Transmit mods for ham radios are generally for one legitimate purpose; using the radio for the Military Auxiliary Radio Service (AKA MARS). It is not legal to use such mods for any other purpose.
Why is out of band transmit illegal? (was: Stupid question)
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Transmit mods for ham radios are generally for one legitimate purpose; using the radio for the Military Auxiliary Radio Service (AKA MARS). It is not legal to use such mods for any other purpose.
My question is, why is this thread still going? The opening title was completely ridiculous and probably meant to stir up trouble, which it did, but its still going 12 pages later.
prcguy
prcguy
Because it can?
I can only speak for myself... Sometimes it's hard to resist a good debate. I certainly have no illusions that anyone's mind will be changed.
N8IAA
Member
Is there still VHF MARS? I know that one can't use a modded 2m radio for CAP anymore.
Just wondering,
Larry
As far as I know, yes. Army and Air Force MARS still exist, but Navy/Marine Corps MARS is being phased out this year.
The primary purpose is for the factory to be able to modify the transmit frequencies based on the location that the radios are being shipped to. Not all countries use the same spectrum allocations as the US, such as Cuba that is only 144-146MHz in VHF. That is the real reason for the ability to shift the TX capabilities of these radios with a simple modification.
The information eventually gets out into the public domain and the owner takes it upon himself, in every case voiding the original warranty, and modifies the TX capabilities even though the radio might not be not certificated for other areas of the spectrum.
MARS has had a specific listing on what radios are allowed or quite some time and I could find no amateur grade radios of the major manufacturers approved for usage: https://comm.capnhq.gov/equipment/equipment.cfm
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Actually, you linked the CAP authorized equipment list.
Is there a similar list for MARS?
Is there anywhere in the U.S. where MARS operates on VHF/UHF?
Yup your right...my bad as I meant to put in CAP. But they both (MARS and CAP) use government frequencies managed by NTIA and not the FCC so one would think that the equipment list would be very similar, if not identical.
Hard to say if they are still in operation in VHF, but it looks like this unofficial webpage says that they once were. USAF MARS North Central Division VHF Directory
This web site is not an official USA, USAF or DOD function. It is privately maintained by and for volunteer MARS Affiliates members. It is intended to serve as an information source and to provide guidance for USAF MARS members who wish to implement digital capabilities for their station. Reference to any commercial product does not constitute an endorsement of that product by the DOD, USAF or USAF MARS.
It's my understanding that since you have to be a ham to be eligible for a standard MARS license, they have allowed commercially manufactured Ham equipment to be used, so you weren't required to spend additional funds beyond what you already had.
rapidcharger
Member
I will be happy to post my letter and the response I get, when and if I get a response and if this thread is still open for posting.
Until that time I will be in lurk mode and not posting any further replies to this thread. Thank you for your interest.
Sent from my iPad Air using The Uncarrier.
nd5y
Member
I was in AF MARS in the mid to late 90s. Back then each service branch had one or two VHF repeater pairs and simplex channels of their own allocated nationwide. Sometime after I quit they allowed each branch to use all of the frequencies. Some areas also had local or regional allocations. Most (maybe all) military bases and most larger cities had MARS repeaters. Sometime around 10 or 15 years ago so they allowed all branches access to all of the VHF frequencies. When I was active that wasn't the case unelss you had special permission.
After I quit in the late 90's the government narrowbanded and reconfigured the 138-150.8 government bands plan and changed some of the MARS frequencies. I haven't kept up with them and I don't know what the current MARS allocations are. I suppose MARS is now subject to NTIA narrowband requirements like CAP so they don't interfere with other government users on adjacent channels.
I was never aware of any UHF or low band frequencies. Those were probably locally allocated.
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ecps92
Member
ecps92
Member
Nope, each ran different Policies. Altho all 3 (CAP, MARS and CG Aux) are manged by NTIA, The only one let (I could be wrong) is MARS for modified radios, all the others have gone Narrowband. And as I think about it MARS had only grandfathered radios, but if that died or got transferred it was No Longer grandfathered.
WB8TCR
Member
Interesting thread. I hope you do receive a response and look forward to reading it.
I've had a General license since the early '70s, though was inactive for a long time until recently. I remember learning the rule in question then and always thought it was indeed band non-specific, largely placed there for a catastrophic distress situation, allowing maybe the only person with communication and electronic skills present to get a distress call out to save life and limb. For a wild example, a plane crash in the Pacific Northwest or shipwreck in a desolate area, carping together a spark gap transmitter, etc. I believe this is a very old rule, formulated at a time very different from the present. I never envisioned self-appointed Rambos/wannabees with cheap programmable HTs busting into LE frequencies as the example in question and see why this discussion took the course it did. I doubt the FCC did either back then.
I'll have to Google and familiarize myself with the case mentioned earlier. IANAL but know that depending on the particular court system, it may or may not apply as precedent to other courts in other jurisdictions. I certainly back the FCC's zeal to protect the purity of band plans and pursue illegal transmissions. That said, count me in as somebody who would pursue (almost) any means at my disposal in an extreme and dire situation. I like to be prepared for situations I might find myself and avoid ones I should, though it would be unrealistic to believe one could never be confronted with a situation they were thrust into and unprepared for. It's an odds game, so stack the deck as best you can for yourself, no doubt.
rapidcharger
Member
Still haven't RXd a reply yet. I will swing by the POB today and see.
I agree, the language isn't specific enough and should be re-written if it doesn't mean what it says.
Token
Member
I know my point here is not what this thread is about, but I will strongly disagree with the last part of the above statement, "It is not legal to use such mods for any other purpose". I have used MARS / CAP mods for legal purposes, and not in support of MARS or CAP.
When working with transverters it is sometimes very nice / convenient to be able to use the transceiver / exciter outside the normal ham bands. Of course most commercially available transverters are configured to work with transceivers / exciters that are constrained to the allocated ham bands, but when home brewing being able to use the transceiver on other freqs opens up the possibilities for LOs, filters, etc. This makes building from the junk box much easier.
T!
k6cpo
Member
That list is horribly out of date, at least for Yaesu. Perhaps that's just as well as we shouldn't be encouraging modifying radios for out-of-band transmit.
I get what you're saying, and yes, that is a valid use of such a mod as long as you take the precautions needed to make sure you're not radiating a significant amount of RF on those frequencies.
mmckenna
I ♥ Ø
A good point, however the issue with that is that the rule is in Part 97. If it was intended for emergencies and for anyone to use, it would be under Part 2, maybe somewhere else. Since it is specifically mentioned under Part 97, that is where many of us believe it only applies. If it was meant to apply under different services (part 80, part 90, part 95) then the FCC could have put a similar rule under those parts.
If you do look into Part 2, there is a rule regarding this, and it's quite specific.
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