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Night_owl
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Username: Night_owl

Post Number: 2
Registered: 4-2005
Posted on Friday, May 27, 2005 - 3:40 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I'm having a hard time finding any info on a Grey 300 amp. Can someone tell me what kind of output they are capable of and how many watts I should be putting into it? It will be hooked to a Galaxy 55v so I have the variable RF power to adjust it with.
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Couchpotatoe
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Username: Couchpotatoe

Post Number: 2
Registered: 6-2005
Posted on Monday, June 13, 2005 - 8:21 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

night owl
depends on a few things. i suppose it has toshiba 2sc2879's... with 1.5" collector transformers wrapped 4T, .5" base transformers wrapped 4T, capacitor on the collector to ground around 100-300pf, base-base loading of 350-500pf,
and a collector-collector loading around 1200pf+...now with this (2)transistor will do about 400 watts with 60-75w drive (4) will do about 800 with 140-160w of drive. these measurements are on p.e.p. you'd hate to see what they'll do r.m.s.
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 934
Registered: 7-2004
Posted on Monday, June 13, 2005 - 8:45 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i smell SMOKE!
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Night_owl
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Username: Night_owl

Post Number: 4
Registered: 4-2005
Posted on Tuesday, June 14, 2005 - 1:30 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

It does have 2 toshiba 2sc2879's. As far as the rest goes if you'll point me in the right direction I'll let you know. I;m driving it 10w swing 18w. Amp keys 90w swing 130-150w. By the way the Galaxy has not been peaked and tuned,only had the AM power turned up a little. If they work here are a couple of pics.

amp
amp pics
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Couchpotatoe
Junior Member
Username: Couchpotatoe

Post Number: 13
Registered: 6-2005
Posted on Tuesday, June 14, 2005 - 11:30 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I WOULD RECOMMEND 2-3 WATTS DEADKEY AND SWING ABOUT 30-35 IN TO IT. WILL PROBABLY DO ABOUT 300-350W. BUT THERE ARE WAYS TO GET MORE(A LITTLE BIT)OUT OF IT. BASICALLY DEALING WITH THE TRANSFORMERS ON THE BASE AND COLLECTOR. A BIGGER COLLECTOR T.F. SQUEEZES A LITTLE MORE POWER OUT OF THE 40AMPS RMS 50AMPS PEAK THAT IT CAN DRAW.
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Couchpotatoe
Junior Member
Username: Couchpotatoe

Post Number: 14
Registered: 6-2005
Posted on Tuesday, June 14, 2005 - 11:37 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I FOR GOT TO ASK ARE YOU GOING BY BIRD WATTS OR P.E.P WATTS. FOR A 1000 WATTS P.E.P., A BIRD METER WILL SHOW YOU ~70.7% OF P.E.P OR ABOUT 710 WATTS. REMEMBER DEADKEY IS DEADKEY. 2W D.K.ON BIRD IS THE SAME AS 2W D.K. ON PEP, ITS THE AMOUNT OF SWING THEY MEASURE.
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Night_owl
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Username: Night_owl

Post Number: 4
Registered: 4-2005
Posted on Tuesday, June 14, 2005 - 1:21 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I'm taking my readings from a Dosey meter. The guy I bought it off of said he pushed it with a 25w (dosey) deadkey Galaxy. That's why I have my key set so high. To adjust my swing I need to turn up the modulation inside radio, right? I have the radio variable power adjusted so full low is 2w swing 5w. At this setting the amp does 17w key and swings 80w. I know I really need to get it tech tuned but I can't find 1 less than 150 miles from me and I don't trust shipping it. I'm a person to person kind of guy.
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 937
Registered: 7-2004
Posted on Wednesday, June 15, 2005 - 5:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

the SMOKE is getting thicker.

your gray 300 with 2 x 2879 should key in the 80 watt range & swing 240 or so, with a dead key of 4 watts or less.
the only galaxy getting 25 watts dead key is 1 of the big boys like a 95t-maybe 1 x 2290 also. why would anybody even attempt to drive a 2 x 2879 with a 2 x 2290??? the 100 watt increase from 1 amp to the other is hardly worth the time to unscrew the coax. no mass produced 2 pill is gonna take 160 watts of pep, especially when the design is for 250 watts out by way of 20 watts pep input. & even if that gray is up to the task of 6 or 7 watts dead key input, & that driver is able to get 160 watts swing out of it, the 1:23 key to swing ratio is gonna sound OOGEY at best.
if you wanna use a commercially made amp, that's because you haven't the desire or possibly even know-how to mod or build for MAX. no offense intended-there is nothing wrong with that. use it as the manufacturer recommends & you'll gets loads of enjoyment out of it. overdrive the heck out of it & it'll end up sitting in the junk heap. if you want a 2 x 2879 that keys 120 & swings 400, go custom. mass produced just gets SMOKE at those outputs.

couchpotatoe, reread your posts, 'this (2)transistor will do about 400 watts with 60-75w drive' and 'I WOULD RECOMMEND 2-3 WATTS DEADKEY AND SWING ABOUT 30-35 IN TO IT. WILL PROBABLY DO ABOUT 300-350W.' which is it?? the custom YOU build may do that, but that gray ain't.
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Couchpotatoe
Junior Member
Username: Couchpotatoe

Post Number: 27
Registered: 6-2005
Posted on Wednesday, June 15, 2005 - 7:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i see where i got side-tracked, i was still thinking on my specs. but to answer,which is it, commercial made 2pills i own get a dead key of about 2-3w and swing in the range 30w,but it depends on transistors. now this is my explaination for low d.k. and tall swing.
i have yet to come across a (2)sd1446 palomar 200 that would hold up to a 4 watt d.k. the specs on the sd1446 transistor calls for 70w output w/ 7 in. 2 makes 140 in bird/200pep. now back to the subject, with a perfectly mod. signal, 4d.k.-6swing will not make that amp do 140w. a palomar 400 i know to take 5w d.k., and gets hot, but 7.5w swing will not get 280w. now how is it that my tube amplifiers work right and these transistorized things are really s***!! there are things even i don't know. but i do know this, whatever amp you use, set your d.k. on your radio to where the amp sets best, swing only what it takes to get it to full potential. for another example, my galaxy350 (2)2sc2879's calls for 5w d.k. and swing up to 20. it wont handle the 5w d.k. 1w d.k. 10w out, 2w d.k. 25w out, and at 5w d.k. i wont say because it was insane. i'd like to see -one- palomar "whatever" do like its supposed to. we have to do whatever it takes to make this junk run right! even at the expense of pollution because the manufacturer couldn't build but a polished turd!
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Night_owl
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Username: Night_owl

Post Number: 5
Registered: 4-2005
Posted on Thursday, June 16, 2005 - 1:15 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I ended up setting the dk at 3w swings 6w. This puts a 25w dk and 85w swing through the amp. So far I have been getting good reports like this so thats what I'll run for now. And to Patzerozero I do have the desire to run better custom equipment but for know I don't have the knowledge or funds to jump that far into the hobby. I am very satisfied with the amp for the uses I have for it as of now. But I am getting pretty addicted to radio, just ask my wife. I would like to thank both of your input and I have learned some about the various output potentials of different setups. Learning is what its all about.
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 944
Registered: 7-2004
Posted on Friday, June 17, 2005 - 4:38 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

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Bigbob
Senior Member
Username: Bigbob

Post Number: 1983
Registered: 12-2001
Posted on Saturday, June 18, 2005 - 7:08 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Well,my boomer 400(4-sd1446's)WILL TAKE A 10 WATT dead key for 90 out and 360 for swing,on ssb this same will do 560,crisp clear and barely above room temp,I must have gotten the very best one that was ever produced by whoever made it,bought it from our benefactor,3 years ago.Bigbob
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 953
Registered: 7-2004
Posted on Saturday, June 18, 2005 - 11:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

as long as it gets out, whatever meter says can be used as a reference point to show trouble. if it works-THEN IT'S GOOD!
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Bigbob
Senior Member
Username: Bigbob

Post Number: 1991
Registered: 12-2001
Posted on Sunday, June 19, 2005 - 7:12 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

That grey has awful small transformers,not much bigger than the ones in my little grey 50+,but I love its matching network.Bigbob

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