Frank and All, There are some very good small amps out there. Tokyo Hy-Power now offers an HL-45 that will run about 50 watts or so, and is a very good product. I have their older version, the HL-50B, and it is a superb product as well. It is particularly useful with the numerous little QRP rigs I have around the shack when conditions just aren't that great for 5 watts or less. Another good product is the HF Packer amp, which has been upgraded to quite a nice package.
Problem is, these add-on amps are cumbersome, unless you plan to use them with several different rigs like I do. Also, they aren't cheap, even if you find one that is used. If you are just planning to use one with your K3/10, I'd very strongly suggest you bite the bullet and just add the Elecraft amp module. It's probably even "pricier" than the alternatives mentioned above, but the convenience factor looms large. It fits neatly inside your K3, doesn't necessitate a bunch of extra connecting cables, interfaces very nicely with your K3's firmware, etc. Then you would have a fully controllable amp, all in one package, that you can simply dial up the power you want. This is a lot more convenient than you might think, and especially if you realize that more often than not, you don't really need to go all the way to 100 watts, or even close to that, to improve your ability to communicate in tougher conditions. 50 watts or less may be all you really need, and you wouldn't get much more than that anyway out of the others mentioned above. When 10 watts or less is sufficient, you simply dial that up, and the amp module is effectively disengaged. In my view, this is absolutely your best option, provided you can swing the cost issue. If cost is a significant issue, there is one other type out there I'm familiar with, and frequently I see them offered for a much lower price (used). These are the ones from RM Italy. I have an HLA-150, and it is a pretty good amp--actually will run more than 100 watts. It's also auto band switching. If you get one of the "HLA" series, they do have proper bandpass filtering. Other models apparently don't. My biggest problem with this amp is that it's RF sensing capability isn't great--not like the Tokyo Hy-Power models. So, you really need to key it directly, which is a problem with most of the little QRP rigs I have, since they don't have a keying line. Thus, this amp tends to clip dits and dahs here and there unless you do hardwire the keying. Anyway, I've seen these being sold for something around a dollar a watt or so--a good bit cheaper than the others I mentioned. There are also some concerns about this amp's purity when run up around it's stated capability. At 100 watts or less, however, it seems to be acceptable. W8JI did some extensive testing on this, and you might want to check out his comments if you are interested. Bottom line--get the Elecraft amp module if at all possible. In the long run, you won't regret it. Dave W7AQK ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
