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Frequently Asked Questions

Why do I need tested RF cables? 

In order to test RF equipment to manufacturer’s specifications, you must take into account your test cable losses. Just 0.5 dB of cable loss will affect your measurement by about 12%. If you’re testing a transmitter that has a ±10% output power specification, that 0.5 dB of unaccounted for cable loss makes it impossible to determine if that transmitter is operating properly. You MUST know and take into account the actual cable loss in your measurement. A test cable with known losses will allow you to make the proper measurements and adjustments to your RF equipment. Make your equipment perform better and last longer by ensuring you correctly test and align it.

 

Our Field Service Grade RF Test Cables start with having a proper design. You know what your test cables have to survive; repeated on/off cycling, constant flexing, being stepped on, and then thrown into a tool box. Everything about our cables is thought out and specified to ensure inherent ruggedness and repeatability. Our cables are then manufactured to exacting specifications. Every one of our cables is completely tested for both mechanical and electrical performance. Your cable is individually serialized, provided with traceable test data, and delivered with protective packaging to ensure your investment continues to meet the high expectations you have.

 

Why are the mechanical characteristics important? 

While we think of cables and connectors in terms of their electrical characteristics and performance, they are in reality precision mechanical devices. In other words, the electrical properties we desire depend mostly upon mechanical properties such as dimension and density. Since connectors are really a physical interface, their proper operation depends upon meeting certain physical characteristics.

 

The most important dimensions are the center conductor outer diameter, the outer conductor inner diameter, and the pin depth. For newly installed connectors, the most important parameter to measure is the pin depth. Manufacturers do a good job of delivering connectors with the proper diameters and our precision TDR test would reveal any issues in this regard. The pin depth, however, is dependant upon the connector assembly process. So, we always measure the pin depth and ensure it is within acceptable limits. It should be noted that an incorrect pin depth can cause damage to mating connectors or lead to intermittent/inconsistent connections.

 

Why shouldn't my field engineers and technicians build their own cables? 

First and foremost, having your technical staff spend time with this is expensive. Wouldn't you rather have them out generating revenue or otherwise focused on their core competencies?

 

Secondly, very few technical operations have the knowledge, experience, and equipment to build a truly reliable and consistent field RF test cable in an efficient manner. We have spent considerable time and money to design, engineer, and manufacture the proper test cables. We have the correct test equipment to completely and accurately test our cables. This ensures your technical staff can make reliable field RF measurements, every time.

 

What other value do your cables provide? 

By using color coded cables in a consistent fashion, you may be able to prevent damage to the RF equipment or to your test equipment. What happens when you connect a transmitter to your Communication Analyzer's generate port? You're likely to damage your Communication Analyzer and end up with an expensive repair bill! By using a consistent color code for transmit verses receiver test cables we can help you minimize the potential for equipment damage.

 

An additional advantage to using test cables with known loss is that you can use a cable length that makes your testing easier to setup and faster. To minimize cable loss, many people will use the shortest cable possible. This often leads to less than ideal working conditions. With out test cables you can make your setup more user friendly and still make accurate measurements.

 

Are your cables Phase Stable? 

Our Field Service Grade test cables are not designed for phase stability. However, at LMR frequencies (up to 1 GHz) our test cables are adequate for use with Antenna Testers or Network Analyzers for tasks such as combiner tuning or filter sweeping. These tasks are generally limited to a Return Loss on the order of 20 dB. If you are testing a hard line cable and making measurements in the 50 dB Return Loss range these cables are not suitable for this purpose.

 

Why do some manufacturers advertise a 175 lb. pull test force and yours are only 25 lbs? 

A 25 lb. retention force is quite adequate for the field. Our cables are tested with this weight (which is more substantial than you might think) but can actually typically withstand 2x this pull force. The reason we do not manufacture our cables for a higher pull force is that we would rather have you damage a $100 cable instead of a $15K+ piece of test equipment when you are out in the field. If I trip over a test cable on site I would much rather deal with a cable issue than have that cable so strong that it pulls my test equipment off a shelf or table and onto the floor!

 

Why don't you use LMR style coax cable? 

In a nutshell, this is not the best overall cable for field service use. It's great for a lot of purposes but there are better cable choices for field service applications. Some of the items of concern are the foam dielectric, solid bare copper center conductor, and the tinned copper shield braid. This cable construction tends to exhibit higher insertion loss ripple with frequency.