Topic: Amp for FT-817 (Read 17036 times)

WV8WC · « **on:** June 09, 2003, 03:57:37 PM »

Before I get started, let me explain the reasoning behind this.

I know the FT-817 is not designed to be used as a base station, it's geared more for portable use, and that's primarily why I bought it, for travel purposes, which my job requires now and then. I would like to use it in a base station mode as well, and given its 5 watt output commercial amps are out of the question for the HF bands due to FCC regs. BUT, doesn't mean I can't build one.

So, when time and money (mostly money) will permit, I'd like to construct an amplifier for my rig that will boost it to, say, 50 watts or so. I'm not looking to go big gun, just enough to make ragchewing easier. I've read some material on the theory, but I want to learn more about how you go about designing one of these bad boys. Can anyone recommend some sources? Good books, web sites, etc?

N3ZKP · « **Reply #1 on:** June 09, 2003, 04:34:31 PM »

I believe the June QST has a construction article on just such an animal.

Lon

WB2WIK · « **Reply #2 on:** June 09, 2003, 05:07:45 PM »

Yep, the June QST article is a good starting point.

If you're interested in taking an easier approach, CCI in Ohio sells amplifier semi-kits that will do this job for you and only require a bit of resourcefulness and building a couple of low pass filters on your part. Those amps are based on Motorola Engineering Bulletins and make good use of Motorola's power RF semiconductor products. They're legal to sell even though they are kits and can be driven with low power, because they are not complete products, nor even complete kits and do require some homebrewing and additional parts to make them work.

I've built several of the CCI products over the years, and they work the first time you apply power to them. That, of course, is very gratifying!

http://www.communication-concepts.com

WB2WIK/6

W4CNG · « **Reply #3 on:** June 09, 2003, 07:53:03 PM »

Commercial amps are not out of the question (nor illegal if you follow the rules). Go check www.thp.co.ip/amateur/idx_hf2.htm Tokyo Hi-power model HL-50B. You are permitted to buy and/or import one per calendar year for your own use. 50 watts output 80-6 meters, band switchable, clean and legal with 5 watts input. Yes it will do 60 meters and 11 meters, you get in trouble using or connecting to 11 meter radio. It will cost you just above $300 including shipping to your door thru customs. Go to the yahoo/groups/ft-817 group and read the threads. There is some real garbage out there, but this amp is the import of choice. Or if you wish, build one. I have done both.
Good Luck
Steve W4CNG

N6AJR · « **Reply #4 on:** June 15, 2003, 10:18:50 PM »

Rm- klv 400 or klv 500 will work, cheep and available on ebay new $250 or so. Max input is 12 to 20 watts ssb, and autosensing so you don't need a rly line. pull the case off and move the jumper to pins 1&2

N6AJR · « **Reply #5 on:** June 15, 2003, 10:33:33 PM »

the apps ar KL-400 or KL-500

Author Topic: Amp for FT-817 (Read 17036 times)