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Transmitting AM on a 6m DIAMOND CP62 Antenna???
Is it possible to transmit AM on this antenna? My local club has a 6m AM net and I want to know if this is capable of transmitting on the AM side. I'm not sure and not experienced with AM transmissions..
Greg D Isringhaus
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Antennas don't care about mode. As long as the SWR is good, it will be fine. AM,FM,SSB,CW Are all the same as far as the antenna knows.
Brad
"Life is just like ridin' broncs, its a battle". Chris ledoux
Long live Steamboat
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No, no, no! If it's not an AM antenna, forget it.
Of course the antenna couldn't care less about mode.
However, it's a vertical. If the other stations in your local net also use verticals, it should be perfect. However, if they use horizontal polarization (beams, etc.) it may not work well at all. For local "direct wave" and even tropo propagation there is a huge disadvantage to running cross-polarization.
Why not find out what they're all using?
A government which robs Peter to pay Paul can always depend on the support of Paul.
-- George Bernard Shaw
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Well, according to this:
http://www.rfparts.com/diamond/pdfdo...structions.pdf
The antenna has about a 1MHz wide BW. Tune the antenna for say 53MHz, and you may have issues if you are running on the lower end of 6m. Where is 6m AM these days?
Also, it states that it is 500W SSB, and 200W FM. I forget how AM is spec'd out; is it total forward peak power; or dead carrier power? Regardless, the typical 100W (or 50W) home station would be fine; but certainly not at 500W carrier! [500W carrier would be what, 1500W at peak forward power? Each sideband being no more than one-half of the carrier power, that is, so as to avoid overmodulation.]
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 Originally Posted by K0GDI
Is it possible to transmit AM on this antenna?
I can't believe this question are you serious?
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If you transmit am on that antenna you will rip the time/space continuum assunder! No really antennas don't care about what mode you use them for. They don't care about anything really. Kinda cold and heartless if you ask me. Now for a more rational response yes you can run am on that antenna, the more important question is does the antenna exhibit a low swr on the frequency you wish to operate at? If it does, everything's fine. If it doesn't, see if you can adjust the antenna to reduce the swr at your desired frequency.
now with true viterbi decoder!
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 Originally Posted by KB1CKT
Well, according to this:
http://www.rfparts.com/diamond/pdfdo...structions.pdf
The antenna has about a 1MHz wide BW. Tune the antenna for say 53MHz, and you may have issues if you are running on the lower end of 6m. Where is 6m AM these days?
Also, it states that it is 500W SSB, and 200W FM. I forget how AM is spec'd out; is it total forward peak power; or dead carrier power? Regardless, the typical 100W (or 50W) home station would be fine; but certainly not at 500W carrier! [500W carrier would be what, 1500W at peak forward power? Each sideband being no more than one-half of the carrier power, that is, so as to avoid overmodulation.]
AM on 6 Meters is toward the low end of the band, just above the area normally used by SSB. 50.4 MHz may be about right. Tuning an antenna intended for AM operation to 53 MHz id dead WRONG. That's the FM region, at least here in the U.S. Some antennas may have a wide bandwidth, but that's a stretch.
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 Originally Posted by KB1CKT
Well, according to this:
http://www.rfparts.com/diamond/pdfdo...structions.pdf
The antenna has about a 1MHz wide BW. Tune the antenna for say 53MHz, and you may have issues if you are running on the lower end of 6m. Where is 6m AM these days?
Also, it states that it is 500W SSB, and 200W FM. I forget how AM is spec'd out; is it total forward peak power; or dead carrier power? Regardless, the typical 100W (or 50W) home station would be fine; but certainly not at 500W carrier! [500W carrier would be what, 1500W at peak forward power? Each sideband being no more than one-half of the carrier power, that is, so as to avoid overmodulation.]
500W of AM carrier would equate to 2000W PEP at 100% modulation (4:1 ratio).
There aren't many ham radio amps that'll do that for very long before cratering.
I have seen one homebrew amp that would do it on 160m but it is a former AM broadcast transmitter (5KW) "retuned" for 160m.
It's the size of a telephone booth.
CW is a manually controlled, message asynchronous, simplex chat mode used without FEC.
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Ah, ok, 4:1. I was thinking 3:1; what can I say? I came along long after SSB ruled the air.
Anyhow, the antenna is low(er) power rated; and the bandwidth, *if set for the FM sub-band*, is not going to let one use AM down where it typically is used, unless if coax loss is decent; or if old-school tube gear is in use. Don't use an amp, and make sure the SWR is tolerable (may need to adjust the antenna, see the instructions), and go for it. Well, assuming you go this route, that is
Good luck!
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The AM "calling frequency" on 6-meters has been 50.400 MHz for well over 6 decades.
With 100-percent modulation you are limited to a maximum of 375 watts carrier on AM which produces 1500 watts peak power.
Glen, K9STH
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