Rick Disney wrote:

Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?


Easiest would be to move the 3.5 - 4.0 band up to
say 4.2 - 4.7, but you would have to sacrifice
the original band.

You might be able to switch components the "pad" the
existing components in and out to get both the ham
band and Mars.

Start with getting the manual and schematic from:
http://bama.sbc.edu/heath.htm

Examine the schematic and rig to determine which
coils/capacitors are switched in for the 80 and
40 meter bands. You'll see that the circuit is the
same for each band, but the values of the components
are different. Remember to do this both for the
transmitter and receiver portions of the transceiver.

Once you have a firm understanding of how Heath
switches from one band to the other, you will be
able to "functionally" design (specify what components
to use, and where they need to go in the circuit, but
no component values determined yet) for your new band,
which should start at something like 4.2 or 4.3 mHz.

The manual probably has a theory of operations or
circuit description section which will help you
to understand those circuits.

Next, you establish component values that will make
your new circuit work at the design frequency -
4.2 or 4.3 mHz.

Next, determine how you can incorporate the new
components into the rig. Are you willing to give up
the 3.5 - 4.0 range, or any other band? Can you
add a switch to switch in new components, such that
you don't have to give up any existing band?
Essentially, you need to figure out whether major
surgery is required, and whether you are willing to
do it.

73's

Rick KAØDIZ

Rick Disney wrote:

Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?


Easiest would be to move the 3.5 - 4.0 band up to
say 4.2 - 4.7, but you would have to sacrifice
the original band.

You might be able to switch components the "pad" the
existing components in and out to get both the ham
band and Mars.

Start with getting the manual and schematic from:
http://bama.sbc.edu/heath.htm

Examine the schematic and rig to determine which
coils/capacitors are switched in for the 80 and
40 meter bands. You'll see that the circuit is the
same for each band, but the values of the components
are different. Remember to do this both for the
transmitter and receiver portions of the transceiver.

Once you have a firm understanding of how Heath
switches from one band to the other, you will be
able to "functionally" design (specify what components
to use, and where they need to go in the circuit, but
no component values determined yet) for your new band,
which should start at something like 4.2 or 4.3 mHz.

The manual probably has a theory of operations or
circuit description section which will help you
to understand those circuits.

Next, you establish component values that will make
your new circuit work at the design frequency -
4.2 or 4.3 mHz.

Next, determine how you can incorporate the new
components into the rig. Are you willing to give up
the 3.5 - 4.0 range, or any other band? Can you
add a switch to switch in new components, such that
you don't have to give up any existing band?
Essentially, you need to figure out whether major
surgery is required, and whether you are willing to
do it.

73's

Rick KAØDIZ

In article , Rick Disney
says...

Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?

I've not had experience with that specific radio, but... assuming
it's a simple VFO, it should be a simple matter to tweak coil(s),
capacitor(s), or both to bring the low end up a bit. If you're going to
tweak coils, I suggest using a grid dip meter to find a good spot.

You should probably get hold of the manual for the unit first. Do
a google search for 'W7FG vintage manuals.'

Good hunting.


--
Dr. Anton Squeegee, Director, Dutch Surrealist Plumbing Institute
(Known to some as Bruce Lane, KC7GR)
kyrrin a/t bluefeathertech d-o=t c&o&m
"Quando Omni Flunkus Moritati" (Red Green)

In article , Rick Disney
says...

Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?

I've not had experience with that specific radio, but... assuming
it's a simple VFO, it should be a simple matter to tweak coil(s),
capacitor(s), or both to bring the low end up a bit. If you're going to
tweak coils, I suggest using a grid dip meter to find a good spot.

You should probably get hold of the manual for the unit first. Do
a google search for 'W7FG vintage manuals.'

Good hunting.


--
Dr. Anton Squeegee, Director, Dutch Surrealist Plumbing Institute
(Known to some as Bruce Lane, KC7GR)
kyrrin a/t bluefeathertech d-o=t c&o&m
"Quando Omni Flunkus Moritati" (Red Green)

Rick Disney wrote:

Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?

73's

Rick KAØDIZ

Each band has a crystal oscillator that sets the band of frequencies. Change
that
crystal to a different one that will cover the frequency you want.

Bill K7NOM

Rick Disney wrote:

Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?

73's

Rick KAØDIZ

Each band has a crystal oscillator that sets the band of frequencies. Change
that
crystal to a different one that will cover the frequency you want.

Bill K7NOM

"Rick Disney" wrote in message
...
Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?

73's

Rick KAØDIZ


Rick -

I would also suggest that you review the article "Optimizing the Heathkit
HW-101" by
Mark Graalman WB8JKR (Adobe Acrobat)
http://members.tripod.com/NRWILLIAMSON/Hw101.pdf

Photo
http://oak.cats.ohiou.edu/~postr/bapix/HW101.html

Improving the HW-101
http://www.fvh.accessus.net/~dwentz/...ray_k4jpn.html

Partial manual and schematic (BAMA)
http://bama.sbc.edu/heath.htm


g. beat
w9gb

"Rick Disney" wrote in message
...
Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?

73's

Rick KAØDIZ

..... I forgot the service bulletins
http://www.qsl.net/kb7rgg/heath/Serv...s/sb-hw101.doc

w9gb

"Rick Disney" wrote in message
...
Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?

73's

Rick KAØDIZ


Rick -

I would also suggest that you review the article "Optimizing the Heathkit
HW-101" by
Mark Graalman WB8JKR (Adobe Acrobat)
http://members.tripod.com/NRWILLIAMSON/Hw101.pdf

Photo
http://oak.cats.ohiou.edu/~postr/bapix/HW101.html

Improving the HW-101
http://www.fvh.accessus.net/~dwentz/...ray_k4jpn.html

Partial manual and schematic (BAMA)
http://bama.sbc.edu/heath.htm


g. beat
w9gb

"Rick Disney" wrote in message
...
Greetings ,

Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center
tuner only
adds 500 hz...Navy Mars operates at 4470.5. ..Any help?

73's

Rick KAØDIZ

..... I forgot the service bulletins
http://www.qsl.net/kb7rgg/heath/Serv...s/sb-hw101.doc

w9gb