[Antennas] 80 m vs. 75 m

Thu Apr 24 02:31:22 EDT 2008

Aha! Great clarification! Thanks all!
/Micke
On 23 apr 2008, at 19.42, David Kelley wrote:
> By way of further explanation, you might recall that the formula for 
> wavelength in free space is lambda = c/f, where c is the speed of 
> light in free space (3 x 10^8 m/s) and f is frequency in Hz. If you 
> do the calculation for 3.75 MHz (the top of the old CW sub-band in 
> the US), you get 80 m. For 4 MHz (the top of the SSB sub-band in 
> the US), you get 75 m. The use of the 80 m and 75 m designations is 
> really just a way of differentiating the CW and SSB sub-bands. In 
> the US, 80 m = CW and 75 m = SSB.
>> 73,
> Dave NB4J
>>> At 01:19 PM 4/23/2008, you wrote:
>> Hi Wayne,
>>>> 80m refers (informally) to the lower half of the 3.5 - 4.0 MHz band 
>> (3.5 -
>> 3.75 MHz). 75m refers, also informally, to the upper half (3.75 - 
>> 4.0 MHz).
>> The two designations are often used interchangeably in Region 2; 
>> the band is
>> not officially segmented in this way.
>>>> The Region 1 allocation is 3.5 - 3.8 MHz, so European hams refer to 
>> this
>> band as 80m, but not as 75m.
>>>> Cheers for now, 73,
>> Adam VA7OJ/AB4OJ
>>>>>> -----Original Message-----
>> From: antennas-bounces at mailman.qth.net
>> [mailto:antennas-bounces at mailman.qth.net] On Behalf Of DW Holtman
>> Sent: 23-Apr-08 06:35
>> To: Mark; Antenna Mailing List :>
>> Subject: Re: [Antennas] Eighty Meter mobile or portable
>>>> Hello,
>>>> I hope this simple question doesn't start another war.
>>>> What is the difference between 75 and 80 meters on the ham bands. 
>> Is there a
>> difference? They are frequently interchanged. Are the ham bands 
>> broke up
>> into two segments?
>>>> Best,
>> Wayne
>> ______________________________________________________________
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