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Carl Built

amplifier maximum carrier output is 25w per transistor (2879's). 25w -30w pep is all that you should need to get the 350w - 400w pep out of the amp. beyond that is just device saturation and splatter. if this doesn't get you squared away then im afraid an amplifier and its proper operation is to advanced for you at this point.
 
Attached are the datasheets for the Toshiba 2SC2879 and the HG2SC2879. As you can see by comparing the 2 datasheets, HG's sheet is almost a carbon copy of the Toshiba as far as Maximum ratings and Electrical characteristics. There is additional data on the Toshiba datasheet("Input power") that is not "copied" onto the HG datasheet. Look at the charts on page 2 of the Toshiba datasheet.

Granted the HG datasheet is not for the HG2SC2879C but the lack of complete information makes me suspect. :unsure:

73
David
 

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I may have another dodgy connection somewhere. I am occasionally having the amp seemingly lock on after I've un-keyed but only at the high position. It pretty much pegs the S-meter until I shut the amp off. I'll start tracing through this next. It seems like half the patch cables I have purchased from purportedly qualified vendors are actually crap.

Between the mice and squirrels and chipmunks and rabbits and deer and possum and skunks and foxes and owls and hawks and woodpeckers and wild turkeys and feral cats and the odd escaped cow or horse or pig and even a rare black bear, there are many suspects when random wiring problems arise.
 
sounds like your amp is going in to oscillations.

be sure to turn the amp and power supply off when this happens, as it can feedback much in the way a guitar amp does when the guitar is too close to it.
however instead of a loud sound you eventually get smoke.

this could be because of a tuning issue, too much input power, or a particularly bad length of cable between the radio and amp, but to me that still says tuning issue.

many times these amps are tuned on a dummy load by the builder and that doesn't really always relate to real world operating conditions.
LC
 
I have a two pill 2879C box that I got recently from a local builder, and it's been biased too.

From the label on the back of the amp that you posted. 100 watt carrier is what my builder said to run it at. He also said the amp can handle every bit of power from my stock Quad 6. He did say keep SSB to 400 watts or under.

With my stock Quad 6 on AM, 400 to 450 watts true peak out with a 100 watt carrier. My dead key is 5.5 to 6 watts.
 
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I don't like paying for gasoline but, if you wanna ride a big horse, you gotta buy a lot of hay. Nothing's free. Watts equal heat, heat needs fans, unless your pills were designed to be cooled some other way.
It's why tubes are fun. Glass is usually infrared convection.
Yes but, the amp can have the fan it needs without all the noise. Why listen to a bunch of noise if you don't have to?
 
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I may have another dodgy connection somewhere. I am occasionally having the amp seemingly lock on after I've un-keyed but only at the high position. It pretty much pegs the S-meter until I shut the amp off. I'll start tracing through this next. It seems like half the patch cables I have purchased from purportedly qualified vendors are actually crap.

Between the mice and squirrels and chipmunks and rabbits and deer and possum and skunks and foxes and owls and hawks and woodpeckers and wild turkeys and feral cats and the odd escaped cow or horse or pig and even a rare black bear, there are many suspects when random wiring problems arise.
I wonder what Carl has in it for the output tune? Might want to give him a call, maybe there is a simple solution.
 
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I do still have everything grounded and bonded after the exercise I went through a few months ago. The only thing I did was replace the KL503HD with the new amp. Nothing is soldered or spliced.

The amp works fine with the Lincoln at 3 watt dead key and 30 watts PEP. I have not tried it any higher than that yet with this radio.

However, it's a different story with the Q5N2 at about 3 watt dead key and 30 watts PEP. I am using the stock mic and tried varying modulation levels. It seems to work well on AM on both low and hi settings and SSB low setting. SSB high is a different story.

This video shows what it sounds like after I have released the PTT button when the amp is on high. It stays like this until I turn the amp off at the 5 second mark. While the voice is (was) crystal clear with the amp on low, when on high it's probably even worse than the KL503HD was. Even more troubling is that now even with the amp off, SSB audio is somewhat crackly.

Now that I am an "expert" solderer (cough), I popped open the Anytone case and had a look-see. There are four IRF520s and I happened to still have some new Vishay ones left from the Digikey purchase I made a few months ago. It only took me about 20 minutes to neatly replace all four. I then re-assembled and re-tested the Anytone with and without the amp. The radio dropped about 5 watts output but the AM voice quality was still fine. SSB without the amp was still crackly and with the amp on high I had the same problem as before.

Carl's said they tested the amp before shipping and it was working properly. I think I have to agree with him because it works fine with the Lincoln. He also said that there should be no problem running the Anytone Q5N2 with this amp. But for me, it just does not work properly with the Anytone on SSB with the same dead key and PEP as the Lincoln and the amp on high. It just really annoys me that I don't know nearly enough to get down to the root cause of the issue between the two of them. Something with the power supply? Or because the radio and amp are both connected to the same 120 amp PSU? I have tried multiple patch cables and configurations but no improvement. I re-checked bonding and grounding and all looks well. SWR is good.

And now I get to figure out what testing the Anytone with the Carl Built did to the SSB audio quality. I assume it had something to do with the feedback generated when the amp was on high and did not unlatch.

This is definitely a mix of frustrating/fascinating.
 
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I had a nice surprise arrive in today's mail.

I do need to extend the power and ground wires before I can hook it up to my PSU though. It looks like the existing wire is 8 AWG. I already have a bunch of 6 AWG THHN lying around from other projects so I may just use it. I think it should be fine. I just need to determine the best way to splice them since I know I don't have any appropriate connectors/terminals on hand. Of course I'd have the same decision if I pick up some 8 AWG too.

Do any of you folks splice in an inline fuse holder when connecting your amp to your PSU? A 50 amp one right by the PSU might be a good insurance policy.

I just hope the SSB is as clear as folks say it will be when running an appropriate amount of drive and modulation.

View attachment 62709View attachment 62710
I have the 400hd. I replaced my wires with #4 awg and installed twist welding connectors. I would not splice the wires. Install some Anderson power connectors. A At-5555n ii may be a little too hot for this amp. the recommended power input for this amp is 40 watts peak power.
You bought a Class C amp for SSB? Is this a good idea?

JD
His amp is class B biased for SSB use.
 

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