I have a 757gx and an FT-101B. I have listened to the guys on 75m and wondered if the wattage my radios put out for AM is sufficient to have a good QSO there? The 757 is 25w on AM and the 101 is 30-40w for AM. Do most people use an amp for AM ?
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Question About Using AM mode on HF
- Thread starter Sonwatcher
- Start date
Probably not reliably, best thing you can do is give it a shot... Most of those guys Are running "Big Iron", Boat Anchors, whatever you want to call them... Vintage Transmitters, some Home Brew, some rebuilt AM broadcast transmitters, and probably most popular are the old Transmitters like Johnsons, Collins, Globe, Heathkit, ETC.. Do definitely give it a shot, maybe you'll catch the bug and be shopping for your own Vintage BA.... 
The 101 will have better sounding AM audio. I do not thisk I have seen a modern day rig that has good AM audio nowadays. Wonder why?
Most of the AM crowd runs the old stuff with big amps. Legal power of coarse.
Most of the AM crowd runs the old stuff with big amps. Legal power of coarse.
Most don't have the filter width to pass the audio, that's the main reason. Have to add the optional AM filters and even most of those are just 8kHz so that's a 4kHz audio pass band...which certainly sounds decent, but not like the ridiculous 20kHz that the transformer modulated setups a lot of the class E guys use, which gives you a 10kHz audio pass band width.
You can certainly talk to people on AM with a 25W carrier rig, if the conditions are decent...that's the key. The band has to be pretty short and not noisy, but it's certainly possible and fairly often doable.
Just be sure you have something to add to the conversation if you jump in or you'll take a beating. The AM crowd tends to be highly technical and they don't spare much time for people with nothing to add to the conversation that is going on either.
I have to say I love to learn but when it comes to adding something to an electronics based conversation I am mostly at a loss. I have absolutely no electronics background, zip, nada . Anything I have gleaned has been recent from listening and reading. Way below a lot of the fellas I hear on the bands. I do enjoy listening though. Maybe sometime I can find a group of good ole' boys just having a round table on AM .
Take another look at that 25 watt thingy. That's carrier in most cases, not total power. Will that be enough to talk to most people? In most cases, yes. Depends a lot on how 'well' those other people are listening, and how. If they have the RF gain cranked back so that they don't have to listen to noise, just hear the real loud stations, you can probably forget it. Has more to do with what 'they' are willing to do, not what 25 watts will do.
- 'Doc
- 'Doc
25 watts carrier power is plenty enough to have fun with on 80 AM. Use a good dipole up at least 45 feet in the center and pick operating times when the yahoos are fewest. Just before and during dinnertime. Mid morning weekends are good too. Stay away from giant roundtables and try calling CQ at least 7 kc away from existing AM.
You will find the east coast folks are not using mostly older transmitters anymore. Many excellent sounding signals are made with riceburners like your Yaesu. IIRC that rig doesn't use the crystal filter on AM transmit. Even if it does there are modifications which make it work better than any old tube ham transmitter ever could. Boatanchors are fun but there's no reason not to use a lot of newer models.
You will find the east coast folks are not using mostly older transmitters anymore. Many excellent sounding signals are made with riceburners like your Yaesu. IIRC that rig doesn't use the crystal filter on AM transmit. Even if it does there are modifications which make it work better than any old tube ham transmitter ever could. Boatanchors are fun but there's no reason not to use a lot of newer models.
That would depend heavily on conditions, 25 watts is not going to be sufficient to hold a "good qso" on a regular basis, to make contacts, yes...
short occasional contacts are a tad different then what I would consider a "good qso" Guess this all depends upon exactly what wants to be accomplished, but I gathered the OP was interested in partaking in those roundtables with those "Yahoos"
LOL, you must know a different bunch then I do....
Very few modern transceivers are capable of delivering an "excellent sounding signal" on AM, the 101 does a nice job though... You are right though the AM filter in the 101 is only active in RX, and then only after mods.
The audio quality/fidelity that a stock 101 is capable of producing, or any other modern amateur transceiver for that matter is not going to be better "any old tube transmitter ever could" on AM....
while a couple of the most recent Icom offerings are passable on AM, All modern HF transcievers are low-level AM modulation and simply sound like shit... I guess if your half deaf most of what you say could be considered fact. Guess it all boils down to what you consider passable quality, however they shouldn't have even bothered including AM transmit on 99%...
If the original OP is seriously interested in getting into AM I would suggest going on over to The AM Forum - Index, lots of good info, and even a Mod or two for a few modern rigs to improve the AM tx.
While the following post may seem somewhat comical, it actually isn't far off...
Quoted from The Five Hurdles - K1JJ
Quoted from The Five Hurdles - K1JJ
The Five Hurdles
Tom K1JJ.
I often hear new AMers asking " What do I need to put together an AM station that is considered "advanced" "?
IE, "How can I cut right to the chase and be a strapper right away"?
Just what goals or systems do I need in place to fully appreciate what fidelity AM has to offer for both transmitting and receiving?
How do I test my gear to insure it's doing just that?
And, how can I give out accurate audio reports to help other newcomers?
Here's one ham's opinion as to where to focus your energy to arrive at these goals. This and the next series of articles address these and other important questions.
1) I feel the first thing any AMer (worth his salt)should do is set up a decent, ~8-12kc wide-band receiver. It's MANDATORY to pick off the audio from the detector and drive an external >20watt hi-fi amplifier with big, good speakers....four speakers mounted on the four ceiling /wall corners. Audio sweep the complete RX system from antenna to 8 ohm audio output to be sure it is clean and really goes 20-10,000 hz. Those I.F.'s can fool you sometimes.
So many times I've visted shacks where guys think they have good rx audio with a "stock" or even modified receiver...but are really missing the deep lows and high end - not to mention the inherent distortion generated by most receiver audio sections.
Until one has heard the likes of WA1QIX, K1KW, W2INR, WA1HLR, KG2IR, AA3WH and others in ass kicking loud "FM Radio Quality" surround sound, it's hard to accept what I'm saying. It's truly amazing how good these guys sound when they rumble the room and you can hear their subtle breathing, (panting) sighs and the clean high frequency harmonics of their voices.
The receiver detector into a hi-fi amplifier /big speaker system is the only way to get this sound.
Turn up your high end FM stereo on a mellow radio announcer sometime to see what I'm talking about -these AMers sound even better.
Listening to fine Hi-Fi RX audio reminds you of why you are in this AM game in the first place - and motivates.
2) The next challenge is to get your AM transmitter to audio sweep cleanly (VERY CLEANLY) from say 40hz- 7kc or higher. On the scope. This in itself is a challenge.
Once this is accomplished, THEN add the EQ's, processors, expensive mics, etc. Without this transparent transmitter audio, all this stuff is just fooling yourself with trying to match a peaky transmitter with a mic/system that will try to compensate...along with distortion generated by boosting areas that are lacking, non linearities, etc. Cat chasing it's tail... endless asking for reports on the air.
3) Lastly, one needs a good recording system that comes off the detector of the wide band receiver and can play back through your flat transmitter in a transparent manner. This is the best, most informative audio report/service you can give anyone. Nothing else has to be said once it is played....guys react immediately to what they must do once it is heard. Most will then adjust their EQ/processing to satisfy themselves, not the infinite amount of opinions of others who have their own agendas as to what kind of audio THEY prefer or what YOU should sound like.
IE, ask Irb how you sound, then ask Nick...two totally different opinions...and everyone else is gonna say differently too!
IE, ask for a tape, not an opinion when adjusting your rig. And remember, you need a hi-fi RX system as described above to really hear what is being played back to you!
4) Dipole at 50' for 75M.
5) At least 250 watts of carrier and a quiet room background. Little or no blower noise.
Tom - K1JJ
LOL ! Thanks guys. Using an amp is not economically feasible right now. Maybe my best bet is to try and listen for 10m am stations in the 29.000-29.200 area.
lol, give it a shot on 75
, though 10 is much more QRP friendly, even a couple watts when the band is open will do nicely, and with some nice openings recently thats a good chance... Is a group on 10 AM that run converted Johnny I, and II, fun little group.. definitely a cheap way to get a foot in the AM door.. And GOD forbid Run the old converted CB gear Just imagine an old Johnny I (Whiteface) running into a couple sweep tubes in a metal box suspiciously called a "Footwarmer" In case you haven't gathered I'm a big fan of AM, have been since the 70s and no matter what those silly sidebanders say ya just can't get Studio quality audio without Iron
I'd love to get into some AM. I looked at some old gear. I see the Swans had some good power on AM. They seemed to be the cheapest. But do they drift like the Siltronix ?
Is a joke somewhere about where the Swan-net meets, and the Swan 3drifty, but to answer your question without some divine intervention yes they do drift