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.
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
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
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
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:
The unit can be purchased in the US from W4RT here:
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.
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
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!