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Wondering if someone makes a digital AM Transmitter allready assembled? Thought Ramsie did but they say they don’t make them assembled anymore. I am blind so it would be hard for me to assemble one.
Total posts : 45366You may not be aware that the FCC prohibits sale of assembled radio transmitters unless they are certified. Ramsey got into trouble a few years back over this which is why they won’t sell their units assembled.
AM transmitters are available assembled if they are certified. Some mentioned frequently on this forum are Rangemaster, Talking House, and Procaster. There are others though the names escape me at present but the key to getting one assembled is FCC certification.
Now and then AM transmitters, certified or not, are listed on web auction sites so this may be a way for you to acquire one.
Neil
Total posts : 45366FCC 15.25(b)…
“At least two units of the kit shall be assembled in exact accordance with the instructions supplied with the product to be marketed.”What is meant by “two units of the kit”?
Kits don’t require certification per sé, but do need to be registered to be in compliance with kit regulations. This seems to be yet another “grey area”. E.g., the SSTRAN comes with the IC pre-mounted and soldered in position, but how much of a kit can be pre-assembled before it can no longer be designated a kit?
… hoping Phil will chime in on this …OTOH, if you can come up with a top-notch circuit design you home-build yourself, you can own and operate up to 5 of them, so long as they meet the general Part 15 requirements, including the final stage 100mw input, 3m antenna/ground lead/transmission line length, of course the non-interference rule, and follow “good engineering practices”, a point to look at concerning that the FCC recognizes a home-builder may not have test equipment capable of rigorous compliance testing. IOW, what would they consider “good engineering” if the builder doesn’t have accurate test gear?
Total posts : 45366P.S. … OOOPS! So sorry Mr. Field Agent, my bad … I accidentally built my transmitter’s final input to be 100 watts instead of 100 milliwatts. … ;D
Total posts : 45366Ken,
This section refers to “TV interface device” kits rather than radio transmitter kits. Clear isn’t it?
Neil
Total posts : 45366Those of us who have had Amateur Radio licensees for a few years understand the application of the 2 unit kit rule. It was originally put in place to keep folks from “manufacturing” large amplifiers for other than their own, and close friends, use. There were, in years past, folks who designed and built high output 4-1000 tube type amplifiers that would easily make a couple of kilowatts output. And by the way, once they are built and been operated for a short period of time for personal use, there is no law or rule that says you can’t sell the completed device (one at a time).
The term “pecuniary interest” enters here as well; a very important component of Part 97. “Personal enrichment” (Part 73) is another way of saying it. The FCC, in recent years, has issued many of its rules by concentrating on the phrase, “Follow the money.” By controlling the marketing of transmitter kits, the FCC can control the proliferation of the finished units out in the world. Plus, the limit of five(5) kits of “self design” allowed to be built each year allows for proto-typing operating units for testing and keep the lid on the spread of units that are potentially cross ways with the rules at some point, The whole point of the rules is CONTROL.
Nearly all parts of the FCC rules and regulations are moving targets, flexing and bending to the demand put on them by innovation and demand for technology. Since 1934, very little has changed in that philosophy of the FCC and the Federal government; even though the substance and application has gone through constant change.
I am constantly entertained by folks who are critical of circumstances (brought on by rules, regulations and laws) that are counter to their purposes, right or wrong. A sense of history and an intellectual understanding the totality of the rules is essential in being credibly critical. Otherwise, If you examine a dead horse at length, does it ever gain life authentically, ever? The rules are the rules folks. If you can find the day-light to operate in a new and creative way and convince the inspector you are not breaking the letter and spirit of the rules, rock on.
If you read the rules today and expect them to have the same meaning, and be applied the same a year or two from now, you might have something other than tobacco in your pipe. 😉
Total posts : 45366Well, here’s one long time licensed amateur who doesn’t understand the 2 unit kit rule. In fact, I never heard of it so a cite would help me.
Also, my last reading of the rules revealed that amateur radio equipment was exempt from the certification requirement. With this in mind what would be the difference between me building some units for myself and others (friends or not) contrasted with me establishing a manufacturing company to do the same thing? Are Kenwood , ICOM, et. al. restricted?
There was some clamping down during the CB craze in the 70s such as prohibiting the manufacture of amplifiers which would operate in the 11 meter band. As I recall, some manufacturers (Drake for example) provided a tap on the tuning coil so the amateur could wire it for 10 meter operation.
Neil
Total posts : 45366Darn … I’m afraid I don’t have your perspective (nor am I ever likely to), so I thought I was being humorous … but, I guess not. I don’t want to resurrect a horse … maybe just a mouse …. 😉
I haven’t seen much discussion so the questions remain, but I’ll try to clarify, albeit perhaps sophomoric. Given the current understanding of the rules:
1) How much of a part 15 compliant kit can come pre-assembled?
2) What is expected for good engineering practices involving the accuracy of testing home-built Part 15 compliant transmitters?
I don’t smoke … but I’m not entirely sure a lack of understanding of the moving target machinations of government agencies is tantamount to … aw, never mind … 😉
Total posts : 45366Amateur kit limitations only apply to amplifiers and none have ever required “certification”. However, amplifier kits capable of being used above 25 MHz are prohibited from sale in the U.S. and its territories without the presentation of a valid FCC license. Each amp kit built is still subject to the rules regarding signal purity, bandwidth of signal, out of band radiation and harmonic interference. Transmitter or transceiver kits have no limitation for personal use.
If, as an Amateur you were to build five amps or transmitters and give them to friends at no charge; no problem. Ham clubs do that all the time. And, yes, all commercial manufacturers of transmitting equipment are required to have equipment sold in the U.S., certified or type accepted. MFJ, Drake, Vectronics and others provide taps to operate their amplifiers on the 12 and 10 meter bands (above 25 MHz). But because of FCC regulations, manufacturers require the presentation of a valid FCC license before the tuned components for the amp are shipped with the unit for modification and operation above 25 MHz. This is done to simply cover ones posterior.
In the recent past, Pilot Travel Centers were taken to court and fined severely for selling ham equipment to non-licensed buyers. The equipment operated on ham frequencies and could easily be changed to operate on the CB band as well. In a separate case, intentional radiators made overseas have been marketed in the U.S. recently in Florida. The FCC included the lack of type acceptance and certification, as well as signal purity and out of band interference, in the legal citation. Believe it or not, they were also marketed as cell phone jamming units. Because the seller was outside of the U.S., the users were the proud recipients of the NOV.
Good engineering practice is generally accepted to be the customary care taken in construction technique and practice, along with operating practices, to ensure a device that operates within the signal parameters set out as minimums in the rules. If the device interferes with other services or licensees, for any reason, good engineering practice is said to NOT be in use.
And finally, in the case of the Part 15 transmitter kit with some of the surface mount components soldered to the motherboard, the board and the attached components are considered a single piece. Without the other parts, the unit will not function. So, the kit is considered still a kit by the FCC. Otherwise, the purist could point out that an integrated circuit chip is actually several different components in a common case. And as such, could not be built into a kit at any point prior becoming a functional piece of equipment. In this day and age, that would be considered nuts. Right?
Give me a minute. I’ll be right back after throwing some dirt on my horse. I’m trying to protect the environment. 😉
Total posts : 45366“Also, my last reading of the rules revealed that amateur radio equipment was exempt from the certification requirement.”
Hmmmmm. The new TenTec Eagle was held up until the FCC issued a “Grant” so they could sell it.
It could be that they are required to have “type acceptance” rather than certification. I have read some conflicting information re this.
Since I am not a manufacturer nor is this an amateur radio board I am going to abandon this topic with the advisory that if someone is really interested they need to read the FCC rules. I am not interested in pursuing it.
Neil
Total posts : 45366commercially built ham radios require part 15 type acceptance and the rules regarding linears above 25 mhz has been dropped.
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