Marshall Amplification Field Marshall 100 User manual

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Owner’s Manual
OWNER’S GUIDE

Page 2
Field Marshall Tracking Receiver
Contents:
Introduction........................................................................3
Getting Started..................................................................4
Receiver Controls........................................................6-11
In the Field—AQuick Tutorial .....................................12
FrequentlyAsked Questions........................................16
Advanced Telemetry......................................................23
Radio Propagation..........................................................28
Tracking Strategies........................................................34
Warranty..........................................................................40

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Owner’s Manual
Congratulations onyour purchase of the all new digital Field Marshall receiver.
It combines superior range and convenience in a compact and rugged design.
The Field Marshall is great for tracking Marshall Transmitters under any condi-
tions (see page 37).
- More frequencies (100, 800, 1000, or 4000 frequency models).
- Broad and smoother tuning.
- Increasedrange (more than anyother receiver, and equal to
the Marshall Stealth).
- Much less noise and static interference
- Pinpoint accuracy (to within inches of the transmitter).
- Omni-directional sound.
- Smaller, narrower size.
- More ruggedantenna design.
- Quick-Release handle.
- Improved range detection.
The digital Field Marshall won’t sound likeyour old receiver, because it has
unique Polyphase Filters that dramatically reduce the background noise. The
quietness means thatyouwill hear the desired signal crystal clear and be able
to keep thevolume down without blastingyour ears with noise.
This quietness translates into better range and increased speed in finding your
transmitter.
Introduction

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Field Marshall Tracking Receiver
The Quiet One ™
When you turn on your Digital FieldMarshall, you’ll notice the
quietness immediately. You usually won’t turn it up asloud as
your old receiverbecause you don’thave to. While other
receiversare producing lots of noise, the new Field Marshall is
producing more signal.
How does the digital FieldMarshall’s lower noisetranslate intobetter range? Well,
the answer is that with all receivers it’s the noisefloor of the receiver that ultimately
limits its range. Any receiver can amplifya weak signal froma farawaytransmitter.
The problemis that when youturn up the volume to amplifythat weak signal the
noise just gets louder as well andcontinues to overpower the signal*. That’s why
the difference between a mediocrereceiver andthe best receiver is sophisticated
filtering and expensiveelectronic devices that minimizenoise. Itturns out that’s the
only way toincrease the range of a receiver. Other receivers simply make aloud
sound, but loudness alone means nothing interms of range.
* The technical term for thesensitivity of a receiver, or its ability to discern weak signals,is
the signal-to-noise ratio.A higher signal-to-noise ratio translates directlyinto better sensi-
tivity and range, regardless of howloud the actual output of the receiver is.
“The Quiet One” comes through with a more effective and pleasant
tracking experience.
Introduction, cont.

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Owner’s Manual
Getting Started
The first thing to understand is howto deploy the collapsibleyagi antenna,
which is a full-size three element Yagi Antenna for maximumrange and
pin-point accuracy, using Marshall’s patented design.
1
Remove the receiver
from whatever carrying case you
are using (hunting bag, holster or
carrying case) and hold it pointing away.
2
Push forward on the rear
of the slide bar. The spring-
loaded elements will automatically
(instantly!)flip out into the open position.
Warning: to avoid injury be sure to keep a
careful distance fromyour face or
others when performing this procedure.
3
Lift the Center Elements
up and out of their slots one at a
time and let them spring open .
First, remove your receiver from your
field holster or backpack.
Second, push forward on the rear of
the slide bar to release the spring-
loaded elements out into position.
Next, lift the ends of the center
elements, one at a time, up from
their notched holders. They will pop
out into their correct positions.
G E T T I N G S T A R T E D

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Field Marshall Tracking Receiver
4
Reachforward and pull the slide bar forward to fully
extend the forward elements until it clicks into place.
The antenna won’t give its best range and pin-point
accuracy unless fully deployed as shown in the
picture above.
To collapse the antenna, follow the same steps in reverse:
- Slide the Slide Bar with the two Forward Elements
back toward the receiver.
- Rotate the CenterElements into their collapsed
position.
- Rotate the two BackElements and clickthem into their
silver clips.
Finally, pull the director elements out forward until they click at their ex-
tended position. The yagi is now fully extended and ready for use.
G E T T I N G S T A R T E D
REMEMBER!

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Owner’s Manual
5
Turning It On
The receiver is turned on by rotating the Volume Knob on
the front panel. It turnsoff again by turning to the left with a
final click.
6
Tuning
The frequencyis selected with the three numbered
switches (two switches in
the case of the FM100.)
Theyindicate the kilohertz (KHz) of
the frequency.
The frequencyof the receiveris
very accurate (within one KHz) but
to get the best tone may need to set
the frequency1 to 3 kHz above or
below the frequency marked on your transmitter. This is perfectly
normal. If you can’t hear the signal at all, try moving through the
whole range of numberson the rightmost digit. For example, if your
transmitterismarked 216.025 you may end up tuning somewhere
between 216.022 and 216.028 (possibly even further away.)
The FM4000 Model has a Band
Switch which givesyou a choice
of which megahertz(MHz) band
you want to tune to. (For example,
each of the 216, 217, 218, and 219
MHz bands.)
The Fine Tune Knob isavailable so you
can adjust the frequency slightly (within one
KHz.) The tuning isvery broad and not “touchy.”
When tracking an extremely weak signal this
knob isuseful because you will get the best range by adjusting the
Fine Tune to the strongest pitch (about 700-800 Hertz, or the upper
end of the treble clef on a piano).
For everyday tracking you can set Fine Tune anywhere you want –
many people prefer veryhigh tonesbecause theyare sound so
clear. Just tune to what soundsbest to you.
The F 1000
F 1000F 1000
F 1000 gives 1000 different frequency
choices.
The FM4000
FM4000FM4000
FM4000 gives 4000 different frequencies
choices by providing a Band Selection Switch.
G E T T I N G S T A R T E D

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Field Marshall Tracking Receiver
7
The Range Switch is provided to be
able to estimate the distance to the trans-
mitter, a process called ranging. When
you are driving inyourvehicle toward the
transmitterfrom a distance, the key question often
is, “when should I get out and start walking?” A
common mistake is getting out on foot too soon,
thinking you are near enough to walk. The
Medium setting helps you avoid this mistake.
When the signal can be heard on Medium, you’re
close enough to get out and search on foot.
Note: Other receivers have powerful Medium settings which tend to fool
you into thinking a transmitter is closer than it is. This high sensitivity is
good on Far, but on Medium, this is not a virtue. The Field Marshall is
intentionally designed with a weaker, and more precise Medium range.
The Near range setting is not
used in ordinary tracking. In
extreme situations it allows
you to accurately pinpoint a
transmitter which is very near
but hiddenfrom sight.
The Far range setting is for use in all situations when the signal is too
weak to be heard on Medium.
Comparing the range of two receivers set on Medium is like racing two
cars in only second gear — winning means nothing because the gear ratios
are arbitrary. Only compare performance of receivers with the ranges of
both receivers set to Far. To have a race, put them both in high gear.
8
As with any receiver,you want to avoid
overdriving it. This happens when you
turn up the Volume toofar. Overdriving
doesn’t hurt the digital Field Marshall, but
makes it soyou get the same signal in
every direction, (sometimes the signal may
actually decrease in the direction of the
transmitter.)
Solution: If the Receiver has lost directionality simply turn down the
Volume ,or switch to Medium or Near .
G E T T I N G S T A R T E D
Setting Action
Far Stayin car
Medium Start Walking
Near Lookaround you

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Owner’s Manual
Maintaining Directionality.
Avoid deflecting the Metermuch more than fullscale
(the Meteris not much use then anyway.) This can be
done by switching to Mediumor Near or just turning
down the Volume.
Batteries
The digital Field Marshall uses six AAA
1.5 Volt batteries. You can use any name
brand Alkaline batteries, although more
expensive Lithium batteries can be used
for longer life. (Older style Zinc-Carbon
batteries are not recommended.) AAA
Lithium 1.5V batteries work better in cold
weather (below about -7ºC (20º F).)
Actual battery life depends on many factors, including temperature and
how long it is used continuously. All batteries will run longer if usedfor
short periods of time with time to rest in between (rather than continuously
with no rest.)
Caution: Please observe the battery
polarity as shown in the picture and
marked on the battery cover lid – negative
on the two sides and positive in the
middle.
Energizer
Battery Typical Life
(hours)
Cost per
Hour
(USD)
AAA Alkaline 10.5 $.36
AAA Titanium 11.5 $.65
AAA Lithium 14.0 $1.07
Other Features . . .
The Low battery Light will begin to
co e on when it is ti e to change
the batteries.

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Field Marshall Tracking Receiver
External Power
The External Power Jack isavailable for
use with a standard 12 volt automotive
cigarette lighter adapter with a negative
ground. You can also use DC voltage
from any external source between 7.5
and 14 voltsthat can supplyup to 200
mA.
Batteriesin the receiver cannot be
recharged through the External Power
Jack.
Quick Release Handle
The handle can be conveniently removed
if desired by simply
turning the thumbwheel and
sliding the handle out.
Water
The Field Marshall isvery water resistant, and the speakers are
completely waterproof. It should have no problem with an ordinary
rainstorm aslong asyou shield the Front Panel from the direct
spray of the rain. That said, the receiverisnot warranted against
any water damage.
If water does get into the receiver (or if it has unusual behavior after
exposure to water):
First: Immediately turn off the re-
ceiver and take the batteries out.
(Wet batteries may swell up and
become impossible to remove.)
Set the receiver on a flat surface
with the Front Panel tilted downward
so the water drains out the bottom
of thefront. Don’t turn the receiver
back on until it is completely dry.
The “drying out” position

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Owner’s Manual
Headphones give a big advantage when tracking weaksignals
in noisy environmentsand are strongly recommended for
serious tracking and listening to very weak signals.

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Field Marshall Tracking Receiver
In The Field – A Quick Tutorial
Basic Tracking
The best way to become familiar with your receiveristo use it
outside. Turn on a transmitter and place it about 100 yards
away. Set the Range Switch to medium. Adjust theTuning
Knob until you hear a clearbeeping tone from the transmitter.
Adjust the volume to a comfortable level.
Hold the receiver in front of you at eye level with the elements
horizontal. Now,rotate your body360°, keeping the receiver in
the same position. Can you hear the volume of the beep
change asyou turn around? Was it strongest when you pointed
it at the transmitter? This isthe basictechnique of telemetry:
Scan the horizon with the antenna until you get the strongest
signal. That will generallybe the direction that will take you to
the transmitter (that’snot alwaysthe case, though; see the next
chapter for more about this.)

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Owner’s Manual
Vertical vs. Horizontal
Now, point the receiver at the transmitteragain and rotate the
antenna until the elementsare vertical. Did the strength of the
signal change? Or wasit strongest somewhere in-between? In
most cases, one orientation will be stronger than any other.
This is important: Make it a habit to rotate the receiver from
horizontal to vertical every time you use it at a new location.
Practice:
1. Have someone hide the transmitter in a difficult spot and see if
you canfind it. You can make a game out of this. (Thousands of
ham radio enthusiasts actually conduct competitive transmitter
hunts in major cities in the US and around the world.) Or, put the
transmitter on a person, give them a head start, and see if you
can track them down.
2. Hang the transmitter with the antenna vertical on a wooden
object or a string and drive away with your receiver (don’t set it
on the ground, though; transmitters always perform poorly on the
ground.) See howfar you can go before losing the signal. Try
tuning in the signal when it is very weak. Experiment with all the
controls and see what effect on the signal they have at a dis-
tance.

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Field Marshall Tracking Receiver
In the Field
When you’re readyto use the system in the field, tune in the
signal just before letting your bird or dog go.That ensuresyou’ll
be ready with the best signal instead of having to try to locate it
in the rush of the moment when the animal first becomeslost.
A few pointers on tuning:
• Set the numbersto match the frequency shown on the
transmitter. From there you might rotate the third num-
ber up ordown to get the best signal.
• Tune the receiver for the loudest sound after the trans-
mitterison the animal and hasreached the outside air
temperature. This is not necessary with Marshall trans-
mitters but other brandscan experience frequency drift
with changes in temperature.
• If you tune in while the transmitter is sitting next to you
on the car seat, the signal will be so powerful that your
receiver may pick it up on adjacent or incorrect
channels. If you mistakenlytune in on the wrong chan-
nel the signal maysound fine in the car, but will be
quickly lost when the transmitterisfar away. To avoid
this, set the Range Switch on Near while tuning any-
where near the transmitter.
Trylocating youranimal several timesfor practice. Experiment
with holding the receiverantenna vertically and horizontally
while watching the position of your animal. Use the system
many timesuntil you feel confident in finding your animal with
telemetry. When your bird or dog islost is not the time to be
learning how to use telemetry.

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Owner’s Manual

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Field Marshall Tracking Receiver
Frequently Asked Questions
Why does myreceiver pick up allmy transmitters at
the same time? They’re on different channels.
Extremely strong signalswill get through even the most power-
ful filters in a receiver. If you have transmitters on adjacent
channelstransmitting right around you, you might hear a pop-
ping or thumping sound from them. This can be a distraction
when you’re trying to pickup a very weak signal from a lost ani-
mal.
The solution is to turn off the transmittersaround you while you
tracka lost animal. If you’re just tuning up, switching the Range
Switch to Near will help to remove the unwanted signals.
I lost the signal and tried to tune it in. I couldn’t get it
again.
If you lose the signal,don’t panicand tune all over the dial.It’s
essential not to lose the correct tuning. The signal mayhave
drifted, but not much. So if you really think the signal could
have drifted, take note of the setting and then just turn the
Tuning Knob very slightly and search for the signal by scanning
the horizon 360º. If you don’t find it, you’re out of range. Turn
the Tuning Knob back where it waswhen you last heard the
signal and go to higherlocation and try again.
I could only pick up a transmitter a half amile away.
Thisusuallyhappensbecause the transmitterisputting out a
weak signal. The range of transmitters varies tremendously,
depending on where they are. A transmitter on the ground may
go lessthan half a mile. If the antenna ispointing directly at
you, you may hear almost nothing.
If the transmitterisputting out a good signal,the problem is
almost always improper tuning of the receiver. It’spossible to
tune to a tone that sounds like your transmitter, but is actually
at the wrong frequency (or even on the wrong channel!) It will
sound fine when you’re right next to the transmitter, but when
you get in the field it becomesweak(This can happen on any
receiver.)

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Owner’s Manual
To avoid this, set your receiver on Near when you tune up –
thisremovesall but the real, genuine signal you want to tune
to. And stand a short distance away when you tune up.
What is the single most important thing to do if I ab-
solutely don’t want to lose my animal?
Put a backup transmitter on the animal. The second transmitter
can be a smaller one, or perhapsone with longer batterylife (a
good combination would be one extremely powerful transmitter
that you can use the first few days, and another that lastsa
long time, in case you don’t find it right away.) Just remember
this: if your animal has a working transmitter, you can almost
always find it. It may take hiring a plane to fly over the area, but
eventually you can find it if you’re patient and there isa signal.
I’m not exactly certain what direction the transmitter
is. Am I doing something wrong?
Getting the sharpest bearing to your transmitter saves a lot of
searching (that’swhy Marshall receivers use a full size, three
element yagi antenna).A three or five element yagi ismore
precise, and a two element antenna is almost worthless. But
the following, easy technique can help you get a more accurate
bearing.
Instead of trying to find the strongest signal, try to find two
points on either side of it. Scan to both sidesof the maximum
signal and notice the pointson the horizon where the signal
drops exactly 1 unit on the S-Meter. Your best bet isthat the
transmitterishalfwaybetween those two points.
By the way, the wrong setting of the Range Switch could cause
thisproblem, too. See the following question.

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Field Marshall Tracking Receiver
Why is the Range Switch necessary? My other re-
ceiver didn’t have one.
The Range Switch isa feature that allowsyou to get a rough
idea of the distance to the transmitter.
If the signal isvery strong and you don’t switch down to Me-
diumor Near, the receiver will not point out the right direction
very precisely. The strong signal also saturates the receiver,
making all signalssound equally loud. Thisis common to all
receivers.
How can I tell how far awaymy transmitter is?
One of the biggest challengesin telemetry is determining dis-
tance. There isno scientifically sound wayof getting the dis-
tance from a transmitter signal. You can easilybe deceived by
a loud signal from a transmitter very far away. However, there
are a couple of tricksto estimating it:

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Owner’s Manual
Distance Technique #1: Let’sassume you are receiv-
ing a strong signal with the Range Switch on Far. Now
flip the switch from Far to Medium. If the signal remains
strong, itmeansyou are fairly close to the transmitter.
With a strong signal, here are typical rangesto a trans-
mitternear the ground:
Near............................Less than 200 feet
Medium........................About1/2 mile
Far...............................Over 1/2 mile
The above table is only an example; you won’t get the
same results. It depends on your transmitter, the ter-
rain, and manyother factors. But over time you’ll get a
feel for the distance these Range settingsrepresent
with your transmitterand terrain.
Distance Technique #2: Just take a reading on the S-
Meter and then proceed in the direction of the transmit-
ter until the meter reads twice as much. You will have
covered approximatelyhalf the distance to your target.
Thisonly works with direct line-of-sight signalsof the
same polarization and givesonlyan approximation.
Still, it could save you from driving milesout of your
way. Adjust the Volume Knob during the first reading so
the meter readsabout a third of full scale (where it is
likely to be the most linear.)

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Field Marshall Tracking Receiver
What is a KHz and a MHz?
These are measurements of frequency. Everytransmitterhas a
unique frequency that makes it distinguishable from all others.
Fortunately, a receiver can tune into a single frequency at a
time and reject all the others.
The basic measure of frequency isthe hertz. It represents one
cycle or vibration per second. A kilohertz (kHz) is a thousand
cycles per second, and a megahertz (MHz) isa million cycles
per second.
An AM broadcast station is fairly in lowin frequency, perhaps.7
MHz, while an FM station is much higher, say at 105 MHz. Your
telemetryoperates at a still higher frequency, such as216.055
MHz.Thus, a single short pulse from your transmitterismade
up of several tensof millions electro-magnetic vibrations.
The kilohertz unit is usuallyused in telemetry to measure the
difference between frequencies. For example, if you had a sec-
ond transmitter at 216.070, it would be 15 kHz higher than the
one mentioned in the previousparagraph. .
Is there an easier wayto getthe receiver in and out of
the car.
It’sa lot easierif you push the sliding channel closed, partially
collapsing the antenna. However, don’t forget to extend it when
using the receiverin order to get maximum performance from
the antenna.
How can I use my Marshallreceiver with my car top
antenna? It’s got a different plug.
Marshall receivers use high reliability, lightweight, gold-plated
SMB connectors. Call to order a short adapter that will fit the
larger BNC connectorsused on some other antennas.