(N2EY) wrote in
:

In article , Mike Coslo
writes:

N2EY wrote:
In article , Mike Coslo
writes:

But even if that is the case, it would seem to me to make more sense
to us a limit that is easily handled by virtue of equipment that will
handle the limit already on the market.

Exisitng equipment could still be used by LP licensees - they just
have to turn it down by 3 dB.

Yes, of course.

So what's the problem?

Would the manufacturers make equipment that only put out 50
watts?
Possibly, but what will be the resale value of the equipment? So the
new Class A ham has to go out and buy a new rig to make use of his or
her new priveliges? Remember not everyone wants to run a lot of
power. 100 watts is something most people are comfortable with.

When the Novice was created back in 1951, the power limit was 75
watts input. Which works out to about 50 watts output.

In a short time there were many manufacturers making transmitters for
the Novice market. Their resale value was good because there were
always new Novices coming along looking for a bargain.

And those manufacturers had to compete with homebrew and surplus rigs
which were in abundance back then. (One of the reasons Novices were
limited to 75 w xtal control was so that homebrew rigs used by
Novices would be kept simple).

In fact many Novices used less than the full power allowed.

In another post there was discussion about QRPers being mostly
experienced, operators, not beginners.

But back in 1967, when I got my Novice at the age of 13, my first
transmitter (homebrew, of course) ran all of 10 watts input. Output was
maybe 5 to 7 watts, antenna was a wire out to the crab apple tree in
the back yard. Had a lot of fun on 80 CW with that setup, even though I
was not very skilled back then.

Let's see...there was the Ameco AC-1, the Heath AT-1, DX-20, DX-35,
DX-40, DX-60 and HW-16, the Johnson Adventurer, Challenger, Navigator
and Ranger, the
Drake 2-NT, the Hallicrafters HT-40.......to name just a few.

And this was when the amateur radio market was a lot smaller than it
is today.

No argument with any of your points, Jim. But that isn't today.
Today
the standard HF rig puts out 100 watts.

My point is simply that when the new license appeared, the
manufacturers quickly came up with rigs that matched the privileges of
the license.

How much time do you think it would take Ikensu to come up with 40-50
watt versions of their rigs? Heck, they already make 10 watt versions
for their domestic market.

And the rationale for the reduction of power needs to be proven
to me
anyway. How many Technicians have been hurt by using more than 50
watts power?

Under Hans' plan, no existing hams would lose any privileges. So they
don't have to worry.

But that isn't answering my question. Perhaps I should phrase it
better. If technicians, who are allowed to toy with 1500 Watts, are not
being harmed by their hobby, then what is the reason for limiting their
power? More on this in a minute

One reason is to simplify the test. If the power level is kept low
enough, many of the RF exposure questions can be eliminated from the
test.

And do you think that the prospective ham should not know about RF
safety until they reach the equivalent of an Extra? This plan seems
to advocate that.

Until a few years ago there were no questions about RF exposure at
all in the pools.

Are you arguing for or against this, Jim? If there were no
questions on

RF exposure, and hams did okay, but we should limit new hams to 50
watts because of safety concerns - it just isn't a good argument to me.

The hazards of RF exposure, even at relatively low levels, are better
understood now than before. But there is still a lot of work to be
done. Meanwhile, it makes sense to reduce exposure when possible.

One question is being overlooked, though: Why are most manufactured
rigs rated 100 watts? Why not 50 watts, or 250 watts, or something
else? (A very few are rated at other power levels). Why 100.

The answer is about 50 years old.

Sometimes change is good, and sometimes change is not so good.

All progress requires change, but all change is not progress.

All change comes from within the framework of what exists at the time
of the change.

Sometimes the framework is demolished by the change, though.

If we were to propose a class A class B system from scratch, then I
might say this is a good idea.

But it isn't a system from scratch, it's a tack-on to another system.

So we'll end up with:

1. Technicians - 1.5 kW privileges but no HF privileges, license
period 10 years renewable.

2. Generals - HF plus 1.5 kW privileges, but no access to Extra
sections. License period ten years renewable.

3. Extras - all privileges, license period ten years renewable.

4. Class B - all privileges, 50 watt power limit, license period 10
years non renewable.

5. Class A - All privileges, full power, non expiring license.

I see it differently. First off, Extra and Class A will probably be
merged because there's essentially no difference. Maybe when an Extra
renews, he/she would get a nonexpiring Class A

Second, we'd still have Novices and Advanceds as well as the other
classes, until the last of those licenses expires or upgrades.

Now I would like to know why this is a better system than what I
would
propose, a 3 tier system in which the setup is much like today.

Have you seen my three-tier system proposal?

The only
difference would be that if Morse code testing were to go away, the
writtens would be beefed up a bit.

That's going to be a very hard sell. In fact the "21st Century" folks
want the opposite, at least for the entry level license.

I suspect this system would more likely find favor with the FCC. No new
databases, and similar to something already in place.

They're currently maintaining a six-class database system.

All the safety issues are moot. I haven't seen the harm done by
over 50

watts. In fact, is it even that *good* of an idea to look at limiting
power on the basis of "safety"? I mean if 50 Watts is safer than 100,
maybe 25 is safer than 50. Maybe the FCC should look very closely at
the power levels that hams use. Maybe all hams should be limited in
power so we don't hurt ourselves with RF. Could be a real can of worms
to open.

It was done 7 years ago. In detail. That's how we got the curent rules.

I don't agree with all of Hans' proposal, but he *does* present some
fresh new ideas, rather than simply patching up the old 1951 vintage
system one more time.

And his proposal isn't just another "get rid of the code test and
everything will be fine" things, either.

It's really fascinating to read the reactions, too.

--

And now the answer to the "why 100 watts?" question.

The following is Just My Opinion.

Back about 1950 or so, RCA announced a new transmitting tube, the 6146.
It had been designed to eliminate many of the problems encountered with
other tubes of similar power rating, like the 807. Its design was based
in part on comments and suggestions from ARRL Technical Editor George
Grammer (SK)

The 6146 was an instant hit with hams, because its electrical and
mechanical characteristics were just what hams were looking for. A
single tube would produce 50-60 watts on HF at full ratings, and a pair
would do 100-120 watts output. Both homebrewers and manufacturers used
the 6146 and its cousins (6883, 6159, etc.) in a variety of ham rigs.
The most popular setup was a pair of them, producing a nominal 100
watts. Many small rigs used one tube, and at least two (Johnson Viking
Valiant, Yaesu FT-102) used three of them. Of all the ham rigs made
with tube finals, probably the most popular setup was "a pair of
6146s".

(but none of the Southgate rigs use that tube!)

When SSB transceivers became popular, almost all of them followed the
lead set by Collins in the KWM-1 and KWM-2, and used a pair of 6146s to
get 100 W.

One noticeable exception was Drake, who used sweep tubes. Oddly enough,
many Drake owners are converting their rigs to use (you guessed it)
6146s.

So when transistors began to replace tubes in the final stages of ham
rigs, most of the manufacturers designed for the 100 W power level.

On top of all this was the development of grounded-grid zero bias
"Class B" (actually, Class AB2) linear amplifiers for amateur SSB use
in the 1950s and '60s. Most designs required "50 to 100 watts" of drive
power - perfect match for the usual 100W rig. A quad of 811As, pair of
572Bs, a single or pair of 3-400Zs or 3-500Zs, or a single 3-1000Z were
(and still are) common designs. Now ee have ceramic-metal indirectly
heated tubes like the 3CX800A7 which require less drive, but the old
habits die hard...

73 de Jim, N2EY


You might be right about needing a 100W rig to drive most linears, but not
about the 6146s. A pair of 6146 tubes will deliver 280W upto 30 MHz and
half that upto 60MHz acoording to the spec. The old Yaesu FTDX-560 was
rated at 280W out with a pair off 6146s (560W input power, hence the model
number).

73 de Alun, N3KIP

Alun wrote:

(N2EY) wrote in
:

In article , Mike Coslo
writes:

On top of all this was the development of grounded-grid zero bias
"Class B" (actually, Class AB2) linear amplifiers for amateur SSB use
in the 1950s and '60s. Most designs required "50 to 100 watts" of drive
power - perfect match for the usual 100W rig. A quad of 811As, pair of
572Bs, a single or pair of 3-400Zs or 3-500Zs, or a single 3-1000Z were
(and still are) common designs. Now ee have ceramic-metal indirectly
heated tubes like the 3CX800A7 which require less drive, but the old
habits die hard...


You might be right about needing a 100W rig to drive most linears, but not
about the 6146s. A pair of 6146 tubes will deliver 280W upto 30 MHz and
half that upto 60MHz acoording to the spec.

You're mistaken, Alun. A single 6146B is rated at 61 watts output in
AB1. So a pair would be at the 120w level.

The old Yaesu FTDX-560 was
rated at 280W out with a pair off 6146s (560W input power, hence the model
number).

You're half right. The FT-DX560 was rated at 560w PEP input power but
it used television sweep tubes.

Dave K8MN

In article , Alun
writes:

You might be right about needing a 100W rig to drive most linears, but not
about the 6146s.

Check the ratings. You'll find that I'm right. Sorry, Alun, but I checked my
info before posting and it's accurate.

A pair of 6146 tubes will deliver 280W upto 30 MHz and
half that upto 60MHz acoording to the spec.

The 6146 is rugged, but not that rugged.

The maximum rated power output of a pair of 6146s in Class AB2 *audio* service
is 131 watts. Typical Class AB1 RF service will deliver less.

6146Bs can deliver a bit more. But even at maximum ratings, a pair of 6146Bs is
only rated at 240 watts *input* (Class C).

The old Yaesu FTDX-560 was
rated at 280W out with a pair off 6146s (560W input power, hence the model
number).

560 W input is more than three times the maximum rated input power for 6146s
and more than twice the rated input power for 6146Bs.

The FTDX-560/570 (570 was a deluxe model rated 10 W more) and the earlier
FTDX400 did not use 6146s or any member of the 6146 family.

Those old Yaesus all used 6KD6 sweep tubes, as did the FL-2000 amplifier. (The
FL-2000 was based on a QST article of about 1968 in which up to six 6KD6s were
used in a low-cost amplifier).

But don't take my word for it. NJ7P has a neat tube database, and there are web
pages devoted to early Yaesus.


73 de Jim, N2EY