For several years I have been a "happy" owner of Bird 43, then for comparative purposes I have bought more models: BIRD 4311, BIRD 4314 extended with the possibility of measuring PEP power, and a dozen measuring inserts, these are almost identical meters, differing in that the BIRD model 4311 for power measurements, PEP is battery-powered. This is not a practical solution, the model 4314 uses nickel-cadmium batteries and an internal power supply, while the charger with 220 V ~.
I also bought a model with a digital reading, BIRD 4391A
All the models mentioned above are more technically advanced than the basic model BIRD 43, above all they enable a relatively accurate measurement of PEP power, they are twice as expensive as the classic model 43
I bought some measuring inserts, at the moment I have 15 pcs.
Considering the value of the inserts, I decided to take care of their safety and order and purchased a special case for 12 inserts. The case makes it easy to maintain order, now I always know where all the "traffic jams" are. This case makes the inserts well protected against shocks or falls or other adverse external factors.
These are old and worn-out devices, they are 40, 50 years old and come from a depot. These meters were stored in poor conditions, exposed to moisture, mold, dustiness, low temperatures, exposed to shocks, often thrown, etc.
All BIRDs offered for sale are badly bruised, if they are not bruised, they have been painted. It is better to buy a battered than painted one, because in order to paint the housing, BIRD must be dismantled for the first part. If I had the confidence that a professional engineer did it, I would not have any objections.
The biggest challenge is the purchase of measuring inserts, prices are high, in addition there are a lot of sales inserts that have been repaired, because they are often damaged. In most cases, a calibration potentiometer gets inside the insert, so the insert after repair is usually calibrated. Those who repair them usually do not have adequate measuring facilities, namely: laboratory measuring equipment and engineering knowledge.
Be vigilant, quality does not always go hand in hand with the price.
The so-called. "Traders" usually do not know much about technology, but they know money very well. Because these inserts are expensive, the scale of fraud is big. Fakes that are very difficult to recognize are a big problem. Just change the cap with the word on top and we have the insert you want. The most wanted insert is the 5000H insert, that is for the 2-30 MHz range and max power. 5KW. It is enough that they will produce only the caps with inscriptions, and the insert they process, inside they modify so that it more or less correctly shows in the above-mentioned range of power and frequency, and cash earned. The customer will not know it anyway because he has nothing to compare with. NORMAL Nobody is buying 12 power meters as I did.
The whole page devoted to the repair of BIRD 43 inserts, and for the crooks the instructor on how to start processing is here:
http://www.repeater-builder.com/projects/bird-element-tour/bird-element-tour.html
The accuracy of the measurement of such a fake insert will probably be somewhere around 10%, which is the best DAIWY that I value for ergonomics, readability, convenience, but not accuracy. In that case, why do we need this expensive BIRD if the accuracy is not better than the DAIWY and the functionality is none? DAIWA is very functional and ergonomic. BIRD 43 is not ergonomic or comfortable, it is clumsy, almost armored and ugly, so ugly that it is "pretty" like Belmondo. The first impression suggests that it is more suitable for defensive purposes than for measurements. Because BIRD 43 is not cheap and is not so interesting, at least it should be accurate.
You can read more about my experiences with BIrd 43 power meters here using Google translator
http://sp5mxf.com/bird-43-thruline-rf-wattmeter
BIRD is a king, provided it is an original product, without interfering with the interior of the meter and especially the inserts
The Bird 43 wattmeter is a rugged, portable power meter with a practical way to change frequency and power ranges. Plugs are analog devices in which there is a certain dependence of indications in the function of the temperature which is not compensated. To ensure maximum repeatability, Bird 43 must be operated in an environment with very limited temperature, so-called. room temperature.
BIRD 43 has a very wide range of measured power and supported frequencies, its properties may interest us only when we reach the original, unprocessed and not repaired inserts, preferably not bruised. If we can obtain such a copy and especially inserts, then all its defects are of little importance. Many American radioamers have a BIRD 43 on their desk. In the US, this is an absolutely iconic meter, it must be in the vicinity of a power amplifier, eg KENWOOD TL-922, also cult classic.
The accuracy of the new power meter and the BIRD 43 reflectometer, including inserts, according to the manufacturer's declaration is not worse than 5%. My measurements indicate that on the original unprocessed inlays, the error does not exceed 2% at the end of the scale. When the inserts are new, unused and not bruised, this accuracy is within 1%, it is difficult to see the error visually. Such accuracy should completely satisfy the radio amateur, unfortunately used, original inserts, without the interference of the "golden handle" are practically unavailable.
Due to the high price of these inserts, the EBAY auction site is dominated by a group of several repairers and you can buy what they will find out. If we buy from someone from the case, then usually he has previously bought an insert from one of these "traders", then disappointed resells it further and the wheel closes.
The BIRD 43 power meter fits with the tolerance declared by the manufacturer, the problem is that there are no such occasions to buy new inserts and relatively cheap.
Buying a good EBAY cartridge is a great lottery, if it is not very popular, the chances are good, but such inserts as 100H, 250H, 500H, 1000H, 2500H, 5000H are most often remakes from other ranges and their accuracy is problematic, i.e. you spend money and each insert measures differently.
Business is not sleeping
BIRD is a king, provided it is an original product, without interfering with the interior of the meter and especially the inserts
The Bird 43 wattmeter is a rugged, portable power meter with a practical way to change frequency and power ranges. Plugs are analog devices in which there is a certain dependence of indications in the function of the temperature which is not compensated. To ensure maximum repeatability, Bird 43 must be operated in an environment with very limited temperature, so-called. room temperature.
BIRD 43 has a very wide range of measured power and supported frequencies, its properties may interest us only when we reach the original, unprocessed and not repaired inserts, preferably not bruised. If we can obtain such a copy and especially inserts, then all its defects are of little importance. Many American radioamers have a BIRD 43 on their desk. In the US, this is an absolutely iconic meter, it must be in the vicinity of a power amplifier, eg KENWOOD TL-922, also cult classic.
The accuracy of the new power meter and the BIRD 43 reflectometer, including inserts, according to the manufacturer's declaration is not worse than 5%. My measurements indicate that on the original unprocessed slug, the error does not exceed 2% at the end of the scale. When the inserts are new, unused and not bruised, this accuracy is within 1%, it is difficult to see the error visually. Such accuracy should completely satisfy the radio amateur, unfortunately used, original inserts, without the interference of the "golden handle" are practically unavailable.
Due to the high price of these inserts, the EBAY auction site is dominated by a group of several repairers and you can buy what they will find out. If we buy from someone from the case, then usually he has previously bought an insert from one of these "traders", then disappointed resells it further and the wheel closes.
The BIRD 43 power meter fits with the tolerance declared by the manufacturer, the problem is that there are no such occasions to buy new inserts and relatively cheap.
Buying a good EBAY cartridge is a great lottery, if it is not very popular, the chances are good, but such inserts as 100H, 250H, 500H, 1000H, 2500H, 5000H are most often remakes from other ranges and their accuracy is problematic, i.e. you spend money and each insert measures differently.
Business is not sleeping
Bird has the official competitors, who have set up companies for this purpose and offer alternative, completely compatible gauges and inserts. One of the most popular companies is Coaxial Dynamics, which has its headquarters right under the nose BIRD ELEKTRONICS, also in Cleveland, maybe it was former BIRD employees ????
I have come across these inserts and I do not have a good opinion about them, very large parameters scattering, each shows something different. Fortunately, I was not tempted by the lower price of the new Coaxial Dynamics I bought old, used, more expensive, but original BIRD. My friend and known DX'men got acquainted with the quality problems of Coaxial Dynamics inserts, referred to the manufacturer and after a long negotiation procedure, exchanged for a new "precisely calibrated". The previous very low power, instead of 3KW indicated 2.4 KW, the current "accurately calibrated" only slightly undervalues, comparing to the used original the difference in the area of 10%.
Is it worth buying a BIRD?
I became a "happy" owner of 4 Birds and 15 inserts. At least a few of these slug falsyfikats or modifications, while several pieces work flawlessly. In order to achieve this, it was necessary to have something to compare with, and because I had nothing to compare with, I bought myself this "comparison" in the form of such a large number of meters.
Until recently, I lived in the belief that my BIRDs are accurate enough. If BIRDs were new and bought from the manufacturer or in the store, they would probably be very accurate. The problem is more about measuring inserts, because the accuracy of the power indication depends on them. If it were new, bought in a store and not the other hand, accuracy offered would be enough for my radio-amateur needs. Having several BIRDs and a dozen or so inserts, I had the opportunity to check that every gauge or insert is different. Of course, after the new original inserts, these are as accurate as possible.
Currently, I have inserts coming only from a reliable source, they have been withdrawn from the operation of the Ministry of Communications, exchanged for more modern measuring equipment. These pads are in perfect condition, look almost unused, are very accurate, measured errors are usually less than 2%.
Slug elements purchased on the EBAY auction portal are a lottery and everyone works as he wants, sometimes better, sometimes worse and sometimes not at all. Without a proven power standard, it is difficult to assess what they indicate. Because I have in my laboratory workshop - digital power meters, such as the Marconi 6960B or HP-437B, I am able to verify the accuracy of the indications of their Birds and cooperating with them. Thanks to this possibility, I was able to complete very precise BIRDS, including inserts.
There have been numerous meetings of several radio amateurs and we compared our BIRD and DAIWY. The only conclusions that could be drawn from such comparisons is that most of them pointed similarly but nevertheless each slightly different. Which of these measures was the closest to the truth? it was not like checking. Often the indicator of accuracy was the price of the meter, the more expensive the better. This was not always true, although there is usually such a relationship.
Model 43, which has been sold in more than 150,000 units since 1952. It consists basically of a 7/8-inch measuring line, two "quickly replaceable" connectors (there are many types of connectors available), die-cast housing. Buying a wattmeter is just the beginning of spending money: in fact, the meter will not be measuring until you buy one or more inserts, elements, corks or "snails" for the power levels and frequency ranges you are interested in.
The most common frequency ranges are:
"H": 2-30 MHz
"A": 25-60 MHz
"B": 50-125 MHz
"C": 100-250 MHz
"D": 200-500 MHz
"E": 400-1000 MHz
For each of the above ranges you can buy inserts with different powers for full scale, that is 5W, 10W, 25W, 50 W, 100 W, 250 W, 500 W, 1000 W. For the H range, more powerful 2500 W inserts are also available 5000 W. For example, the insert labeled "500H" is 500 W, 2-30 MHz.
The inserts usually work satisfactorily outside the range of frequencies specified by the manufacturer, the inserts work more widely, the more powerful the insert is.
The insert should be rotated to alternately measure the incident power and reflected power. In fact, you need to change inserts frequently, for example, an insert designed for power measurements in the range up to 2500 W may be suitable for measuring the incident power, but may not provide sufficient accuracy and resolution for measuring reflected power and insert a smaller insert to measure reflected power eg 500W and maybe even smaller. For this reason, there are also available measuring lines in which there are two sockets to place the inserts.
Despite the passage of years, prices do not want to fall, it is like wine, the older the better.
Best wishes
Tomasz sp5mxf.com
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