Trish's FT-817 QRP Page

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FT-817 Projects Page

The 817 is a pretty well designed and nicely compact little unit that for us at least has left us with very few "wants", there are a few though.

Most notably the unit lacks an automatic antenna tuner and does not have a DSP noise reduction capability.

Antenna Tuner
When it comes to operating QRP the best advice we can give is make sure your antenna is as close to 1:1 SWR match as possible.  On the ypical 100w rig an antenna that doesn't match well can still get results but when you are running 5 watts or less every milliwatt counts.  Using an antenna that is not matched to your operating frequency simply wastes your transmitters power by reflecting back at the transmitter rather than radiating to that elusive QRP contact.

That being said there are times when one is forced to use an antenna that is less than ideal, perhaps your antenna is very narrow banded which is often the case in portable HF antennas, especially on the lower bands, or perhaps the weather is bad and you can't get outside to make adjustsments at the moment.  That's when it's nice to have an antenna tuner availalbe.

There are quite a few options out there for tuners but at the time Iwe were looking for a kit, something we could build.  This is where our first encounter with Elecraft came in, in a time before the KX3 existed.  Elecraft's T1 Miniature 20W Autotuner http://www.elecraft.com/T1/T1.htm is a perfect mate for the FT-817 both in size and capability.  Besides being about the size of a pack of cigarettes only thinner it can talk to your 817 for automatic band changing and runs on a 9v battery.  It's also available pre-built if you prefer.

We found the kit easy to build and a rewarding experience but it also expanded our knowledge on the therory on how such devices work.  We chose the kit where you got wind your own coils but I beleive you can buy the coils prewound as well.  We were pretty eager to get into this project, if memory serves it took about two days of tinkering to assemble and test the unit.  We've had it now over 10 years, it's prove to sturdy and reliable.

DSP Noise Reduction
A year or two after getting our 817 we'd noticed that there had quite a few instances where we would hear people "in the weeds" usually due to poor band conditions, a less than ideal antenna, or perhaps locally generated noise.

Searching for options it seemed the choices were either an external powered speaker with a built in DSP or a nifty project from bhi, their model NEDSP1061 DSP noise cancelling module which is installed into the radio itself.  Not wanting to carry any more than we need to while portable and wantign to keep the power costs down we went with the NEDSP1061.  Here's the link to bhi:  https://www.bhi-ltd.com/noise-cancelling/pcb-modules-low-level-audio/nedsp1061-kbd.html The unit can be purchased in the US from W4RT here: http://www.w4rt.com/BHI/DSP-817.htm.

This project will require you to open your 817, solder, and desolder wires, and drill one or more holes in you chassis.  If these facts scare you a little you can also send your radio in to W4RT to have the module installed.

This project is well worth the money and effort to install, the results ar esimply incredible.

If you've read some of our other posts on this site you know that power consumption is something we pay close attention to.  The DSP will add 30-40mA of draw on your batteries.  Because of this we added a DPDT switch to the back panel of our 817 so that on one position the DSP is removed from the circuit to save power and in the other it is enabled.  It's been many years since I made this mod so I no longer recall off the top of my head the exact details of how I did it.  If you have a background in electronics you should be able to figure it out as we did.  If you're desperate for a how to ping me.  If I'm not particularly busy I'll try to reverse engineer the process for you.

Power
We bought an FT817 to revisit the joys and challenges of working low power DX that for me at least began when I was kid and discovered SSB DX on channels 37-40 on CB radio in the lat 80's and early 90's.  We apodted the "power" project not so much because we needed our 817 or KX3 to run at 100 watts, if we want to operate with power we have our base rig and mobile mounted radios that can do around 100 watts.  What we were really looking for was a project, a kit to build.  That's we we decided to build an Elecraft KXPA100 amplifier.  http://www.elecraft.com/elecraft_prod_list.htm#kxpa100

The kit took a couple of afternoons to assemble.  Unfortunately the kit was much more modular than the Elecraft T1 auto tuner.  No coils to wind, no soldering, just assembly.  If we sound a little disappointed it's because we were looking forward to the challenge of building something complex.  Were not at all disappointed in the capabilities of the KXPA100.  It works beautifully with both our 817 and KX3, both radios can push the amplifier up to as much as 110w actual output power into a well matched antenna.  It's worth mentioning that the output power will vary depending on what band you are operating due to various efficiencies related to frequency.

It's a nice unit to have when you're portable and the band conditions will not allow reliable QRP contacts or if you have an emergency and need to contact help.

It's worth noting for those "CB'ers" out there that this amplifer is not for you.  It has a factory designed lock out to prevent it from being used on the 11m band and cannot be adapted to work there.  If you're a CB'er you should think about getting an amateur radio license if want more power and fun!