Fatboy 150/300 watt amp

[cheetah 1]

A local guy is selling a Fatboy amp that according to him produces 150 watts on low power and 300 watts on high power. The only writing on the amp is "Fatboy Products". There are 2 switches on the font: one is an on/off switch and the other switches between low and high power. The back has 2 jacks, one for antenna and the other for radio. It has a 20 amp inline fuse in the power wire. I've searched the web with negative results, I can't find any information on them at all. Does anybody know anything about these? How old are they? Are they really rated for 150/300 watts?

[rosman6119]

It all depends on what type of transistors are in the amp so to answer your question yes it is possible to do 150/300 watts, it sounds like it may be a 2 pill amp by pill I mean transistor find out what kind are in the amp.

[1206FL]

Yes this is very possible, like said depending on the transistors used it will produce 300 watts. Is it clean @ 300 watts on a scope, most likely not, but then again, these are normally a class C CB amp for AM use. If you want to use one on SSB you would need to have some work done to get it to at least a class B if not AB biasing, and a delay and other things added as well. But then you won't see those same wattage readings after having this done.
The amp if it only has 2 switches, and On/Off and L/H power setting switch, I am going to go out on a limb here and say it's most likely your run of the mill Dave made clone 2 pill amp, class C splatter box! Nothing more, nothing less. If it has Toshiba 2879's and the price is right grab it as long as you see it produce the wattage numbers being claimed and can also look at the transistors (pills), to see what brand/type they are. You can always send the amp to a good amp tech and have it reworked for SSB use, or just to have a better amp, just as long as the transistors aren't burnt and they aren't new ones. Toshiba or keep moving!! JMHO. DEI transistors aren't bad, but if someone has been beating on the amp over driving it, I would be very careful before you buy!! The Toshiba transistors could take some major punishment and keep chugging along!! At and rate, hope the info helps.
The amp, like I stated, is most likely a class C CB amp. A clone of a Dave made amp. But not near the quality of an old school real deal Dave made amp either. At any rate, let us know if you get it and how you intend to use it. For AM or SSB, or both?? If AM only, grab it and a coupe of low pass filters. One for before the amp and one after the amp. This will help keep the signal cleaner at least!! Again, hope all this helps. Have a good one.

[MDYoungblood]

I would say it is one of the older creations, most newer versions have a variable knob instead of a toggle switch. Sounds like one of the 2 pill trucker specials, has two 2290's in it, the 300 watt claim (maybe if you volt it up) is just hot air, you will be lucky to get the 150 (13 to 14 volts). Take a pic of it and post it, your able to do that now. The earlier posts are right, no bias, C class amp.

3's

Greg

[PA629]

The 20 amp inline fuse makes me wonder......no way is that big enough for a 2 pill amp, at least not for very long.

[cheetah 1]

OK, I tried to download a couple of pictures but I get a message that says "file is too big, max allowed size is 100KiB". Anyways the "pills" that you refer, if I'm looking at the right things (they look like a "pill") have the markings:
0 ST
SD 1446
764F 0707
He wants $150 for it.

[MDYoungblood]

OK, I tried to download a couple of pictures but I get a message that says "file is too big, max allowed size is 100KiB".

Best to use [Please login or register to view this link] , it's free and easy to use. The image poster on the forum was the same but it has problems so it was disabled until a fix can be found.

[MDYoungblood]

Hmm, that is one of his older amps, how many "pills" are in it.

3's

Greg

[cheetah 1]

2 pills

-- Monday, 29 February 2016, 15:23 PM --

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Let me know if I did this right.

[tba02]

The 20 amp fuse is fine for a 2xsd1446 amplifier.

Sent from my SCH-I545 using Tapatalk

[jessejamesdallas]

That's a older Fatboy...But as long as it works, $150's not a bad price.

[cheetah 1]

I greatly appreciate all the feedback. Gotta say this is one of the best forums that I've ever been on as far as getting help/advice.

[Crusher]

Keep the dead key low. That case doesn't have a fan. It will heat up pretty quick

[cheetah 1]

I'm assuming the stock 4 watt dead key is what you're referring to when you say to keep it low?

[jessejamesdallas]

I'm assuming the stock 4 watt dead key is what you're referring to when you say to keep it low?

Get it down to about 2w and you'll be good to go.

[Deleted User 14541]

Put a watt meter behind the amp and make it key around 40 watts. Any other way is taking a shot in the dark. Put a fan on the heatsink if you can.

[PA629]

The 20 amp fuse is fine for a 2xsd1446 amplifier.

Sent from my SCH-I545 using Tapatalk

It's probably enough, but then a 2x1446 amp isn't a 150/300W amp as was initially claimed, that's what I was referencing with my previous statement.

[MDYoungblood]

The 20 amp fuse is fine for a 2xsd1446 amplifier.

Sent from my SCH-I545 using Tapatalk

It's probably enough, but then a 2x1446 amp isn't a 150/300W amp as was initially claimed, that's what I was referencing with my previous statement.

I would say it's at the minimum size too. 1446's will handle the 4w DK input but they are not a big swing wattage transistor, that is where you need to make the limit, the PEP. Very good pic of it's inside, most can't get close enough to see details. Everything looks good so it should work. That was one of the trucker amps like I said before, adding a fan would be nice but not a necessity.

3's

Greg

[Deleted User 14541]

Every amplifier using a pair of 1446 transistors (or anything else) is not the same as others. Deciding how much drive is acceptable by the spec sheet alone and not considering the rest of the circuit built around the transistors is still taking a shot on the dark.

[PA629]

Every amplifier using a pair of 1446 transistors (or anything else) is not the same as others. Deciding how much drive is acceptable by the spec sheet alone and not considering the rest of the circuit built around the transistors is still taking a shot on the dark.

True enough.