Martin RF Supply
Offering A Wide Selection of New and Used Bird RF Wattmeters and Bird RF Loads. Since 1973 our RF engineering and products
experience helps with your RF Power Measurement solutions. Huge inventory of Bird
Model 43 Slugs!
Bird Elements List for Model 43 Wattmeters
New and used wattmeters by Telewave, Coaxial Dynamics and Bird Electronic. Call us for assistance in your selection
of RF Watt Meters and RF Loads
at (781)648-2097 9-5 EST or use the menu on the left to select the items you
require. If you don't see a menu on the left then click the Martin RF Supply link at the start of this paragraph.
Order directly on-line with our easy to use shopping cart. Payment accepted by credit card, PayPal, or
checks, and bank wire transferss. All RF Shop sales have a 100% satisfaction Guarantee!
Next Day Shipping on most items!
Domestic and International Sales are Welcome.
Coaxial Dynamics RF Wattmeters
The Coaxial Dynamics RF products are very
high quality, reliable, and affordable and offer an excellent
alternative to the Bird RF products. The Martin RF Shop stocks a large inventory of new
wattmeters and plug-in elements manufactured by Coaxial Dynamics. The meters
have an in-line design and are similar in design to the Bird Electronic Thruline(c) wattmeters.
The Coaxial Dynamics and Bird plug-in elements (or "slugs") are interchangeable. There are several models of
Coaxial Dynamics wattmeters available for
average reading, peak reading, broadband (no plug-in elements required) and other applications.
A Two year limited warranty on all Coaxial Dynamics products assures your
complete satisfaction. If you already have a collection of Bird slugs they will work just fine in the Coaxial
Dynamics wattmeters.
Telewave Broadband RF Wattmeters
The Telewave Wattmeters are an in-line
design wattmeter that require no
plug-in elements and cover a wide frequency range and power range. If your RF
power measurement requirements involve
multiple frequency ranges and power ranges the Telewave wattmeters will be much less
expensive in the long run as you save by not requiring multiple plug-in elements. There are
Telewave wattmeter models available for both HF/VHF
(2-200 MHz) and HF/VHF/UHF (20-1000 MHz). The Martin RF Shop stocks new and used Telewave wattmeters.
The Bird Electronic Model 4304A is similar in design to the Telewave design and uses a
single permanent plug-in element for broadband power measurement.
Bird Electronic Thruline RF Wattmeters
The Martin RF Shop offers a wide selection of used Bird Electronic
wattmeters, plug-in elements,
RF samplers, RF Loads, and other RF Products. Thruline is Birds name for the RF
coaxial line design that they use to sample the RF in two directions. A Thruline
(or in-line) wattmeter has two RF connections (input and an output) and is used
in series with the RF Load or antenna. We have a large selection of Bird
Thruline wattmeters. All used products are fully tested
and you're guaranteed 100% satisfaction. We have the best inventory of plug-in
elements (Bird Wattmeter Slugs) in the world and can provide next day shipping
on all the popular element ranges. We also maintain a very large inventory of new plug-in elements by
Coaxial Dynamics and they are 100% compatible with Bird Model 43 style
wattmeters.
Wattmeter Elements
The Bird Model 43 and other similar in-line
wattmeters require plug-in elements (or Bird slugs). A variety of Bird slugs are available
to cover a wide range of frequencies and power levels.
The Martin RF Shop offers the best selection of new and used wattmeter elements in the world!
Each used element is tested immediately before
shipping and your satisfaction is guaranteed. New wattmeter elements by Coaxial Dynamics are factory calibrated,
100% compatible with Bird elements, and have a two year
manufacturer's warranty. If you require a traceable calibration for your RF power
measurements you should purchase a new element.
Wattmeters That Require Plug-in Elements
The most economical and commonly used RF wattmeter is the Bird Electronic Model 43.
Bird
RF Wattmeters. I've been selling
and using this model since 1967. The Bird Model 43 is the industry standard and is the benchmark for performance and
reliability in routine RF power measurements.
The Model 43 requires
plug-in elements (often referred to as "slugs") for the frequency range and power range
for which the meter is going to be used. There is a large selection
of elements available that cover the frequency range from 0.45 MHz to 2.5 GHz in power ranges from less than one watt to
10,000 Watts. The Bird Model 43 is an in-line wattmeter that reads forward and reverse power. From these two measurements
it's possible to easily calculate the SWR (Standing Wave Ratio) from the RF load (antenna, amplifier, filter, etc.).
The connectors on the Model 43 can be Type N, UHF, TNC, BNC, etc., and are easily changeable with only a screwdriver required.
Many users purchase multiple connectors and have them available for quick changes when needed.
It's a good idea to have an RF Load available to terminate one end of the
wattmeter if you are going to measure transmitter output power and do not want
to use the antenna as a load. The Martin RF shop has a large selection of
RF Loads
for you to choose from.
Coaxial Dynamics manufacturers high quality RF power measurement products similar to the Bird Electronic
products and provides an excellent alternative to the Bird Wattmeters. The two manufacturer's
plug-in elements are interchangeable. New Coaxial Dynamics products are offered with a 2 year
limited warranty to assure your satisfaction.
RF Wattmeters Without Plug-in Elements
There are many RF Wattmeters that do no not require plug in elements. For
example the Bird 4304A and all of the Telewave wattmeter
products
Telewave RF Wattmeters.
These meters cover a wide frequency and power range without the need to purchase expensive elements.
The meters have front panel
switches that select the power range from 5 Watts full scale to 500 Watts full scale.
Although, these broadband RF Wattmeters are
more expensive initially, you will avoid a lot of expense by not requiring
multiple plug-in elements or slugs in the future.
Bird QC Connectors
Telewave, Inc. manufacturers a low frequency (2-200 MHz) and a high
frequency (20 MHz to 1000 MHz) model of this type meter.
You should note that the maximum power of 500 Watts on these style, as well as other RF wattmeters.
is the RMS or average
rated power. If you are
measuring single side band (SSB) PEP (peak envelope power) the meter can be used at much greater
than 500 Watts. As long as the average
power is less than 500 Watts it will be displayed correctly on the wattmeter. When measuring
RF power of SSB voice transmissions wattmeters will display the average power which is
considerably less than the peak power. In other words, a 500 Watt maximum power
scale will be adequate to measure SSB voice transmissions up to 2000 watts. For more details on
this subject visit this link
Power - What's It All About.
To measure true peak power you will need a peak measuring wattmeter like the
Bird Model 43P, 4314 and APM-16. See more on these meters below.
Bird Model 4410(A) Single
Element Multi-power Ranges
The Bird Model 4410(A) uses special broadband elements to provide multiple power
ranges using a single element.
With the Model
4410(A) only a few elements are required to cover the frequency range of 0.5 to 1000 MHz and 1 Watt to 10,000 Watts.
This meter
provides the ultimate in RF power measurement versatility.
This is one of our best selling models and is available in several packages.
Bird Wattmeters
For an example, the 4410(A) with one HF element (2-30 MHz) has seven full scale power measurement ranges
of 1 Watt, 3 Watts, 10 Watts, 30 Watts, 100 Watts, 300 Watts and 1000 Watts. The
Bird 4410(A) elements as listed separately and are not interchangeable with the
Model 43 elements. If you plan to measure power at a lot of different
frequencies and power levels the 4410(A) will save you money in the long run by
drastically cutting the number of elements you will need to have on hand. Before
I discovered the 4410(A) I was carrying around 15-20 elements to cover the many
uses that I have for an RF wattmeter.
RF Shop Home
Peak Reading RF Wattmeters
Peak measuring RF wattmeters have additional circuitry
that allows the meter to capture and display the maximum peak power.
This is especially useful when measuring SSB voice transmission power.
The Bird Model 4314 and 43P are examples of meters with this feature. These two meters use the same
elements as the Bird Model 43. Bird Electronic
and others manufacture offer user installable modules that can be installed in many Model 43 meters
to add a peak reading feature. Look
under Accessories in the shopping cart to see these products.
The Bird APM-16 employs active circuitry to deliver
power reading accuracies of ± 5% for multiple-access technologies such as CDMA, TDMA, FDMA and
other digitally-encoded communication systems. Special APM-16 series elements
are required for the APM-16 wattmeter.
RF Sampling Wattmeters
Bird Models 4430 and 4431 and the Telewave Models 44AP and 44L1P
Telewave Wattmeters have a RF Sampling tap to provide a reduced level
sample of the RF signal being measured. This signal can be used to monitor the RF Power
with an oscilloscope or frequency counter. There are also RF samplers offered in the Accessories
category on the shopping cart that will provide RF Sampling on most wattmeters.
Wattmeter Accessories
Terminating Wattmeters/RF Load
As the name implies these wattmeters have a RF termination, usually 50 Ohms.
They are available in a variety of shapes and sizes and can be air cooled or oil
filled. They are typically good to about 100 Watts, however, there are some
models that will handle as much as 1-2 KW, for example the Bird model 694.
Adding a cooling fan to the heat radiator can extend the useful power
range of the RF load. The RF Shop offers a good selection of terminating wattmeters and RF loads available at
these two links
Wattmeter/RF Load
and
RF Loads
In-line wattmeters can be used as a terminating wattmeter by simply connecting a RF load to one of the RF
connectors on the wattmeter.
It is helpful to note that ntermittent power ratings on most RF loads are much higher than the
continuous power rating. For example a 200 Watt RF load can be used at
substantially higher power levels if the transmissions are kept to a very low
duty cycle. It's important to request duty cycle specifications from the
manufacturer to be sure the duty cycle is safe for the RF load. You may download user manuals from the product
manufacturer's website, see the links below, where some of this information may be located.
