happy the delivery service finally connected with you!

You probably know my thoughts on the drive levels....you're doing it right! If you ran 100W pep into that amp no one on the other end would know the difference.

Not sure what to think about the 1 vs 3 watts dead key. I hadn't seen a CB type linear with a semblance of linearity yet. I'm not terrible surprised that 3 watts gets you 250 out...With Toshibas I'd run just like that. Haven't run any of my new amps with Chinese transistors on AM.
 
(n)Ok. Here's the radio AM DK on lowest setting. Like 2w. Swings to like 14w pep.

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Amp on DK (like 260-270w). Swings to like 450-500 pep.

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Reading online about some competition HD amps can take upto 200w pep (which is this ones spec). Some actually due start with a high DK and go up from that. Supposed to be 10w dk max from radio or 200w dk from the amp. So that's my concern as I'm over that by like 60-70w. (n)

I sent Carl a message to ask him. Thinking that's how this one is done up.

Also noted my PowerMax 100 still has not had the fan kick on at all ever. Which has me concerned. And I noticed the Amp fan drops down abit when I key and talk. Sent Graham a note also about the PowerMax. Running it at 14.2 vdc. Radio is on the Megawatt 30/33

I'll run on SSB only till I hear back.
 
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It takes a while for the fan to kick into high on mine. You are probably ok, just need to talk more for it to kick on high.

just wish mine would kick on at all. Hasn't which I would think is odd. Also as noted before my voltage seems to drop and fluctuates according to my meter. Like 14.2 down to like 13.9 (which is the .2 in the manual) to 11.8, like it bounces.

Made sure like 50x that it's set to "fixed mode".
 
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Adjust your dead key on radio so you get 100w dead out of amp... 260-270 is to high and try and keep 4:1 ratio

the lowest the AT 6666 will go is the 2w as shown. (was turned down inside when I had it setup for me). Just can't figure out why I'm hitting such a high DK with amp on and only 2w dk. Even my old 4 pill Palomar I just sold didn't get that crazy high of a dk. Hence me scratching my head.
 
Ok. Here is my Ranger 296 numbers. 3/4-1w dk on AM swings to 5 1/2 pep.

88776B9B-B121-4922-B029-DD8565F31313.jpeg
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Gets a very tiny 20w dk with AMP on (meter on 200w) and swings to 350w (peak hold is on for this shot) (meter on 2000w)

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So at 5 1/2w I get 350w pep. Which kinda lines up with the 250 for 2w dk. (n):unsure:
 
I will probably try to adjust the AM low pot on the 6666 to knock it down abit. I don't see how 1w extra on dk can make a 10 fold increase on the Amp dk when on.

I did notice in Carl's videos his Cobra 29 has like 0 w dk and then swings to like 30w. So I'm guessing he has a swing kit. That may explain it. (n)

His site does say not more than 10w dk or 200w dk with amp on and not more than 200w pep in
 
The amp isn’t going to be linear (or at least I highly doubt it). I doubt you’ll find a 1:4 input level that equals 1:4 out.

The whole “swing kit” concept is built around this idea.

With old Toshiba amps I ran them all 1:2 carrier to peak. That carrier helped “drop the maul”...lol.

I don’t know what people do nowadays with Chinese transistors. Haven’t been into AM in forever.
 
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So I opened up the 6666. Lowered low power to like 3/4w. Lowered HI one also to like 15w. (Was at like 18w dk)

3/4 swung to like 4w with PEP hold on to get the pic.

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on low 3/4w I get like 175 dk on amp which is under his 200w dk mark. Just still think something is up with the AM "tune" side of amp. Also noticed the radio (not the Daiwa) is saying better SWR with higher AM dk. 6w dk is getting me 1.9:1 and with the 3/4w and amp on I get like 3.3:1. I do notice when I modulate the SWR on the radio drops a couple points.

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