Question, a Flagship Transmitter sponsored on the forum.

[ka3zlr]

Good Morning,


 I've been thinking, with all the information that has been gathered here and on the other sites why isn't there one transmitter localized on the forum here as a flagship, using today's state of the art, using today's available components, readily made easily built.

 The idea would need to be cleared by our Techs, something on the level of 40 watt, multi-band would be nice, enough power to drive an amp, a flagship transmitter for the masses.


 any thoughts...?..Opinions..?




 

[steve_qix]

The idea is a good one, and is in progress 

As far as a "flagship", it it might be more of an "opinion" thing than something real.   Even the power level would be up for debate.      

For instance, I myself would say a "flagship" transmitter would have to be at least 300 watts or it is not of sufficient power to be a flagship.  But, this is my opinion.  I think of transmitters below 200 watts as low power.  When I use my Pulse Width Modulated Valient, I tell people I'm running low power.  Some people call 5 watts low power.  I call that flea power.  This is just an opinion.

Then, I can imagine the technology issues    Should it be solid state?  Tube? Hybred (tube final, solid state modulator like in my Valient?).  Then, whether it should low power modulated/linear amplified or directly modulated.  Some people swear by linears, some swear at them !!

It seems as if here at AM Phone, we do a good job at presenting several different technologies and methods, and people seem to choose what they are attracted to.

The class E stuff is well publicized, and a fair number of people have built these transmitters, but so have people build the "pair of 813s modulated by a pair of 813s" combination, which is also published here.  And then there are the numerous rice box modifications.


But, I will venture an opinion as something for the "masses", which I am actually working on.  It is this:

Most of the new-ish hams I speak with seem to have rice boxes.  They are everywhere.  Then, they try to use them on AM and of course most of the time, it's bad.  SEVERAL of these folks have asked for a low power AM transmitter (up to 50 watts) which they can interpose between the transciever and the linear amplifier.  This enables the receiver to be used, and the linear to be used, but gets rid of the AM within the transciever.

The device uses the RF (unmodulated) from the transciever as the VFO, and automatically switches in and out when the transciever is keyed.  The audio within the transciever is not used at all (for transmit), and is part of the "AM generator".

The modulator is of very high quality, direct coupled (no transformers), and includes negative peak limiting and audio processing.  Plug in a condenser mic and go - full fidelity AM !

Simple, inexpensive, practical, effective solution to get the (majority) of amateurs on AM without getting into the world of modifiying an, often expensive, piece of equipment.



Anyway, there's one band aide.

Not a flagship in this man's opinion, but certainly practical and effective!!

Regards,

Steve

[w3jn]

I think the two most popular HB projects - "flagships" as you say, Jack - are Steve's Class E implementations and K1JJ's Tesla 360.  Both are well within the capability of inexperienced builders and both highly effective.

[WD8BIL]

SEVERAL of these folks have asked for a low power AM transmitter (up to 50 watts) which they can interpose between the transciever and the linear amplifier.  This enables the receiver to be used, and the linear to be used, but gets rid of the AM within the transciever.

Something on the order of an A.M. "Transverter" ..... eh Steve ?

Hmmm... I've built transverters for 6 and 2 meters in the past. The 6 meter one was based on Drakes TR6 which had tube finals and did 100 watts.

Another Hmmmmm...... might need some looking into.

[KF1Z]

SEVERAL of these folks have asked for a low power AM transmitter (up to 50 watts) which they can interpose between the transciever and the linear amplifier.  This enables the receiver to be used, and the linear to be used, but gets rid of the AM within the transciever.

Something on the order of an A.M. "Transverter" ..... eh Steve ?

Hmmm... I've built transverters for 6 and 2 meters in the past. The 6 meter one was based on Drakes TR6 which had tube finals and did 100 watts.

Another Hmmmmm...... might need some looking into.

He's talking about  using the VFO of the rice-box, to drive a calss-e amplifier that's externally modulated by a PWM (I assume)....

But that's for people that HAVE a rice-box, and HAVE a linear....

What a waste it would be to go out and buy a linear to use just for that.

If you don't already have the Rbox and leeneah... then a full-fledged E-rig is in order!

[WD8BIL]

He's talking about  using the VFO of the rice-box, to drive a calss-e amplifier that's externally modulated by a PWM (I assume)....

Read it again.

which they can interpose between the transciever and the linear amplifier

So it's a given "they" already have a transceiver and leenyar !

[KF1Z]

The only assumtion I made, was that the modulator would be a PWM...

No need to read it again..... I know what he meant....

When I said "what a waste it would be to to buy a linear just for that....."

I was only refering to those people that MIGHT think that it would be easier to buy a linear to use with a rig like that, rather than to build a high-powered e-rig.....


I guess I should be carefull of what I try to type, with only one cup of bean in the morning!!

:-)

[ka3zlr]

Ok, Ok, Ok, Ok,.......slow down..maybe good idea, bad choice of words..my fault...i will rephrase...thought was well meaning ..... i had to take the dog to the vets first thing this Am, i just got back....

 On the order of today's state of hamy hambone, how about a 100 watt rig not pep, pure sine wave at 100 watts...mulit band..with the ability to adapt to a higher outpoot...it would be able to start the job and then grow with the builder...that's a thought...

 

 

[Steve - WB3HUZ]

Why not just let people choose what they want to do instead of trying to put some stamp of approval on ONE approach. Choice is good.

[ka3zlr]

I agree Huz, but the thought is to entice building at a some what entry level, Not everybody is up to building the tesla rig...heck i can't put maybe 5 guys in my area here that have the ability to approach building that......no disrespect meant....

But a sponsored ideal, on the forum here, a nice walk me through build up..then add ...um,...not that this is "the all" approach.. but a budding inspired builders transmitter...

[KF1Z]

Why not just let people choose what they want to do instead of trying to put some stamp of approval on ONE approach. Choice is good.

Well, I'm not doing great with words this morning either, but....

I THINK zlr's  idea was, that if there was, on this site, one COMPLETE transmitter project, for those who are new to the realm of building and/or AM.

You know, schematics, a few words of wisdom.... similar to what you might have found in the old handbooks. Something that goes from VFO straight-through to out-put tank circuit.

I know, there is some schematics etc to be found here and ALL OVER the web....
But, very few complete "how-to" s.
And, if you're new to it... you may not know what type of modulator to use with what configuration of amplifier etc.

That's exactly how I ended up building my e-rig.... I was searching for info on how to build an AM transmitter, had very little luck until I found Steve's site.....


So, yes, when you know how to make a choice, choice is good...
When you don't know... choice is just another variable.

[WD8BIL]

A class E transverter is what I waz suggesting. ie "something on the order of.."

But hell.... I'm just a Buddly. Carry on... I'll just sell all my stuff and keep hunting.

[ka3zlr]

Welp, I've been thinking, I remember Huz said in another thread about the future being "software"..that's fine... my thinking today, why not a laptop AM rig...use the computer and some of these all in one chip building blocks for oscillators, controlled by the computer,.. build up a final amp with the ability to do 100% duty cycle ..... just an idea...

[W4EWH]

I THINK zlr's  idea was, that if there was, on this site, one COMPLETE transmitter project, for those who are new to the realm of building and/or AM.

I vote for a complete kit for a complete transmitter, including "Connect part A to terminal strip 1 (NS)" instructions, just like Heath made. Heath did more to get hams on the air than all other manufacturers combined, just because building the kit was an invaluable way to learn about construction, layout, and wiring.

I also vote for legal limit: with class E, it's no more work than low power.

Profits, naturally, would support the forum.

Bill, W1AC

[KA1ZGC]

Welp, I've been thinking, I remember Huz said in another thread about the future being "software"..that's fine... my thinking today, why not a laptop AM rig...use the computer and some of these all in one chip building blocks for oscillators, controlled by the computer,.. build up a final amp with the ability to do 100% duty cycle ..... just an idea...

The future may be in software, but this is the present.

SDR works awesome for transmitters. That's where the concept shines. Whenever someone sets out to design any kind of transceiver these days, they do so by designing a transmitter that can receive. The problem lies in the receiver.

Today's SDR receivers have only the slightest low-Q filtering in the RF stages, and that's it. No IF at all. The problem there is front-end overload. If a strong signal gets in and saturates the analog-to-digital converter, the receiver simply stops working, no matter what frequencies you and the overload signal are on. If the converter is overloaded, there's nothing whatsoever software can do to compensate. It just stops functioning.

This is bad, IMHO.

Yeah, great, you've got as much defined in software as theoretically possible with today's technology, but that alone doesn't make it perform better. We've climbed the mountain because "it was there", now it's time to climb it again, but without casualties this time.

You can't reflash your microprocessor-controlled fridge to make it into a microwave oven. The right hardware is still key, and the current thinking behind SDR has forgotten many lessons learned that led us to superhet design all those years ago.

I think "sponsoring" (whatever that's supposed to mean) is not necessarily going to make any difference. There are so many disparate ways to get on AM, why suggest to a newcomer that this group primarily endorses one approach as "right" above others? Isn't that the same as the ARRL mentality that pisses us off so much?

If you've got a design, post it, Jack. No need to have it reviewed and "type accepted" by this group. The newcomer should do what's within their means, not what fits others' tastes. They should go with a design that works best for them, not us. They don't need to be handed a cookie-cutter design and told "that's what we find acceptible around here", they can get plenty of that in almost every other facet of the hobby.

My $0.02.

--Thom
Kilowatt Amplifier One Zero Grid Current

[K9ACT]

Can we start over?

What on Earth is a Flagship Transmitter?  Is this the one that the chief Moderator sails?

And... why or how can this list sponsor same?

Is someone going to build them and spam the list with ads for it?

It's great to discuss favorite rigs but this whole discussion or at least the subject, makes no sense to me.

js

[Carl WA1KPD]

I would like to see a "progressive transmitter". You build and use it in prices as your comfort level increases.

I have several old books with that type of design but they are pre WWII.
They follow a format something like this

Chapter 1 is a basic transmitter (6AG7 to 6L6) with a simple power supply.
Chapter II could be a simple modulator
Chapter III could be a VFO
Chapter IV a bigger PA designed to mate with the xmtr
Chapter V a bigger modulator using the original modulator as a speech amp
Chapter VI is about how to really strap

[KF1Z]

I still think the origional idea was simply to have a design with schematics and advice posted here somewhere that someone new to AM and/or building would be able to follow, and put together an AM transmitter....

If I'm wrong... well, ok then, I've missed the point as well.......


The problem usually lies with the people out there that KNOW how to build a modulator, and put it together with an amplifier that they KNOW how to build....
But they are either unwilling, (or more likely, just don't have the time) to compile a simple set of instructions on how to go about building one, and share it with those who want to learn.


Now, there probably is a website somewhere, like QIX's, that does just that...

Well, does anyone know where?

Can any of you point to a particular site, or article, or handbook writing that would enable a "newbie" to be able to buiild their own AM transmitter?


ZLR, correct me if I'm wrong, but is it this kind of idea you were getting at?
Just having somewhere on the site, this type of thing?

[WD8BIL]

Take your pick.

http://www.amwindow.org/tech/htm/k1etppw.htm
http://www.amwindow.org/tech/htm/50c5/50c5.htm
http://www.amwindow.org/tech/htm/ne1stx.htm
http://www.amwindow.org/tech/htm/ne1sps.htm
http://www.amwindow.org/tech/htm/eltx.htm
http://www.amwindow.org/tech/htm/series.htm

Anyone with a genreal class or higher SHOULD be able to do SOMETHING with these !!
(ow!!! that hurt to write.)

[WBear2GCR]

A solution looking for a problem??

Two things:

- you can't spoon feed people that do not want to be fed!
- if JXX and FXE (who I know locally) have both built full fledged variants of the 813 x 813 rig, anyone who wants to can. (neither had much hombrew experience before attempting those projects)

My feeling is that as a group, Steve QIX included, we should not under any circumstances make "getting into AM" the equivalent of buying a store bought rig.

Steve, if your new box idea does not require the buyer to wire things, and read the instructions and schematic, imho you'd not be doing anyone a service! Please give this some thought!

Fact is that anyone who really wants "on" for AM can buy a boatanchor and either do a mod, or else have someone do it for them. But at least there is that minimal effort and the potential (small as it may be) present to get that far, and then to go beyond that point.

This boils down to the "no-code"/"canned questions" licenses vs. the "hard way"/homebrew situation all over again.

My feeling is that if there is no effort involved in getting onto AM, then there is no reward and we pollute and dilute the "gene pool."

More is not always better.

Conversely, I think that perhaps we as a group are overlooking the serendiptious benefit/side-effect of AM and that the participants in AM generally speaking have been - that being we/they/us - are extremely DIY, hands-on, and motivated ops!

A "kit" might be a good idea - but if it doesn't involve some personal effort for the buyer, to me it is probably not a good thing. Parts for a tube style rig would be almost impossible to source today... so would just an output pi-network... (for a kit, you need many of the same thing...) very expensive at best!

Oh, I think that being an AM op should be viewed by the community an elite, special thing (not unfriendly though), that other hams should aspire to[/u]!! 

        _-_-bear


PS. fwiw, I have experience writing step-by-step "heathkit" style instruction books...

[KF1Z]

Take your pick.

http://www.amwindow.org/tech/htm/k1etppw.htm
http://www.amwindow.org/tech/htm/50c5/50c5.htm
http://www.amwindow.org/tech/htm/ne1stx.htm
http://www.amwindow.org/tech/htm/ne1sps.htm
http://www.amwindow.org/tech/htm/eltx.htm
http://www.amwindow.org/tech/htm/series.htm

Anyone with a genreal class or higher SHOULD be able to do SOMETHING with these !!
(ow!!! that hurt to write.)

How do you arrive at that conclusion?

[steve_qix]

A solution looking for a problem??

Two things:

My feeling is that as a group, Steve QIX included, we should not under any circumstances make "getting into AM" the equivalent of buying a store bought rig.

Steve, if your new box idea does not require the buyer to wire things, and read the instructions and schematic, imho you'd not be doing anyone a service! Please give this some thought!

Hi Tom,

Have absoultely no fear in this regard    Any such transmitter that I come up with will absolutely require building by the user, and possibly, but not probably, sourcing of parts.  I can arguably say that providing a kit of parts will provide a much higher probability of success, which is probably a good thing for a beginner - a good reason to provide most of the parts.

Such a transmitter will probably employ a high efficiency analog modulator (simpler to debug and more forgiving) and be more or less indestructable with respect to mistuning, etc.



On kits:  I have done considerable design work with respect to modulators and transmitters over the past 35 years or so, and I have published articles, schematics, plans, how-tos, etc..  Creating something like the old Heathkits would involve MUCH more work.  The kits have to be extensively tested, and built by a reasonable sampling of people with varying skill levels.  There would then be re-testing (after changes), and of course must be FCC type approved for amateur use.  With all that, we're getting into money and much time. 

Would such a kit be financially viable?  That's a question.  If it took, say, 2 people 1 year to do the development and field testing, the time alone would cost over $200,000 (I'm including the loaded overhead rate of 2 people - and I'm using a 1989 number!!) - then you have the parts, sheet metal design and manufacturing, insurance, documentation, etc, etc, etc. consumed in testing and product assurance, and I haven't come close to covering everything.  Could enough kits be sold at a high enough profit margin to make the project viable, or for that matter, to break even?  I'm skeptcial, but am open to ideas and suggestions 

Sure, one could turn out a low quality, half-baked product (there are such products on the market today), but this is not a good thing and I for one wouldn't do it.

Anyway, interesting topic 

Regards,

Steve

[WD8BIL]

How do you arrive at that conclusion?

You're joking.... right ?

[KF1Z]

How do you arrive at that conclusion?

You're joking.... right ?

Of course I'm not joking..

What does being a general class or above license holder have to do with taking a schematic (especially those you posted are all tube type), and turning it into a working transmitter?

[ka3zlr]

I still think the origional idea was simply to have a design with schematics and advice posted here somewhere that someone new to AM and/or building would be able to follow, and put together an AM transmitter....

If I'm wrong... well, ok then, I've missed the point as well.......


The problem usually lies with the people out there that KNOW how to build a modulator, and put it together with an amplifier that they KNOW how to build....
But they are either unwilling, (or more likely, just don't have the time) to compile a simple set of instructions on how to go about building one, and share it with those who want to learn.


Now, there probably is a website somewhere, like QIX's, that does just that...

Well, does anyone know where?

Can any of you point to a particular site, or article, or handbook writing that would enable a "newbie" to be able to buiild their own AM transmitter?


ZLR, correct me if I'm wrong, but is it this kind of idea you were getting at?
Just having somewhere on the site, this type of thing?

 Yes Sir,

 That is precisely the idea...i didn't mean to incite any negativity..