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I just got my bullet proof 1 amp hooked up and may have a problem. I have a hr-2510 and a Shakesspear big stick antenna. I use this on 10 meters between 28.300 and 28.500. Without the amp my swr's are 1.2 to about 1.4. With the amp they increase to about 1.6 to 1.8. Also the power seems to fluctuate a little bit maybe 5 to 10 watts and this makes the swr's change a small amount about .1 or .2 Is this a problem with the amp or ? The amp has 2 2879's and all the info I have found is they had 1446's I think. I am wondering if some one has been messing around inside the amp. It does not appear it has been worked on but you never know. This amp looks well built and all the info I have seen they are a good amplifier. I have a 30 amp power supply running the amp and a 20 amp for the radio so I have plenty of juice. The 30 is a switching supply that I read good reviews on a few ham sites that say it is clean for radio use. I have it set low at about 12.5 volts out.
Terry

they made 2 pill amps with both 1446's and 2879's

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are you checking swr and power with the meter after the amp and only coax between the meter and the antenna ?

Yes I have the swr power meter after the amp. I did notice that on the low setting my power out is more stable. I wonder if the supply is having issues at the medium setting? I will probably never use anything but the medium setting and figured 30 amps would hold this just fine. I turned up the supply voltage to about 13 volts and it made no difference. I was running it lower at about 12.5 volts.

how much pep power are you getting from the amp ?
what power supply are you using ?
most power supplies are rated at their peak amperage , not continuous .

The power supply is a mega watt switching supply. It is continuess at 30 and surge to 33. I have read good reviews about it on ham sites. The PEP I have seen at medium power is about 100 watts maybe a little less. My 2510 is putting out about 20 to 25 watts on ssb is what I usually talk on.

Looking at that web site they show the bullet proof 3 had the 2879's and the bullet proof one has the 1446. This says bullet proof one on the front plate, maybe they put the wrong front cover on or used what they had.

For an amp that potentially puts out ~350 watts; you are a little shy of the amps requirements from your power supply. It is always a fair plan to assure more amperage available from the power supply than the amp will need.

I would guess that if you are fully driving the amp input properly, it should do 275 and need about 35 amps. If you push the amp fairly hard; then 40 amps may become necessary. A rule of thumb, is to have a supply that has some 'head room' of 5-10 amps more than the amp will draw. Reason? So that you don't over-tax it and have a failure. It is also true that when the supply is taxed to the maximum, you will also have a voltage drop as well, which I'm sure you don't want/need either.

Just some thoughts . . .

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2879s are rated by the manufacturer at 100 watt pep . with the 13.8 vehicle voltage they can do a little bit more . since even doubling power has a trivial effect pushing them beyond that is pointless ....... unless how far a meter swings is more important than signal clarity and increasing the potential of bleeding into nearby electronics is your goal .

the swr change isn't worth worrying about , the antenna tuning hasn't changed . but , you could try a different jumper that might make the meter happy by read lower . the pills still have double the clean power available than the 100 watts pep you're currently getting . try the amp on high and see what your pep power is ....... if you want a little more power . do you have your mic gain turned all the way down when checking the vswr ? if not there may be some small amount f sound coming through slightly modulating your signal and the slight increase in power from it is causing the swr fluctuation .

btw , the 2510 you have is not the higher powered 100 watt model is it ?