My new Brimstone Amp

[70cst]

I thought I would go outside the box and so I bought a Brimstone amp. I am going to match this up to my Galaxy 99. From most threads...it sounds like it is much better to use an external amp with your radio. Why Brimstone...I just wanted something different.

Specs: 2x 2SC2879 Transistors Capable of 400-525 watts of peak power as measured on a Bird 43P @ 15 Vdc with 40-125 modulation input. Dead key input should be from 1-15 watts. 2x 2” 4500 rpm fans ensure maximum cooling. Also has a ‘low-medium-high” power switch. Approximate HxWxD = 3”x4”x5”

 

[Grogan]

How do they get so many watts out of 2 ea 2879's

 

[Robb]

I have never been impressed with big numbers from class C amp builders. Output devices are only capable of so much power output at a given feed voltage before they naturally distort regardless of who builds the amp. Distortion isn't a welcome thing. It can be a source of bleed-over to others. It robs power from the power supply. It is a cause of premature device failure due to the excessive heat/due to the square wave it is generating.

Two 2SC2879's fed @ 13.8v should provide no more 275 watts with relatively low distortion. Anything more than that is fluff. Read the spec sheets of these same devices sometime if you don't believe me.

Preacherman built. Nice. He usually does fine radio work from what I have personally seen. Sure hope he gets on to build the AB biased amps soon - though. This C class biased stuff sure is 'old hat' and just plain nasty on AM! Not to mention - virtually useless on SSB. Unless you like it sounding grungy. Just a natural consequence of class C bias operation - BTW . . .

 

[70cst]

I have never been impressed with big numbers from class C amp builders. Output devices are only capable of so much power output at a given feed voltage before they naturally distort regardless of who builds the amp. Distortion isn't a welcome thing. It can be a source of bleed-over to others. It robs power from the power supply. It is a cause of premature device failure due to the excessive heat/due to the square wave it is generating.

Two 2SC2879's fed @ 13.8v should provide no more 275 watts with relatively low distortion. Anything more than that is fluff. Read the spec sheets of these same devices sometime if you don't believe me.

Preacherman built. Nice. He usually does fine radio work from what I have personally seen. Sure hope he gets on to build the AB biased amps soon - though. This C class biased stuff sure is 'old hat' and just plain nasty on AM! Not to mention - virtually useless on SSB. Unless you like it sounding grungy. Just a natural consequence of class C bias operation - BTW . . .

Thanks for the info...
Makes sense.

I never run the power past about 1/2 to 2/3rds.

 

[BOOTY MONSTER]

i hope one of those fans is blowing in and one out , other wise its not circulating air . the computer fans i've used blow air out of the side without the label ... and both fan labels are on the inside in the pic . one could be wired backwards to correct that though .

 

[psycho]

How do they get so many watts out of 2 ea 2879's

You can if you drive the snot out of them.

 

[fodendaf]

i hope one of those fans is blowing in and one out , other wise its not circulating air . the computer fans i've used blow air out of the side without the label ... and both fan labels are on the inside in the pic . one could be wired backwards to correct that though .

there is probably a vent hole under the heatsink with both fans pulling either in or out. if there is no vent hole the air will never circulate through the heatsink as there is too much space in the case.

 

[n0zna]

125 wtt transistor getting 300 or so,ya right...if it does its dirty as hell...hope they are not in my area,we have enough splatter boxs now...73

 

[n0zna]

dont like class c stuff...ab1 will not piss off the neighbors on the radio and tv and stereos,or ems,fire and police...they are doing that in my area now...

 

[70cst]

dont like class c stuff...ab1 will not piss off the neighbors on the radio and tv and stereos,or ems,fire and police...they are doing that in my area now...

Just out of curiosity ...

Whom are the better ab1 amp builders...

Thanks

 

[BOOTY MONSTER]

messenger , cobra , galaxy and a very few palomars . the bullet proofs were nice too .

 

[project]

I just stopped by preachermans shop 2 days ago and while I found him to be a very nice man, he will never put a screwdriver in anything i own.

 

[Ratfink]

I just stopped by preachermans shop 2 days ago and while I found him to be a very nice man, he will never put a screwdriver in anything i own.

Why does he use gold plated screwdrivers?

 

[Mudfoot]

Do tell.

 

[n0zna]

the better ones are,palomar,tx star,boomer,d and a,amertron,henry,tempo,yaesu...tentec.mbl amp the best is the al500 by amertron...