150% Positive Peaks

[Pete, WA2CWA]

Pete, I think Joe makes a reference to 3.705 that it can resemble the gentleman's band, on 160M at times.

Although, the area around 3.705 is far from resembling the "gentleman's band". Got to remember this is 75 meters.

I'm starting to study for the Extra class to get below 3.700 and enjoy some AM there.

Fred

With the active discussion and proposals about cutting 50 KHz of the Extra phone band portion for data modes since there seems to be a notion of lack of activity ( http://amfone.net/Amforum/index.php?topic=37939.0 ), more Extras should operate down there to make some noise on a regular basis.

[steve_qix]

Yup. It's one is 13 months old and #2 is 3 months in the oven.

Jon

Congratulations!  When I finally had 2 kids, I was pretty much off ham radio for quite a while.  Got back into it once they got older.  Now we're empty nesters. Time flies!!!!!

[ka1tdq]

When she was pregnant with the first one, I was in a mad dash to get everything built before he was born.  I figured I wouldn't have much time after that.  I completed the linear before he was born, but then started the single FET rig after his birth.  I managed to get that one done with the mother-in-law living with us and helping out. 

Next project is simple... building a power supply for an Elmac A54 that I got from eBay.  And I'm slowly gathering parts for the 8 FET E rig.  I've started drilling holes on the heat sink for the RF FETs.  Not a big start, but it's a start.

Jon

[W3GMS]

Pete, I think Joe makes a reference to 3.705 that it can resemble the gentleman's band, on 160M at times.

Although, the area around 3.705 is far from resembling the "gentleman's band". Got to remember this is 75 meters.

I'm starting to study for the Extra class to get below 3.700 and enjoy some AM there.

Fred

With the active discussion and proposals about cutting 50 KHz of the Extra phone band portion for data modes since there seems to be a notion of lack of activity ( http://amfone.net/Amforum/index.php?topic=37939.0 ), more Extras should operate down there to make some noise on a regular basis.

My reference is that many of the same op's and style are the same on 1.885 and 3.705.   So much so that I seldom get on 1.885 much anymore.   We all have preferences of where we enjoy operating and I find 3.705 very enjoyable.  This conclusion for me has been derived from over 45 years on 160 and comparing it to whatever time the 80M sub-band has been available to us for phone operation.  Other than some of the AWA AM events along with the AM TX rally, I just don't enjoy operating within the "Getto" on 75.  Some people like the adrenalin rush of the happenings on 3.873 but I just don't enjoy the level of confrontation.  As I said, to each their own and be glad we can pick and choose what floats our boat and operate in the part of town we enjoy.

This difference of opinion between our operating styles and what various people enjoy is just something that we all need to respect and move on.     

Joe GMS       

[W3GMS]

Although, the area around 3.705 is far from resembling the "gentleman's band". Got to remember this is 75 meters.

Your wrong again Pete, this is the 80M band and not the 75 meter band and I suggest you spend more time listening and joining in on the many great AM QSO's on 3.705!   

Joe

[Pete, WA2CWA]

Although, the area around 3.705 is far from resembling the "gentleman's band". Got to remember this is 75 meters.

Your wrong again Pete, this is the 80M band and not the 75 meter band and I suggest you spend more time listening and joining in on the many great AM QSO's on 3.705!   

Joe

75 meters and/or 80 meters; I'm sure the readers get the point. When I do operate 75/80 meters, I actually spend most of my 75/80 meter operating somewhere between 3705 and 3725. But, I'm also one who generally enjoys one on one type QSO's, so very very rarely will I join into a roundtable. Some AM roundtable-type QSO's, unless they're break in-type, are a perfect remedy for insomniacs. You'll also very rarely find me on 75/80 meters during the late afternoon or early evening hours unless maybe on a weekend. I generally hit the 75/80 meter band during the late evening hours after 10 or 11 PM.

[N1BCG]

One egregious example of excessive bandwidth turned out to be a 20kHz subcarrier. The operator was running some kind of brokered programming.

[w1vtp]

One egregious example of excessive bandwidth turned out to be a 20kHz subcarrier. The operator was running some kind of brokered programming.

 

[w1vtp]

I enjoy all of you as company.  We all have different personalities interests..  I cannot remember anyone I have met in the AM community - who is in conversation with me that I did not appreciate.  The only blight I can see on 75 or whatever band are those who jam QSOs or throw their carrier on without IDs  or generally go out of their way to be obnoxious.

It's sort of like going to a party - there are some I would naturally be attracted to and some who after getting to know I sort of just wander off somewhere else.  Pete (CWA) I would like to hear you on more often.  I can't remember the last time I've heard you.

Al

[Pete, WA2CWA]

Pete (CWA) I would like to hear you on more often.  I can't remember the last time I've heard you.

Al

The most recent time I heard you Al was on 40 meters. I think the last time we worked on 75 it was after 12 midnight. I think you said you couldn't sleep or had to pee or something and decided to play some radio since you were up. I'm on almost every day but generally roam the 10 and 15 meter bands with an occasional pop up to 6 meters.

Occasionally, like today, you can find me on 20 meters generally using some vintage SSB transmitter or transceiver.

[N2DTS]

I went the other way today.
I hooked up the four 4-125 rf deck to the push pull parallel 100TH mod deck and ran 500 watts carrier and 1500 watts pep.
That is what the rig wanted to do at 90% negative so that was what it did.
No color on the plates of the 4-125's.
Had a very nice long qso with W8LXJ (Bob) for hours.

[w1vtp]

Pete (CWA) I would like to hear you on more often.  I can't remember the last time I've heard you.

Al

The most recent time I heard you Al was on 40 meters. I think the last time we worked on 75 it was after 12 midnight. I think you said you couldn't sleep or had to pee or something and decided to play some radio since you were up. I'm on almost every day but generally roam the 10 and 15 meter bands with an occasional pop up to 6 meters.

Occasionally, like today, you can find me on 20 meters generally using some vintage SSB transmitter or transceiver.

Couldn't sleep.   Don't have that other problem 

Give me a call some time if you hear me.  I don't think 20 meters would work for us

Al

[ka1tdq]

Off topic, but quick question...

Steve:  The output coil for your 8 FET class E rig for 75 meters has a value of 5uH.  That give is an Xl value of 122 ohms.  Do I just calculate the new coil value for 7.293 MHz using the 122 ohm value?  If so, it comes out to 2.66uH.

The reason why I ask is because I found a nice commercially made coil that I just need to cut for the specific value.

Jon

[steve_qix]

Off topic, but quick question...

Steve:  The output coil for your 8 FET class E rig for 75 meters has a value of 5uH.  That give is an Xl value of 122 ohms.  Do I just calculate the new coil value for 7.293 MHz using the 122 ohm value?  If so, it comes out to 2.66uH.

The reason why I ask is because I found a nice commercially made coil that I just need to cut for the specific value.

Jon

That's pretty much right.  Cut the tank capacitor and the coil if half from whatever values you use on 75 meters and it should work.

Regards,  Steve

[N1BCG]

I went the other way today.
I hooked up the four 4-125 rf deck to the push pull parallel 100TH mod deck and ran 500 watts carrier and 1500 watts pep.
That is what the rig wanted to do at 90% negative so that was what it did.

Interestingly, the ideal carrier/sideband ratio topic came up in a 40M discussion with K1KW on Saturday. There are infinite combinations of carrier level and sideband level that result in a 1500 Watt PEP, but where is it optimal?

For example, you can get 1500PEP with 375W@100%, 200W@174%, and at the extremes, 1500PEP DSB with no carrier and 1500W CW with no mod.

Here's something else to consider. Back in the 80s, Leonard Kahn developed his "Powerside" system for AM b'cast stations. It emphasized one of the sidebands and suppressed the other so that the total carrier + sideband energy remained the same. This was to help stations that experienced interference from other stations on first adjacent frequencies by concentrating the modulated energy in the sideband furthest from the other station. Cool, eh? And the FCC approved it.

We had this system at my 1490 station since we got slammed by then WTOP 1500 in DC. It was effective for analog receivers, but unfortunately, it came at a time when digital tuning became the norm, so there was no practical way to tune slightly to the stronger sideband.

Makes me wonder about an amateur radio application since sideband cancelation due to propagation would be reduced.

[N2DTS]

Well, I often do that on the receive side with the sdr.
sdr-radio has buttons that allow you to select upper or lower sideband only AM reception, which works well if something is on one side causing interference.
You can also slide the passband over and it seems to work about the same way.

There ARE guys running single sideband with a carrier, I used to have a KWS-1 which did that, sounded nasty.

Its not like the carrier does not do anything, it quiets the frequency, and a big strong carrier is nice.
You just need to put enough audio on it to be heard.
Are we working DX? Or are we having pleasant round tables or break in?
There is no need to sound like a commercial on TV with super loud audio, and any distortion (in the rig or in the detector) just makes copy harder.

Get the peaks going the right way, control the negative modulation, use some mild compression to keep the audio level up, do a little EQ if needed and call it good.

 

[K4RT]

One egregious example of excessive bandwidth turned out to be a 20kHz subcarrier. The operator was running some kind of brokered programming.

You experienced this on a broadcast band or amateur radio band?

[w1vtp]

<snip>

There ARE guys running single sideband with a carrier, I used to have a KWS-1 which did that, sounded nasty.

Its not like the carrier does not do anything, it quiets the frequency, and a big strong carrier is nice.....

I think that's a common problem with the KWS-1.  I know of two operators of KSW-1 and they both have that problem.  Problem is with the carrier and the drifting problem the KSW-1s have nowadays it's very challenging listening to them on SSB.  I still don't get why Collins didn't simply add a separate AM board instead of that "Oh, by the way, here's AM" approach.  My FT-301 has a separate  AM board as, I am sure, do other rice boxes.  The KSW-1s need a lot of maintenance to bring them up to the original standards.  Not sure if the drifting problem has a fix.

[ka1tdq]

I was bored, so I made a YouTube video showing 180 watts carrier and my highest voice peak was 1200 watts.

After reviewing the video, I really appreciate the need for class E stuff.  I'm belching out so much blower noise for PW power.

Anyway, here's the link:

https://www.youtube.com/watch?v=wCbCmiNE2rY

...not a lot of activity on 40 meters tonight.

Jon

[N2DTS]

I can do that with tubes and no blowers, just a muffin fan on 1/2 speed.
More like 200 watts carrier and 1000 watts pep without any negative peak clipping.
A pair of 4-400's with screen modulation would do 300 watts, 1500 pep and not need any fans or blowers, 10 Hz to 20KHz if you want.

With the dx60B/qix modulator and the pair of 4x150's I could do 25 to 200 watts carrier and 600 watts pep.

Things tend to sound better with normal 4 times carrier mod levels though.

The amount of electricity I used for radio does not matter to me, my wife uses more to dry her hair...