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More stuff: First off, let me post a couple things that I should have posted right off the bat since I can't edit the OP anymore. The complete kit for the EB63a amplifier and all 6 filters can be purchased quite reasonably from Communication Concepts, the amp here and the filters here. This is...

The datasheet power ratings for the MRF455 are peak ratings, so PEP. The MRF455 isn't specified for SSB usage (they're specified as class C transistors, but work fine in class AB applications) but datasheet maximum power ratings are always peak ratings unless labeled otherwise.

You and Bob85 and others helped me with figuring this stuff out initially through your posts, so for that I'll always be grateful. I'm no stranger to electronics, but until now I've worked exclusively with digital and AF analog stuff. RF is a whole different ballgame, even more so the higher you...

@Shockwave: Actually that's just an anomaly of the photo. The ends of the resistors connect to the little choke coils you can see there, the other end of which is soldered to the base of each transistor. The connection at the choke is actually about 1/4" off the board surface, but it looks like...

Update! Things are coming along nicely.. I've added feedback to the amplifier, as the EB63 has none by design. This consists of a .01uF capacitor, 47 ohm 5W resistor and a 20uH vk200 choke on each transistor. This is untested, but should work.. I've got filters finished for 160-40m and 10m...

Since I'm a big believer in customizing amps, I still feel that it would be a very simple job to add feedback and spruce up the grounding a little.. Nothing wrong with buying a better amp, but you can very likely get your skeleton much closer to up to snuff with very little effort. At the end...

From that picture it looks like the only ground connection is the one connected to the negative power wire at the bottom so-239.. :unsure:

I can't take credit for the pic, I just googled it up and added the feedback components in paint. I needed an easy way to illustrate where to add feedback. It's such a simple thing to add really.. Those guys are the reason I got turned on to this site, which may be a good or bad thing depending...

That all makes perfect sense.. I didn't realize there was no feedback. The EB63 I'm working on right now doesn't have feedback by design, but I'm adding a .01uF ceramic cap on each side each in series with a 50 ohm 5W resistor and a VK200 inductor, the value of which I'll be experimenting with...

Not long ago I read up a little on class E stuff.. very fascinating. A class E amp is in my long term plans to build.. after I'm done with my current projects.

Harris DX-50: 50kW Solid-state PWM AM broadcast transmitter. Crazy awesome stuff.. does not glow in the dark though ;). The PWM method of achieving AM is very fascinating to me. As I understand it, the DX-50 has a whole bunch of amplifier modules inside, a couple hundred I believe, all of...

hmm.. that seems odd to me as well. Typically when harmonics are measurable, they are lowest when the amp is being driven lightly, and highest when the amp is being driven hardest. They certainly can cause higher SWR readings with certain meters, but it's wierd that you are reading these higher...

I must be confused AudioShockwav, as it sounds to me like he's describing the exact opposite effect, with the swr being highest at the lowest power output, and lower with more power. If that's actually the case, then I doubt it's harmonic content.. More power will never "drown out" harmonic...

The SWR at the antenna is 3:1 or higher unless the amp is kicking out a good amount of juice? Or are you reading the SWR at the amp input?

Looks sweet, I love the DIY stuff.. If I may share my thoughts, I'd like to say that since your antenna is horizontally polarized, you'd be paying a premium in received signal strength to the vast majority of stations you'll talk to since the majority of CBers seem to have vertical antennas...

Birthdays seem to come faster and faster to me as well, so it's not just you. Happy Birthday!! They say 39 is the new 29 ;)

Agreed.. people take GAMES way too seriously. Just look at that poor guy that nearly was beaten to death in California. Then you've got leaders of respected halls of education who would ditch the whole curriculum just as long as their sports programs are intact. Shit's a total joke if you ask...

^Thanks for all the replies so far! PA629, you've got it right on the money thanks! I'll be having a good look at that site..

I've got a couple of amplifier projects coming up that will require enclosures. My worst-case plan is to get a heatsink, have it drilled, and find some sort of enclosure for it. There are other amplifier enthusiasts and builders here, so in the interest of simplicity I'm hoping that someone...

May as well add this to my entries: http://www.worldwidedx.com/amplifiers/107942-construction-140w-pep-eb63-amplifier-low-pass-filters.html I didn't see any requirement that the project be complete, this one is a work in progress, so let me know if this is not a good project for this contest.