Multi-band radio

Discussion in 'Ham Radio Discussions' started by W7DGE, Apr 13, 2018.

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  1. AG6QR

    AG6QR Subscriber QRZ Page

    There is no certification for amateur radio equipment -- we operators are responsible for the technical details of our transceivers. So yes, it's perfectly legal for us to modify equipment designed for other services and use it on the Amateur Service. We can build our own radios from scratch, or using anything as a starting point, including a radio designed and sold for another service.

    The problem comes from the other direction. On GMRS, you must use a certificated transmitter, according to 95.129. A GMRS-Certificated transceiver must meet the requirements of Part 95, including 95.621, listing the frequencies permissible for GMRS operation. Part 95.655 specifically calls out that if the radio can transmit in the Amateur bands, it can't be certificated for GMRS.

    § 95.655 Frequency capability.

    (a) No transmitter will be certificated for use in the CB service if it is equipped with a frequency capability not listed in § 95.625, and no transmitter will be certificated for use in the GMRS if it is equipped with a frequency capability not listed in §95.621, unless such transmitter is also certificated for use in another radio service for which the frequency is authorized and for which certification is also required. (Transmitters with frequency capability for the Amateur Radio Services and Military Affiliate Radio System will not be certificated.)


    It's legal for us to to modify a GMRS-certified radio to use it on the Amateur Service, but if that's done, then it no longer meets the certification requirements for use on GMRS.
     
  2. KY5U

    KY5U Subscriber QRZ Page

    Yep, legal today to many hams is how do I read this rule that says I can't do what I want so that it lets me do what I want.
     
  3. AG6QR

    AG6QR Subscriber QRZ Page

    There are plenty of commercial (part 90) radios that can be programmed to work on Amateur frequencies. Part 90.203(e) requires that the radio not have the capability to change the frequency using front-panel controls, but it doesn't necessarily seem to prohibit "service and maintenance personnel" from programming a channel containing an amateur frequency.

    90.203(e) Except as provided in paragraph (g) of this section, transmitters designed to operate above 25 MHz shall not be certificated for use under this part if the operator can program and transmit on frequencies, other than those programmed by the manufacturer, service or maintenance personnel, using the equipment’s external operation controls.

    But the original question wasn't about using a radio on Part 90 commercial frequencies and Amateur frequencies. It was about GMRS and Amateur frequencies in the same radio. GMRS is governed by part 95, and that part has a specific clause that prohibits the use of radios capable of transmitting on the Amateur bands.
     
  4. AC0GT

    AC0GT Ham Member QRZ Page

    I did not mean to imply that there is a certification for Amateur radio, only that if a radio is advertised as an Amateur radio then it's not likely to be certified for use on any other bands. Doing some research on this I found that any radio sold commercially in the USA for use in the Amateur Radio Service will have to meet some FCC requirements, even if not specifically "certified" for some use or another. One example of such a requirement is that of Part 15 for use as a radio receiver, my Icom IC-207 has a Part 15 disclaimer on the bottom.

    Just FYI, the GMRS rules got rearranged, renumbered, and some rule changes made a few months ago. Searching for that section on current FCC rules leads nowhere.

    This is most likely still true, I just didn't find the current section on where that rule lies just yet.

    Here's one thing I found while reading about this, people have programmed Part 90 devices to operate on GMRS and Amateur frequencies and there's not much the FCC can do to stop it. It appears illegal to have a radio that operates on both Part 95 and Part 97, so I can't recommend programming a radio to do so. Where I've been lead astray is in running into a number of licensed Amateurs that have done Part 95 modifications. Some did so with the knowledge it was illegal (running more power than permitted for example) others doing so with the assumption it was legal (they met all technical requirements of a certificated device EXCEPT not transmitting on Amateur frequencies).

    So, let's go back to the original question....
    The answer is YES, such radios do exist. However, programming a radio to do so would violate FCC rules. What someone does with this information is best left unmentioned. Agreed?
     
    N2EY likes this.
  5. WA9SVD

    WA9SVD Ham Member QRZ Page

     
  6. WA9SVD

    WA9SVD Ham Member QRZ Page

    [QUOTE="AC0GT, post: 4627741, member: 220080"


    The answer is YES, such radios do exist. However, programming a radio to do so would violate FCC rules. What someone does with this information is best left unmentioned. Agreed?[/QUOTE]


    IF the radio is already certificated for Part 90, there is no problem with also programming them for Part 97 (Amateur) use, and does NOT violate FCC rules. Using AMATEUR (only) equipment on a frequency outside the Amateur allocations that require certificated equipment ( such as Part 90, Part 95) is illegal.
     
  7. AC0GT

    AC0GT Ham Member QRZ Page

    That appears to be true, but also not helpful to the question at hand. It's my fault for going down that Part 90 rabbit hole. I was mistaken on the legality of Part 90 radios on Part 95 frequencies.

    Yes, it's illegal. Is it possible? Yes, but also illegal.

    Here's the section on certification of GMRS radios I was looking for earlier.
    https://www.law.cornell.edu/cfr/text/47/95.1761

    No one will advertise a radio that will transmit on both Part 97 and Part 95 frequencies, because it would be illegal to operate a radio in this manner. We got into the territory of discussing Part 90 radios because I found out that there are many of them that can be programmed to operate on Amateur and GMRS frequencies, I was mistaken that this was legal to do. It does appear legal to have a radio that can operate under both Part 90 and Part 95, if certified for both. It appears to be legal (and I may be mistaken on this) to operate a radio under Part 90 and Part 97 if certified for Part 90. It's not legal to program a radio to transmit under both Part 95 and Part 97, that is prohibited explicitly.

    While looking at the Part 95 rules I discovered that the 155 mile limit on CB was removed. Not relevant here but interesting given the number of times I see this mentioned on QRZ.
     
    N2EY and AG6QR like this.
  8. KC8VWM

    KC8VWM Moderator Staff Member Volunteer Moderator QRZ Page

    It is legal to do. Just not at the same time.

    You can't operate a GMRS radio if it's equipped with frequencies outside the Part 95 band allocation.

    You CAN however operate an amateur radio with frequencies programmed outside the part 97 band allocation. (MARS, WX and GMRS receiving, but not transmitting etc.)
     
  9. AC0GT

    AC0GT Ham Member QRZ Page

    I thought about what this means in practice. The rules say the frequency determining controls must be internal. So, does that mean I have to pop open a door, push a button, and close the door, to switch between Amateur and GMRS frequencies? It seems a bit arbitrary and effectively meaningless at some point.

    Well, you can but it would be a violation of FCC rules to do so. That's like saying someone can't drive 72 MPH in a 70 MPH zone. Well, you can, I've done it. Will any law enforcement officer write a ticket for it? Not likely.

    I did some looking on the web for GMRS radios, just to see what these things cost and such, and found all kinds of discussion on what the rules mean and how to comply. Seems like GMRS radios are sometimes hard for people to obtain, but programming a Part 90 radio for GMRS is trivial. Does that break the rules? Some opinions are that it doesn't, because the radio would only transmit on GMRS and therefore meet the requirements of Part 95. Programming a Part 90 radio for frequencies within Part 95 AND Part 97 at the same time would be a violation, that's pretty clear.

    Sure, programming GMRS (and other services) frequencies into an Amateur radio for the purposes of receiving is pretty routine. I've done that myself. Bypassing the transmit lock-out in off the shelf Amateur radios is something different, that breaks some rules. Or, it at least gets into a gray area. A licensed Amateur with a radio capable of transmitting on GMRS is not likely to be a violation of the rules. The rules would be broken if that licensed Amateur transmitted on GMRS frequencies with that non-certified Amateur radio.

    I think we've gone well beyond answering the original question. I do enjoy discussing the nuance though.

    Oh, when it comes to things like MARS and CAP mods for Amateur radio transmitters I recall reading that this is discouraged now. The problem was that MARS and CAP had problems of poorly done mods on transmitters were producing poor quality output on the air. They want to see people using certified radios now. I guess that means Part 90, 87, and 80 radios programmed for MARS and CAP frequencies. I suppose that's something of a bummer for people, as it means buying more hardware. Or maybe it's an excuse to buy more hardware, as if anyone needs an excuse to buy more hardware. ;)
     
    KC8VWM likes this.
  10. KC8VWM

    KC8VWM Moderator Staff Member Volunteer Moderator QRZ Page

    Internal control in the sense that the end user cannot readily access any function to make any frequency adjustments using a key pad or other field operated control at their immediate disposal.
     
    Last edited: Apr 17, 2018 at 8:59 AM

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