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Gee.. that sucks then.

New from Freescale, the MRFE6VP61K25H LDMOS RF power MOSFET is capable of 1250W CW power output @ 50VDC from 1.8-600MHz. My how far things have come.. MRFE6VP61K25H Product Summary Page I had heard a price of ~250 per unit.. not too shabby for better than a kW. EDIT: the device is actually a...

You're absolutely right, lousy wording on my part. What the meter sees has nothing to do with the radio technically, it's all about the feedline and the antenna. The radio just senses the mismatch, if there is one.

You might have better results using MOSFETs instead of BJTs, however I can't say exactly what that would entail in terms of modification. FETs require a different, but simpler, bias scheme.. normally a simple voltage divider will do the trick, but you'd need to bias in accordance with the...

A low SWR is never anything to worry about. The lower the better. As you can see in the plot above, the low point should ideally be in the middle of the band. Channel 20 is the middle of the Citizen's band. All is as it should be.

Pretty sad.. My experience was over a decade ago, and I used both the Wilson 1000 and the K40.. I LOVED the K40.. the Wilson was good too, but I really liked the K40 more.

I've never used the K30.. only the K40 (which, oddly enough, I hear very little about these days) which used to be pretty amazing.. I worked many different countries with a K40 and a stock Galaxy 88 in my ride. It just sounds to me like the K30 has a narrower bandwidth than most people would...

I absolutely agree.. the problem is that they are out there, like it or not, so one should always be sure they have their networks secure. And you're right, it is a worst-case scenario, but it has happened before and I'd hate to see it happen to anyone else.

^So you're nuts is what you're saying? Just recently a guy had his door kicked in and was arrested by the FBI because someone else outside of his house was using his open network to download child porn. Of course he was *eventually* freed, but do you really want to go through that kind of BS...

Hmm.. I see. -24db isn't too great, that's true. That's weird since IIRC they are pretty common in some HF rig's PAs, but I suppose in those cases pairs of them are being used to produce only 100W total.

^The 2sc2879 datasheet states 100W PEP max @ 12.5V 28MHz. Maybe you're thinking of the 2sc2290? Unless the datasheet figures are not taking IMD into account, but I can't remember seeing a power transistor datasheet with a published max output power that was so high that excessive spurious...

Ahh.. I apologize I thought you were asking for thoughts on whether your amp is truly clean or not.

"Only" 6 channels is still a whole lot of splatter.. a WHOLE lot. Not at all what I would call clean.. Perhaps a bit clean for an unfiltered class C box though.

^That's what I was missing.. so the max current for an amp like that would really be the datasheet Ic multiplied by (total number of transistors/2). My reply was based solely on the datasheet numbers. Your real-world mileage may vary. As to more detailed answers I'll leave that up to those...

I figure he should have the amperage stated in the datasheet as max Ic per device, but I agree that in real world usage things might be a little different. Best to have more available than less.. Also, the devices are rated per their datasheet to 100W each@28MHz, so once you push things past...

I'd say an absolute max of 800W PEP is to be expected from that amp. You're looking at 25A peak collector current per device @ 800W, so I'd say you'll need at least 200A peak input plus a little headroom.

That doesn't look bad at all, especially for the price. It'll handle 500W, which is quite a bit more than this kit will handle. It also includes 6m so that's a bonus. I'd go for it if you've got the cash..

OK, so now that the drama has subsided (for now lol) here's a final update.. IT'S DONE!! Once I had my hands on a good L/C meter I was able to tune the toroids for a very acceptable input SWR of 1.5 or less across all bands. Took her for a test drive with a buddy of mine on 20 and 40m and it...

^You'll never guess what was was included right there in that ebay listing in the link Klondike Mike provided..

HOLY FREAKING CRAP!!!!!!!!!!! Kamikaze posted some valid technical information! OMG OMG!!!! Unbelievable.. This deserves some sort of commendation! I'm almost sorry I've been hounding the crap out of you for trolling constantly Kamikaze.. maybe you do know a thing or two. See, I...