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I have seen a number of innacurate statements about the LP-100 on various reflectors and web sites. Some of these I'm sure come about because of the unique design of the LP-100... unlike any previous wattmeter offered to the ham community. I hope none were intentionally misleading, although they were made by a competitor. Just to set the record straight, here are some paraphrased comments I have seen along with the facts about the LP-100 that should shed some light on the situation...

Coupler...

"Because the LP-100 uses RF connecting cables, it can't be remoted very far from the meter."

FACT: The coupler can be remoted up to about 50' using RG-58U cables and longer with larger cables. I have sold several LP-100s with 25' cables to guys with remotely located amplifiers. As long as the calibration is done with the long cables installed there will be no problem. In addition, the LP-100 design might actually be better for long runs between a remote amplifier on a different AC mains circuit, since it may be less susceptible to ground loops than a DC interfaced coupler.

There are many advantages to the LP-100 coupler design. The design does not use Fwd and Ref power samples. It senses current in the transmission line and voltage across the load. These are RF signals, which are terminated with 50 ohm attenuators, and then sent to the meter chassis with all level and phase information intact. In a typical coupler the I & V samples are combined to derive Fwd & Ref samples (whether rectified or not), and the level and phase information contained in the original samples is lost. In the LP-100, all calculations of Fwd and Ref power, SWR, vector impedance, etc., are carried out in the meter. There are several advantages of doing this, besides the obvious one of being able to measure vector impedance.

First, it allows me to measure the frequency of the signal, so that power corrections can be applied for each band instead of having to rely on the coupler being flat from 1.8 to 54 MHz using one setting. The LP-100 can be adjusted in 0.1% increments for each of the eleven bands.

Second, by not combining the I & V samples in the coupler, I have the luxury of being able to calibrate out parasitic coupling effects from the coupler... something you can't do when the samples are immediately connected together inside the coupler. This allows for some incredible directivity numbers... even on 6m.

BTW, I do offer N connectors as an option ($25).

Power rating...

"The LP-100 can't handle high power."

FACT: The LP-100 with standard coupler will handle 3,000W. In addition, I offer a number of high power couplers for 5,000W and 10,000W. The coupler type is selectable in one of the LP-100 setup screens. All scaling of the settings and display is automatically handled in the meter. My ratings are conservative. For example, my 10KW rating is for amateur service and duty cycles, but it will handle more power and run considerably cooler than my competitor's 10KW coupler, for which he claims a CCS (continuous) rating. I have heard from a guy who burned up a couple of his 10KW couplers at 5KW on 160m. The competitor's 10KW coupler appears to use the same cores as my 3KW, but has fewer turns on the transformers... meaning that it should handle less power than my 3KW.  I doubt that his coupler would handle his stated 10KW continuous power on any band below 30m.

One clear advantage of the LP-100 design for high power applications is the high resolution A/D converter... 4x higher than the competition's. The step size at 2500W is only 1.2W, and at 10KW is under 5W. This is almost 5x better than the competition's stated resolution at 10 kW.

Speed...

"Because the LP-100 has to do more calculations, it is slow."

FACT: With enough processing power, use of an optimized compiler and care in program design, more calculations are not an issue. The processor in the LP-100 is very fast (10 MIPS RISC processor, with single cycle hardware multiply). All the critical calculations take a total of less than 10 ms, and power is oversampled on top of that. The bargraphs in the LP-100 are refreshed over 100 times per second (100Hz). Compare that to the published spec of the competition (30 Hz), regardless of what casual claims they may make. It allows proper display of a single dit at well over 100 wpm, and amplifier tuning with a pulser is easy.

While we're on the subject, there are some other claims and comments that my competitor makes or has made about his product which I believe are misleading. I won't address those since I don't believe in negative advertising, except as required to defend my products. If you see a claim that doesn't ring true, feel free to email me for clarification.

There is one more comment I saw that I have to comment on.

"We are not a hobby business..."

FACT: I'm not sure what that means, but if is meant to imply that I am just pranking around in this business, then nothing could be further from the truth.

Our company, TelePost Inc., is over 21 years old. My wife and I had a very successful television post-production business for 16 years, but the ridiculous hours, deadlines and commitment got to be too intrusive. I had always wanted to manufacture ham equipment and we decided to make a change about 5 years ago. Our customers included many Fortune 500 companies, government agencies and even the Smithsonian Institution. We garnered dozens of national awards for our work. We were a national trend setter, with a million dollar operation and over a dozen employees. We intend to be in manufacturing of ham gear as well, and the success of the LP-100 is just the first indication of that. We also provided custom software to the Department of Homeland Security last year for an innovative new internet radio remote control emergency network.

By the way, it seems to me that a number of serious businesses were started by "hobbyists" like Art Collins, Bill Halligan, Bob Drake and other pioneers. Not to mention current "newcomers" like Elecraft, FlexRadio and SteppIR. In my opinion, the most innovative products seem to come from dedicated hams who are also good businessmen.

It appears to me that our chief competitive critic mostly markets electronic equipment that they either acquired, rep or act as a dealer for... not that they designed from scratch. It seems to me that the customer should be more comfortable with a company that designs their own equipment.

In closing, there is nothing secret about the LP-100 design as it is published for everyone to see in the assembly manual. If you have questions or concerns about something you read about my product on a reflector or competitor's web site, just email me for the facts. I will gladly give them to you. I will even recommend buying a competitor's meter if the most important thing to you is something his meter does better... like offering UHF couplers, rack mounting or analog meters for instance. As one customer recently posted on a popular reflector , "I have the Alpha, Array, and N8LP wattmeters since I'm the guy who needs to wear several wrist watches to know what time it is <g>.  All three are excellent.  There are some attributes of any one of them that I like above the others."

73,
Larry N8LP