220 Mhz

Discussion in 'General Technical Questions and Answers' started by KE5MLF, May 3, 2007.

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  1. KE5MLF

    KE5MLF Ham Member QRZ Page

    I am a new tech and was wondering why we lost 220-222? I was given a repeater in that range... There are no repeaters on 1.25 in this area.... I am sure you can see where I am going with this.. Whats your opinion in leaving this repeater operational? I probably would be better starting over... So I really don't know why I am asking this question..
     
  2. KD7MSC

    KD7MSC Ham Member QRZ Page

    Put it on a 222 -225MHz repeater pair.?
     
  3. KC0W

    KC0W Premium Subscriber QRZ Page

    We have UPS to thank for this.


    Tom kcØw
     
  4. WA9SVD

    WA9SVD Ham Member QRZ Page

    The 220 MHz band is only an Amateur allocation in ITU Region II, (basically, North and South America.) The FCC decided (was convinced) that 220-222 MHz would be best served in the Land Mobile Service, by a petition of UPS to use ACSSB (Amplitude-Compandered Single Side Band.)
    That system never worked out well for UPS, and has been abandoned.

    The only use for the repeater you have is to obtain a frequency pair from your coordination organization, and retune it to an assigned frequency in the 222-225 MHz band. Obviously, it wouldn't be legal (or usable) "as is." The ability to retune may or may not be possible without extensive modification of the filters (typically cavity filters) which have to be very accurately tuned for proper operation.
    If there are few repeaters in your area, there should be little problem in obtaining a coordinated frequency pair. But by the same token, if there are few users interested, the expense of installing and maintaining a repeater may be yours alone. That can be more than you think.
    Good luck.
     
  5. N4CD

    N4CD Ham Member QRZ Page

    We lost 220-222 because business interests convinced the FCC there was hundreds of millions of dollars of new business there if the FCC allocated it to 'two way radio' like at 150-170 MHz, 30-50 MHz, and 450-512 MHz.

    Unfortunately, the technology was poor - ACSB on 5 KHz channels - that never worked well from day one. It was not viable, the equipment was only made by one or two manufacturer's, and the emergence of systems like Nextel with group calling ability made it uncompetitive. It was an 'orphan technology' from day one - and it went back to the 1970s when 'trunking systems' at 800 MHz were a big hit (and big financial success). The company that came up with 220-222 ACSB thought they could immitate the success.

    Unfortunately, it was the wrong frequency (poor re-use), the wrong technology (sounded not great), and no one was interested in it. (llike paying customers). The big bonanza didn't happen.

    Sort of like BPL....sold for all the wrong reasons to the FCC. Not viable in nearly all cases for 'broadband access' to the home. It was a technology invented to make money for the manufacturers - but there were few customers who could make money with it after they examined the economics.

    In certain regions of the country, there is a fair amount of FM actiivity on 222-225 MHz - but few mobiles/handhelds cover that freq range, so equipment tends to cost more.

    Of course, 11 meters was once a ham band, until manufacturers convinced the FCC there was a bazillion bucks to be made. Unfortunately,within a few years, all the equipment was made overseas, and it was those folks there that made the gazillion bucks selling us cheap CB stuff.
     
  6. KL7AJ

    KL7AJ Ham Member QRZ Page

    It was one of those catch-22's. The band segment was given away because nobody was on it. Nobody was on it because nobody was making equipment for it. Nobody was making equipment for it, because nobody was using it.

    Best case for homebrewing I've ever heard.

    eric
     
  7. WA7KKP

    WA7KKP Ham Member QRZ Page

    United Parcel Service "bought" that spectrum, and was going to have a nationwide data/voice network using ACSSB.

    Turned out to not be feasable, and have done nothing with it.

    if you were assigned a pair in the bottom 2 MHz, someone wasn't doing their homework.

    Gary WA7KKP
     
  8. WA7KKP

    WA7KKP Ham Member QRZ Page

    Who builds anything from scratch?

    The popularity of 10/6/2/440 FM is due to the simple fact that cheap surplus equipment was available in the 60's and 70's . . . castoffs from the Public Service Bands.

    And we won't mention that 220 MHz is only a ham band in North America, thus limiting demand even further. That's why only a few manufacturers build equipment.

    Gary WA7KKP
     
  9. K9STH

    K9STH Platinum Subscriber Volunteer Moderator Platinum Subscriber QRZ Page

    ACSB (amplitude companded sideband) is a very viable mode. However, it is not compatible with other modes and generally has not become popular. One problem is that when a repeater is used the audio is processed no less than 16 times (4 in the originating transmitter, 4 in the repeater receiver, 4 in the repeater transmitter, and 4 in the final receiver). The result is that virtually all of the identification qualities that occurs in the human voice are removed. The audio quality is normally very good. However, everyone "sounds" the same!

    ACSB is more expensive to build. That is, the equipment is considerably more complex than FM or AM.

    When United Parcel Service was petitioning the FCC for the 220 MHz to 222 MHz segment their proposal was to use "narrow band" technology of which ACSB is one of the best. The FCC accepted this reasoning and when they removed amateur radio from that 2 MHz segment and allowed land mobile (which the band is actually for) to use the frequencies. However, wider modes like AM or FM were prohibited.

    Just as soon as UPS got the rules modified they immediately tried to get "normal" +/- 5 KHz deviation FM allowed because they (UPS) did not want to have to spend the additional funds for ACSB equipment. It is in the FCC's favor that the original rules were not modified to allow FM operation in the 220 MHz to 222 MHz range. The result was that UPS, after a very small prototype operation, abandoned the 220 MHz to 222 MHz band and went to a 900 MHz trunking system.

    There are a few commercial two-way operations operating using ACSB in the 220 MHz to 222 MHz segment. However, the commercial operation is just as sparse as amateur radio operation in the 222 MHz to 225 MHz range.

    When I went to work for Texas Utilities (now TXU), the electric company for about half the State of Texas, in 1989 they had decided on a highband (150.8 MHz to 174 MHz) ACSB system for use in over half the State of Texas. I recommended against this system. Now it was not the technology, because that worked fine. It was because there were only 2 manufacturers of ACSB equipment (SEA and Aerotron) and I was not comfortable with either manufacturer. I was informed that the "higher ups" had made the decision to use ACSB and that I would have to "live with the situation".

    We acquired like 75 repeaters and about 1500 mobile units. Of these about 30 repeaters were installed and the remainder waited to expand the system. I had about 120 mobile units in service in the Midland / Odessa area and about 100 in service in Wichita Falls. The repeaters and mobile units were manufactured by Aerotron and the portable units by SEA. The reliability of the repeater stations and the control stations was excellent. However, these were crystal controlled stations. The reliability of the mobile stations (these were synthesized frequency units), especially during the Texas summer, was dismal! I had to pull over 400 mobile units from the "stock" that was intended to be used at other locations to use as "spares" for both major locations that used the equipment. This was an approximate ratio of 2 spares for each mobile unit.

    There was a person in Lake Jackson, Texas, who was probably the most qualified person in the entire United States to repair ACSB equipment. I would make quarterly trips from Dallas to Wichita Falls and then down to Lake Jackson (which is about 60 miles southwest of Houston a couple of miles from the Gulf of Mexico). I generally had about 60 mobile units to be repaired and picked up a like number of units which had been repaired. Then it was back to Wichita Falls and then back to Dallas. Every 4 or 5 months I would make the same trip but from Dallas to Odessa then to Lake Jackson then to Odessa and finally back to Dallas.

    Finally, TXU abandoned the ACSB system and went to a 900 MHz trunking system. When all was said and done, I had to sell off not only about 700 used mobile ASCB units but about 800 that were still brand new in unopened boxes! I also had about 45 repeater stations that were brand new in unopened boxes as well as about 30 repeaters that had been removed from service.

    The TXU Amateur Radio Club obtained a number of the mobile ACSB units and a few repeaters for use on the 2 meter band (ACSB is PERFECTLY legal for use by amateur radio operators). The idea was to put a couple of repeaters on the top of the downtown Dallas corporate headquarters building (47 stories high) and use the mobiles. However, the repeaters were never put in place although quite a number of employees who held amateur radio operators' licenses did use the ACSB mobiles on the 2 meter band.

    Also, since TXU had a VERY extensive microwave system it was eventually planned to install ACSB repeaters in the major cities in Texas that were served by TXU and have all of the repeaters "linked".

    We also had a few SEA dashmount units (the Aerotron units were trunk mount) that we had acquired to "check out". These were never put in operation on the TXU system. I have a couple of these brand new in the original box that I acquired to use with the 2 meter system.

    Now UPS was instrumental in amateur radio operators losing the 220 MHz to 222 MHz band and when they didn't get their way to use FM units instead of ACSB UPS went to a trunking system using FM in the "normal" two-way bands.

    However, ACSB is definitely a well working mode. A 25 watt PEP mobile is just as good as, and in some cases better than, a 100 watt FM mobile in performance. Unfortunately, the cost of producing ACSB is considerably more than FM and the result is that there has not been a widespread acceptance of the mode. Then there is the fact that ACSB is not even closely compatible to AM, FM, SSB, or any other generally accepted method of communication.

    Added on edit: The 222 MHz band is available in Region II which is North and South America, not just North America.

    Glen, K9STH
     
  10. N4CD

    N4CD Ham Member QRZ Page

    ACSB was a 'technology solution' looking for a customer to get it going. The FCC is always 'enamored' of claims of 'spectrum efficiency' and a 'demonstration' of the technology. Same thing for BPL - another technology looking for a customer.


    I was working for GE Mobile systems back then. GE looked seriously at the technology. It was horrible sounding and more complicated. It did not have any of the features of the new trunking systems and didn't have low cost mobiles and handheld/portable units.

    The supposed 'spectrum efficiency' didn't appear to be there either. It was very debatable if it had any better/worse than narrow-band FM.

    Thanks for the first hand report of TXU. Too bad they got suckered into a management decision. Looks like they too were blinded by 'technology dazzle'.

    In the field of radio technology, you don't want to be on the 'bleeding edge' because it often will be exactly that.

    I don't even know if Aerotron and SEA are still around. None of the major manufacturers were the least bit interested in making the equipment (GE, Motorola), and the technology was further hindered by claims of 'patented technology' which would have required hefty patent royalties. Or for the others, or possibly not at all since those two saw big dollar signs in making all the equipment themselves.

    Just like BPL, where trial systems are being fielded then abandoned as fast as possible it seems, there may be no market for a technology 'invented' to supposedly fill a market that in reality doesn't exist at too high a price and too poor a performance level (interference). Too much 'dazzle' and very little benefit in the end.

    The little LEO (low earth orbiting satellites ) keep eying part of the ham 2m band......again hoping to convince the FCC that 'this technology' will provide all sorts of benefits to everyone. IT has gone no where for 30 years, but someone keeps foisting it up on FCC wanting 'spectrum' for it.

    The FCC is in the 'business' of 'creating' more business opportunities.

    Satellite radio (one of the two operators will likely fail)....

    Satellite TV - there were supposed to be three competitors...at the current rate - only two ever got operational - there will be one in 10 years.

    The FCC has a poor record of picking winners. The incumbents also have a large interest in keeping things status quo.
     
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