27mhz or 75mhz, why the diffrence?
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27mhz or 75mhz, why the diffrence?
OK, sorry if this has been beat to death at some point, just trying to understand something here. I have a stadium truck with the Futaba 27mhz magnum radio. One of my coworkers has a savage with a 75mhz digital type. The two are seemigly the same except for brand diffrences and both controllers will allow us to drive the htings out farther than we can see well enough to control. Our courisity was as to why the two diffrent bands? His cost more and we're assuming it is better, but can't really figure out how. So, my question for you guys here is: What are the major diffrences between the two? Which is better and in what ways?
Thanks in advance for your help,
George
Thanks in advance for your help,
George
#2
RE: 27mhz or 75mhz, why the diffrence?
75Mhz has more available frequencies.
27Mhz
Number Frequency Color
1 26.995 Brown
2 27.045 Red
3 27.095 Orange
4 27.145 Yellow
5 27.195 Green
6 27.255 Blue
75Mhz
Channel Frequency
61 75.410 | 76 75.710
62 75.430 | 77 75.730
63 75.450 | 78 75.750
64 75.470 | 79 75.770
65 75.490 | 80 75.790
66 75.510 | 81 75.810
67 75.530 | 82 75.830
68 75.550 | 83 75.850
69 75.570 | 84 75.870
70 75.590 | 85 75.890
71 75.610 | 86 75.910
72 75.630 | 87 75.930
73 75.650 | 88 75.950
74 75.670 | 89 75.970
75 75.690 | 90 75.990
27Mhz
Number Frequency Color
1 26.995 Brown
2 27.045 Red
3 27.095 Orange
4 27.145 Yellow
5 27.195 Green
6 27.255 Blue
75Mhz
Channel Frequency
61 75.410 | 76 75.710
62 75.430 | 77 75.730
63 75.450 | 78 75.750
64 75.470 | 79 75.770
65 75.490 | 80 75.790
66 75.510 | 81 75.810
67 75.530 | 82 75.830
68 75.550 | 83 75.850
69 75.570 | 84 75.870
70 75.590 | 85 75.890
71 75.610 | 86 75.910
72 75.630 | 87 75.930
73 75.650 | 88 75.950
74 75.670 | 89 75.970
75 75.690 | 90 75.990
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RE: 27mhz or 75mhz, why the diffrence?
In simple terms...
27mhz is AM
75mhz is FM
If you have a car radio that is AM/FM - find an AM station that comes in and then drive near some of those high voltage power lines.
27mhz is AM
75mhz is FM
If you have a car radio that is AM/FM - find an AM station that comes in and then drive near some of those high voltage power lines.
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RE: 27mhz or 75mhz, why the diffrence?
Thanks for clearing this up for me. We couldn't seem to find anything that his did better, and neither of us race so the avaliability of more channels doesn't really matter at al.
Thanks,
George
Thanks,
George
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RE: 27mhz or 75mhz, why the diffrence?
There is a big misconception that all 75mhz radios are FM, which is untrue. 27 and 75 are available in both am and fm modulation. The FCC sets limits on frequency designation's here is an excerpt from FCC.gov concerning RC frequencies.
Something else interesting about 27mhz......
[link]http://a257.g.akamaitech.net/7/257/2422/05dec20031700/
edocket.access.gpo.gov/cfr_2003/octqtr/47cfr95.207.htm[/link]
NG56 In the bands 72.0-73.0 and 75.4-76.0 MHz, the use of mobile
radio remote control of models is on a secondary basis to all other
fixed and mobile operations. Such operations are subject to the
condition that interference will not be caused to common carrier
domestic public stations, to remote control of industrial equipment
operating in the 72-76 MHz band, or to the reception of television
signal on channels 4 (66-72 MHz) or 5 (76-82 MHz). Television
interference shall be considered to occur whenever reception of
regularly used television signals is impaired or destroyed, regardless
of the strength of the television signal or the distance to the
television station.
radio remote control of models is on a secondary basis to all other
fixed and mobile operations. Such operations are subject to the
condition that interference will not be caused to common carrier
domestic public stations, to remote control of industrial equipment
operating in the 72-76 MHz band, or to the reception of television
signal on channels 4 (66-72 MHz) or 5 (76-82 MHz). Television
interference shall be considered to occur whenever reception of
regularly used television signals is impaired or destroyed, regardless
of the strength of the television signal or the distance to the
television station.
(e) Non-Federal services operating on frequencies in the band 25-50
MHz must recognize that it is shared with various services of other
countries; that harmful interference may be caused by skywave signals
received from distant stations of all services of the United States and
other countries radiating power on frequencies in this band; and that no
protection from such harmful interference generally can be expected.
Persons desiring to avoid such harmful interference should consider
operation on available frequencies higher in the radio spectrum not
generally subject to this type of difficulty.
MHz must recognize that it is shared with various services of other
countries; that harmful interference may be caused by skywave signals
received from distant stations of all services of the United States and
other countries radiating power on frequencies in this band; and that no
protection from such harmful interference generally can be expected.
Persons desiring to avoid such harmful interference should consider
operation on available frequencies higher in the radio spectrum not
generally subject to this type of difficulty.
edocket.access.gpo.gov/cfr_2003/octqtr/47cfr95.207.htm[/link]
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RE: 27mhz or 75mhz, why the diffrence?
Breaker Breaker One-Nine, got a smokey report for the next county???
27 MHz fell out of favor very quickly after the 75 MHz channels were allowed because of the limited number of channels on 27 and CB radio was going big time. While the FCC limited the input on CB radios to 5 watts many folks installed amps on the output boosting it to 25 to over 1,000 watts. While it worked for them it tended to spread the signal they output over many adjacent channels including the 6 allotted for RC. While the problem has not gone totally away there is less use of the CB radios and I think their equipment has gotten better.
Ed M.
27 MHz fell out of favor very quickly after the 75 MHz channels were allowed because of the limited number of channels on 27 and CB radio was going big time. While the FCC limited the input on CB radios to 5 watts many folks installed amps on the output boosting it to 25 to over 1,000 watts. While it worked for them it tended to spread the signal they output over many adjacent channels including the 6 allotted for RC. While the problem has not gone totally away there is less use of the CB radios and I think their equipment has gotten better.
Ed M.
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RE: 27mhz or 75mhz, why the diffrence?
There is no differance in 27 and 75.
Is one am and the other fm?
Another reason for his costing more could be options/Settings.
Is one am and the other fm?
Another reason for his costing more could be options/Settings.
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RE: 27mhz or 75mhz, why the diffrence?
The frequency of the signal remains the same regardless of the type of modulation (AM or FM). The price is just features and quality, some manufacturers use filters to reduce interference. There is a difference between the two types of modulation, entire books have been written so I am not going to get into that but FM is generally the better of the two.
#13
RE: 27mhz or 75mhz, why the diffrence?
I'm not able to take the 2.4 ghz leap yet, thanks to a new business and new baby daughter keeping my wallet light, so I've been trying to track down some new receivers to work with my Airtronics MX3S 27mhz FM tx. I can't seem to locate any - not on ebay or on the major online hobby shops. I'm assuming that, since they "fell out of favor" as bentgear put it, they're few and far between. Does anyone know where I might be able to buy one or more? Thanks.
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RE: 27mhz or 75mhz, why the diffrence?
My company has 27MHz FM sets for Airtronics andFutaba. Sales have been ho-hum for these with the 27Mhz AM still our highest selling SKU. We sell a LOT of the 27Mhz AM 'Funnies' to dealers in the UK who re-sell them to buyers in the US! With about 15 channels, we hit all of the in-between channel numbers of the standard 27MHz AM sets that have a frequency channel spacing of 15KHz.