RE: [AMRadio] Re: W3PHL

[UVCM INC]

Joe,
did you have a chance to send the schematic for the BC1G

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of crawfish
Sent: Saturday, February 18, 2006 8:04 PM
To: Discussion of AM Radio
Subject: [AMRadio] Re: W3PHL


Looks like that site with W3PHL pictures is down. One of the locals there
had pictures of the tower which looked like scaffolding. That 3-el. Telrex
at 135 feet was an awesome site. Fred is still around. Has lent his call to
a repeater group in Philly. I can forward the pictures taken from the tower
plus that big transmitter/amp if anyone wants it.
  Joe W4AAB
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[AMRadio] 11-pin plug progress

[John Lawson]

 Well - good thing I've got a Big Box of these little guys - they're 
"flying off the shelves" so to speak.


  To date, somewhere around 50 pieces are spoken for, in three countries 
including the US.


  Late Monday, I'll collate the requests and then start Packing. And 
packing  and packing...   ;}


  I'm very glad that these (fairly rare) connectors came to me in enough 
quantity to keep some classic gear 'on the air'.


  Everyone who has written me so far will get a message back when I'm 
ready to ship to you.


  And I'm sure more names will be added to The List as the weekend wears 
on...



   Cheers

John  KB6SCO

Re: [AMRadio] 11-pin plugs available

[kc7hkp]

Hi John, Do you have any left ?. 5 or 10 would be nice.
--
KC7HKP 
George Yazzolino 
14801 NE 20th Circle 
Vancouver, Wa. 98684 
Grid CN-85

-- Original message -- 
From: John Lawson <[EMAIL PROTECTED]> 

> 
> I have acquired a Generous Quantity (+200) male 11-pin "octal" (yes yes, 
> I know...) male plugs. 
> 
> These are 'chassis mount' type plugs and have waffle-shaped retaining 
> rings with them, but no shells. They are keyed between pins 1 and 11. They 
> are NOS and have never been soldered or used. 
> 
> Free for postage from zip 89706 (Carson City, NV), one to "a handful". 
> Let's be reasonable, here folks... ;} 
> 
> Drop me a line OFF-LIST if any interest. 
> 
> Cross-post this to other BA Restoration lists as you see fit. 
> 
> 
> Cheers 
> 
> John KB6SCO 
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From [EMAIL PROTECTED]  Sat Feb 18 23:03:24 2006
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Looks like that site with W3PHL pictures is down. One of the locals =
there had pictures of the tower which looked like scaffolding. That =
3-el. Telrex at 135 feet was an awesome site. Fred is still around. Has =
lent his call to a repeater group in Philly. I can forward the pictures =
taken from the tower plus that big transmitter/amp if anyone wants it.
  Joe W4AAB
From [EMAIL PROTECTED]  Sat Feb 18 23:10:13 2006
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From: "John Coleman ARS WA5BXO" <[EMAIL PROTECTED]>
To: "'Discussion of AM Radio'" 
Subject: RE: [AMRadio] Re: W3PHL
Date: Sat, 18 Feb 2006 22:09:05 -0600
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I would Like the pictures 
John, WA5BXO

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTE

Re: [AMRadio] AM Transmitter Advice??

[Donald Chester]

Bacon, not trying to be contrite, but where in the old rules did the .25 
second time constant appear?  I have a copy of the old rules and don't see 
it.  It says only that "have the means".


It was not stated in the rules, but the FCC declared in a public notice that 
they would use that measurement standard for enforcement purposes.  I recall 
seeing it somewhere in a 1950's era QST or CQ.  I believe it is also stated 
in the ARRL SSB handbook that was published in the late 50's to early 60's. 
It wasn't an issue until SSB came along.  The equipment manufacturers began 
using p.e.p. to rate their linear amplifiers because p.e.p. inflated the 
power ratings by a factor of two.  It looked more impressive in the ads to 
claim that an amplifer was rated at 2 kw (p.e.p. input) than one kw (average 
dc input).  Kinda like the stereo amplifiers that were (are?) rated at some 
absurd power rating called "peak music power" which inflates the actual 
power  by a factor of several times.  I  recall that the FTC went after some 
manufacturers sometime in the 1960's because they were overly inflating the 
power ratings of their stereo amps.


Strictly speaking, the p.e.p. rule hurt SSB almost as much as AM, if the SSB 
amplifier is operated below the saturation (flat-topping) point.  With most 
human voices, the average power is about 10 dB below the peak power, so that 
with 100% modulation, the average modulation is about 30%.  That's why the 
average level using a V-U meter is set tor about 30%.  So a clean SSB signal 
at 1500 watts p.e.p. should be putting out only about 150 honest-to-God 
watts to the antenna.  Under the old rules it was legal to run a SSB 
amplifier at 1 kw average DC input, and let the peaks go where they may, as 
long as the signal was clean.  That allowed maybe 600 watts r.m.s. output, 
if the amplifier had enough peak power capability to reach that power level 
without flat-topping.  Of course, most slopbucket rigs fall far short, and 
flat-top long before they reach that level, and you hear the garbage 10-15 
kHz on both sides of the signal.  With ALC and speech processing, SSB can 
legally increase its average power to maybe 300-400 watts before splattering 
if everything is adjusted properly.


k4kyv

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Re: [AMRadio] AM Transmitter Advice??

[Donald Chester]

But that high-level balanced modulator loophole was the
reason that the FCC went for the PEP measurement
technique in 1990.  Theoretically, one could have used
a modulator from a 500,000 watt broadcast station on a
1KW upside-down tube final, and it would have been
legal.  They couldn't have that!  Darn it...


They could have gone with average (mean) power output, as read with a 0.25 
second time-constant meter, and the power limit would have been relevant to 
the actual signal strength, regardless of mode.  That way we would have a 
level playing field.


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Re: [AMRadio] AM Transmitter Advice??

[Jim Wilhite]

Needless to say Bacon,  when this was the standard, I wasn't in to looking 
up the specs.  My memory was that the specifications were for taut band 
meters but I don't recall the FCC specifying a time constant for the 
manufacturers to meet.  I don't think the ones used on the Knight Kit were 
compatible.


Most meters of good manufacture such as Weston, Triplett and such were of 
the acceptable standard.  Usually the government, who could not be partial 
to a particular brand, would specify the general accepted manufacturing 
brands.


As I recall the meters you pointed out in the ad for the Drake L-4B were of 
that quality but others made meters as acceptable.  As my flaky memory 
serves, only until the advent of the digital meters, did the specifications 
improve.  But one could not read the peak in digital.


This is my complaint about peak reading wattmeters.  Capacitive hold meters 
are not accurate to the standard that can be called accurate.  So now we 
have the LED reading type but I have never seen a specified range of volts 
that cause one LED to operate and the knee where the other illuminates.


Oh well, just musing and following this topic and enjoying myself.

73  Jim
W5JO

- Original Message - 
From: "Bob Bruhns" <[EMAIL PROTECTED]>

To: "Discussion of AM Radio" 
Sent: Saturday, February 18, 2006 7:00 PM
Subject: Re: [AMRadio] AM Transmitter Advice??



My memory is getting old, and it was always a little
flakey, but I really seem to remember that there was,
at least at one time, an FCC spec on the time constant
of the plate meters in amateur transmitters.

Re: [AMRadio] AM Transmitter Advice??

[Bob Bruhns]

Yep, I think it was a 6-month suspension, not a year as
I stated earlier.  (I plead slightly flakey memory.)

   Bacon, WA3WDR

- Original Message - 
From: "Donald Chester" <[EMAIL PROTECTED]>
To: 
Sent: Saturday, February 18, 2006 8:45 PM
Subject: RE: [AMRadio] AM Transmitter Advice??


> John, WA5BXO wrote:
>
> >As I understand it the trick, that the FCC was to
prevent, and someone was
> >trying to get away with, was to run a 304TL with
about 100 Volts on the
> >plate in a GG configuration.  Forward bias it to a
high plate current like
> >1
> >Amp, so that it acts like a switch that is on.  Then
drive it with 5 KW
> >PEP.
> >It may have been some other some scenario as this
but I think you get the
> >picture.
>
> I had never heard of that, but it makes sense that
someone might try it.
>
>
> > Then there was the trick that a gentleman up in
3 land, I think, was
> >going to run the high level double sideband reduced
carrier generator type
> >rig but he was not reducing the carrier just
increasing the SBs via an
> >extra
> >upside down tube, as it was commonly called.  The
sideband power would
> >continue to go up without distortion (if copied on a
proper synchronized
> >product detector) after the first tube was over
modulated in the negative
> >direction. The voltage and power would be diverted
to the upside down tube
> >where sideband power would continue.  There was
trouble with the specific
> >rule interpretation at the time in the FCC. Of
course any of us today,
> >would
> >be able to see that the upside down tube's audio
plate current and audio
> >voltage must also be counted as part of the input
power.  But the FCC was
> >having trouble deciding, at least as I understand
it.  At any rate, I think
> >they got him for being outside the 40 meter band
limits.  You may remember
> >more of the specifics on this Don.
>
> I knew the gentleman personally.  It was Fred, W3PHL,
near Phila, PA.  I met
> him at many hamfests, and visited him one weekend
back in about 1971.  I saw
> his rig, but by that time he had converted it to a
big SSB linear.  He liked
> to ragchew with VK's and ZL's in the pre-dawn hours
on 40m, using a 120 ft.
> high beam.  He not only fought the FCC, but had to
deal with a tower case as
> well (which he won).
>
> The loophole in the regulations was that the
definition of power was DC
> input to the final.  With the upside down tube
circuit, he ran about 600
> watts DC input, and then applied several kw of audio.
The rig was basically
> a high-level balanced modulator, but with DC applied
to one tube, which
> effectively unbalanced the modulation, he claimed it
was a plate-modulated
> AM rig, and that the legal power measurement was
limited to the DC input to
> the final.
>
> The signal was double-sideband reduced carrier, with
several kilowatts in
> the sidebands and less than 500 watts carrier power.
Althhough a
> synchronous dectector would have have taken full
advantage of both
> sidebands, most of the people he worked actually used
SSB receivers, and
> simply copied either USB or LSB, and used the carrier
only as a pilot
> carrier for setting the frequency on their receiver.
>
> The FCC couldn't make up its mind on how to  deal
with the issue, even
> though they could have cited a rule on the books that
limited modulation to
> 100%, and they could have said he was modulating over
100% in the positive
> direction, regardless of the fact that the signal was
clean.  Instead, they
> ended up citing him for splattering outside the 40m
band.  He liked to
> operate at 7290, and even though he had engineering
data to prove that his
> signal met all FCC specifications regarding spurious
sideband products, they
> said that the rules allow no detectable signal
whatever outside the limits
> of the amateur band, and he had detectable sideband
products above 7300,
> even though they might have been 50-60 dB down.
>
> I understand this whole thing was part of an ongoing
feud between Fred and a
> SSB group that was  competing for the frequency, and
the issue was brought
> up when the SSB group complained to the FCC.  They
suspended Fred's  licence
> for six months based on the citation for out-of-band
distortion products.
>
> The FCC referenced that case when they railroaded
through their p.e.p. power
> rule.
>
> Don K4KYV
>
>
___

>
> This message was typed using the DVORAK keyboard
layout.  Try it - you'll
> like it.
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>
>
>
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Courson/wa3vjb
>

RE: [AMRadio] AM Transmitter Advice??

[Donald Chester]

John, WA5BXO wrote:


As I understand it the trick, that the FCC was to prevent, and someone was
trying to get away with, was to run a 304TL with about 100 Volts on the
plate in a GG configuration.  Forward bias it to a high plate current like 
1
Amp, so that it acts like a switch that is on.  Then drive it with 5 KW 
PEP.

It may have been some other some scenario as this but I think you get the
picture.


I had never heard of that, but it makes sense that someone might try it.



Then there was the trick that a gentleman up in 3 land, I think, was
going to run the high level double sideband reduced carrier generator type
rig but he was not reducing the carrier just increasing the SBs via an 
extra

upside down tube, as it was commonly called.  The sideband power would
continue to go up without distortion (if copied on a proper synchronized
product detector) after the first tube was over modulated in the negative
direction. The voltage and power would be diverted to the upside down tube
where sideband power would continue.  There was trouble with the specific
rule interpretation at the time in the FCC. Of course any of us today, 
would

be able to see that the upside down tube's audio plate current and audio
voltage must also be counted as part of the input power.  But the FCC was
having trouble deciding, at least as I understand it.  At any rate, I think
they got him for being outside the 40 meter band limits.  You may remember
more of the specifics on this Don.


I knew the gentleman personally.  It was Fred, W3PHL, near Phila, PA.  I met 
him at many hamfests, and visited him one weekend back in about 1971.  I saw 
his rig, but by that time he had converted it to a big SSB linear.  He liked 
to ragchew with VK's and ZL's in the pre-dawn hours on 40m, using a 120 ft. 
high beam.  He not only fought the FCC, but had to deal with a tower case as 
well (which he won).


The loophole in the regulations was that the definition of power was DC 
input to the final.  With the upside down tube circuit, he ran about 600 
watts DC input, and then applied several kw of audio.  The rig was basically 
a high-level balanced modulator, but with DC applied to one tube, which 
effectively unbalanced the modulation, he claimed it was a plate-modulated 
AM rig, and that the legal power measurement was limited to the DC input to 
the final.


The signal was double-sideband reduced carrier, with several kilowatts in 
the sidebands and less than 500 watts carrier power.  Althhough a 
synchronous dectector would have have taken full advantage of both 
sidebands, most of the people he worked actually used SSB receivers, and 
simply copied either USB or LSB, and used the carrier only as a pilot 
carrier for setting the frequency on their receiver.


The FCC couldn't make up its mind on how to  deal with the issue, even 
though they could have cited a rule on the books that limited modulation to 
100%, and they could have said he was modulating over 100% in the positive 
direction, regardless of the fact that the signal was clean.  Instead, they 
ended up citing him for splattering outside the 40m band.  He liked to 
operate at 7290, and even though he had engineering data to prove that his 
signal met all FCC specifications regarding spurious sideband products, they 
said that the rules allow no detectable signal whatever outside the limits 
of the amateur band, and he had detectable sideband products above 7300, 
even though they might have been 50-60 dB down.


I understand this whole thing was part of an ongoing feud between Fred and a 
SSB group that was  competing for the frequency, and the issue was brought 
up when the SSB group complained to the FCC.  They suspended Fred's  licence 
for six months based on the citation for out-of-band distortion products.


The FCC referenced that case when they railroaded through their p.e.p. power 
rule.


Don K4KYV

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Re: [AMRadio] AM Transmitter Advice??

[Bob Bruhns]

My memory is getting old, and it was always a little
flakey, but I really seem to remember that there was,
at least at one time, an FCC spec on the time constant
of the plate meters in amateur transmitters.

I did a search, but all I could find was this hint:

http://www.dproducts.be/Drake_Museum/l-4b.htm
Drake L-4B Linear Amplifier
"Plate Current Meter time constant is consistent wit

  Bacon, WA3WDR

- Original Message - 
From: "Jim Wilhite" <[EMAIL PROTECTED]>
To: "Discussion of AM Radio" 
Sent: Saturday, February 18, 2006 7:28 PM
Subject: Re: [AMRadio] AM Transmitter Advice??


> Bacon, not trying to be contrite, but where in the
old rules did the .25
> second time constant appear?  I have a copy of the
old rules and don't see
> it.  It says only that "have the means".
>
> 73  Jim
> W5JO
>
>
>   At that time, plate power input to an AM
> > transmitter was measured by the reaings of DC
meters
> > with approximately 0.25 second time constant.  That
> > time constant would make the meters read average
> > voltage and current, which smoothed out SSB and
> > controlled carrier signals.  But on plate-modulated
AM
> > it did not read true power during modulation,
because
> > it was looking at average voltage and average
current
> > separately, while in AM the voltage and current are
not
> > separate, but they increase and decrease together,
> > resulting in higher power input during modulation.
>
>
>
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Courson/wa3vjb
>

[AMRadio] Re: [FLBOATANCHORS] Replacing sweep tubes with 6146s

[Brian Carling]

On 18 Feb 2006 at 13:25, Mark Foltarz wrote:

> I picked up a Yaesu 570 ( predacessor to FT-101) at the Brooksville hamfest
> today. No finals.
> 
> I seem to remember a few years back an article on converting the finals in a
> FT-101* to 6146s.
> 
> Seems like a good idea now since a 6KD6 sweep tube cost a lot more than a 
> 6146.
> 
> Back when the tube rice boxes came out the sweep tubes could be had for a
> couple of bucks.
> 
> Anyone have thoughts on this potential conversion?

BAD IDEA!

Your mileage may vary. Stay with the 6KD6es and pay the $35 or 
so
for them. You will never regret it.  Hacking into that nice old 
Yaesu could become a dream come true. 
a VERY BAD DREAM!

YMMV = Your mileage May Vary

Re: [AMRadio] AM Transmitter Advice??

[Bob Bruhns]

Hi Jim... Hmm, it came from my sometimes flakey
memory...  I'm pretty sure there was a 0.25 second spec
for the metering somewhere... maybe it was simply
assumed that the meter time constant would be about
0.25 seconds.  I suppose that if someone came up with a
very slow meter, they could get away with huge SSB PEP,
so it makes sense that the time constant of meter
should be specified at least approximately.

In any event, the FCC proceeded as though the DC volts
multiplied by the DC amps gave the average power
input - which was not true for AM.  This Dc metering
ignored the real power increase during modulation,
permitting the upside down tube loophole.  Now if guys
like me had just kept their mouths shut about it, maybe
the FCC wouldn't ever have caught on.  But no, we had
to throw it in the sidebanders' faces.  I plead extreme
youth at the time.

   Bacon, WA3WDR


- Original Message - 
From: "Jim Wilhite" <[EMAIL PROTECTED]>
To: "Discussion of AM Radio" 
Sent: Saturday, February 18, 2006 7:28 PM
Subject: Re: [AMRadio] AM Transmitter Advice??


> Bacon, not trying to be contrite, but where in the
old rules did the .25
> second time constant appear?  I have a copy of the
old rules and don't see
> it.  It says only that "have the means".
>
> 73  Jim
> W5JO
>
>
>   At that time, plate power input to an AM
> > transmitter was measured by the reaings of DC
meters
> > with approximately 0.25 second time constant.  That
> > time constant would make the meters read average
> > voltage and current, which smoothed out SSB and
> > controlled carrier signals.  But on plate-modulated
AM
> > it did not read true power during modulation,
because
> > it was looking at average voltage and average
current
> > separately, while in AM the voltage and current are
not
> > separate, but they increase and decrease together,
> > resulting in higher power input during modulation.
>
>
>
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Courson/wa3vjb
>

Re: [AMRadio] AM Transmitter Advice??

[Jim Wilhite]

Bacon, not trying to be contrite, but where in the old rules did the .25 
second time constant appear?  I have a copy of the old rules and don't see 
it.  It says only that "have the means".


73  Jim
W5JO


 At that time, plate power input to an AM

transmitter was measured by the reaings of DC meters
with approximately 0.25 second time constant.  That
time constant would make the meters read average
voltage and current, which smoothed out SSB and
controlled carrier signals.  But on plate-modulated AM
it did not read true power during modulation, because
it was looking at average voltage and average current
separately, while in AM the voltage and current are not
separate, but they increase and decrease together,
resulting in higher power input during modulation.

Re: [AMRadio] AM Transmitter Advice??

[Bob Bruhns]

That was Fred, W3PHL.  He built a high level balanced
modulator (called the upside down tube circuit), and
biased it to 600 watts carrier input.  Then he applied
a 2400 watt modulator to it.  He used heavy clipping,
like about 30 dB of clipping, and a low-level low-pass
filter.  At that time, plate power input to an AM
transmitter was measured by the reaings of DC meters
with approximately 0.25 second time constant.  That
time constant would make the meters read average
voltage and current, which smoothed out SSB and
controlled carrier signals.  But on plate-modulated AM
it did not read true power during modulation, because
it was looking at average voltage and average current
separately, while in AM the voltage and current are not
separate, but they increase and decrease together,
resulting in higher power input during modulation.

Fred's X volts and Y milliamps held steady with or
without modulation, looking like 600 watts input, even
though easily 3 kilowatts of power were going to that
final amp during modulation.  The way plate input power
was measured at that time, this was legal...  so the
FCC tried to nail him for overmodulation.

Fred countered that overmodulation was a function of
nonlinear distortion, and since his modulator correctly
handled modulation beyond 100% negative, and it was not
saturating at any point, it could not be said to be
overmodulating.  And if the FCC was going to consider
this to be overmodulation, then what about all of
theose guys on SSB and DSB... they would have to nail
all of them for overmodulation, too!

So the FCC resorted to nailing Fred on splatter out of
band.  It was a cheap trick, because Fred's signal was
pretty clean.  But they railroaded it through, and Fred
lost his license for a year.  When he came back on, he
was using some fantastic Marconi high-level multi-pole
filter, and there was no way they could accuse him of
splattering out of the band.  The FCC had lost interest
by that time anyway, and they left Fred alone after
that.

But that high-level balanced modulator loophole was the
reason that the FCC went for the PEP measurement
technique in 1990.  Theoretically, one could have used
a modulator from a 500,000 watt broadcast station on a
1KW upside-down tube final, and it would have been
legal.  They couldn't have that!  Darn it...

  Bacon, WA3WDR


- Original Message - 
From: "John E. Coleman (ARS WA5BXO)"
<[EMAIL PROTECTED]>
To: "'Discussion of AM Radio'"

Sent: Saturday, February 18, 2006 6:39 PM
Subject: RE: [AMRadio] AM Transmitter Advice??


Don,
I have heard rumors of a citation or two but only in
extreme cases such as
10 or 20 KW PEP and I don't know if the rumors are
true.

As I understand it the trick, that the FCC was to
prevent, and someone was
trying to get away with, was to run a 304TL with about
100 Volts on the
plate in a GG configuration.  Forward bias it to a high
plate current like 1
Amp, so that it acts like a switch that is on.  Then
drive it with 5 KW PEP.
It may have been some other some scenario as this but I
think you get the
picture.

An Now, For Something Completely Different.

Then there was the trick that a gentleman up in 3 land,
I think, was
going to run the high level double sideband reduced
carrier generator type
rig but he was not reducing the carrier just increasing
the SBs via an extra
upside down tube, as it was commonly called.  The
sideband power would
continue to go up without distortion (if copied on a
proper synchronized
product detector) after the first tube was over
modulated in the negative
direction. The voltage and power would be diverted to
the upside down tube
where sideband power would continue.  There was trouble
with the specific
rule interpretation at the time in the FCC. Of course
any of us today, would
be able to see that the upside down tube's audio plate
current and audio
voltage must also be counted as part of the input
power.  But the FCC was
having trouble deciding, at least as I understand it.
At any rate, I think
they got him for being outside the 40 meter band
limits.  You may remember
more of the specifics on this Don.

John, WA5BXO

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of
Donald Chester
Sent: Saturday, February 18, 2006 4:41 PM
To: amradio@mailman.qth.net
Subject: RE: [AMRadio] AM Transmitter Advice??


>My understanding was.
>Under the old rules stage or stages, that provide
output to the antenna,
>total power should not exceed 1000 watts DC input.
This includes the sum
>of
>the driver and final in the case of GG output circuit.
>I think that rule was tested.

I recall that was the rule.  But it seems to me it was
much ado about
nothing.  At most, the feedthrough power would be 10%
of the total output
power.  How much signal strength gain could you get
from increasing your
power 10%?

Of course, back in those days the FCC was very nitpicky
about the ham rules,

as they still are with broadcast stations.  But they
have shifted to t

RE: [AMRadio] Replacing sweep tubes with 6146s

[UVCM INC]

I would be interested in seeing theses articles, 25 years ago we had
problems doing the conversation
thanks
Brad

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of [EMAIL PROTECTED]
Sent: Saturday, February 18, 2006 4:04 PM
To: amradio@mailman.qth.net
Cc: [EMAIL PROTECTED]
Subject: Re: [AMRadio] Replacing sweep tubes with 6146s



The conversion to 6146s seems to be a winner in most rigs.  Later today I'll
send you an article on conversions on a Tempo One (Yaesu FT-200) and
FT-101s.

Steve WD8DAS

[EMAIL PROTECTED]

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Re: [AMRadio] Replacing sweep tubes with 6146s

[SBJohnston]

The conversion to 6146s seems to be a winner in most rigs.  Later today I'll 
send you an article on conversions on a Tempo One (Yaesu FT-200) and FT-101s.

Steve WD8DAS

[EMAIL PROTECTED]

RE: [AMRadio] AM Transmitter Advice??

[John E. Coleman (ARS WA5BXO)]

Don,
I have heard rumors of a citation or two but only in extreme cases such as
10 or 20 KW PEP and I don't know if the rumors are true.

As I understand it the trick, that the FCC was to prevent, and someone was
trying to get away with, was to run a 304TL with about 100 Volts on the
plate in a GG configuration.  Forward bias it to a high plate current like 1
Amp, so that it acts like a switch that is on.  Then drive it with 5 KW PEP.
It may have been some other some scenario as this but I think you get the
picture.  

An Now, For Something Completely Different. 

Then there was the trick that a gentleman up in 3 land, I think, was
going to run the high level double sideband reduced carrier generator type
rig but he was not reducing the carrier just increasing the SBs via an extra
upside down tube, as it was commonly called.  The sideband power would
continue to go up without distortion (if copied on a proper synchronized
product detector) after the first tube was over modulated in the negative
direction. The voltage and power would be diverted to the upside down tube
where sideband power would continue.  There was trouble with the specific
rule interpretation at the time in the FCC. Of course any of us today, would
be able to see that the upside down tube's audio plate current and audio
voltage must also be counted as part of the input power.  But the FCC was
having trouble deciding, at least as I understand it.  At any rate, I think
they got him for being outside the 40 meter band limits.  You may remember
more of the specifics on this Don.

John, WA5BXO

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Donald Chester
Sent: Saturday, February 18, 2006 4:41 PM
To: amradio@mailman.qth.net
Subject: RE: [AMRadio] AM Transmitter Advice??


>My understanding was.
>Under the old rules stage or stages, that provide output to the antenna,
>total power should not exceed 1000 watts DC input.  This includes the sum 
>of
>the driver and final in the case of GG output circuit.
>I think that rule was tested.

I recall that was the rule.  But it seems to me it was much ado about 
nothing.  At most, the feedthrough power would be 10% of the total output 
power.  How much signal strength gain could you get from increasing your 
power 10%?

Of course, back in those days the FCC was very nitpicky about the ham rules,

as they still are with broadcast stations.  But they have shifted to the 
opposite approach with ham radio.  Riley's efforts have rooted out the 
rottenest of the apples, but I suspect ham radio enforcement is still pretty

low on the FCC's priority list, as long as the violations don't cause 
interference to other radio services.

Since they changed the power rule, I have never heard of a SINGLE case of a 
ham receiving a citation for running too much p.e.p.

Don K4KYV

___

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RE: [AMRadio] AM Transmitter Advice??

[Donald Chester]

My understanding was.
Under the old rules stage or stages, that provide output to the antenna,
total power should not exceed 1000 watts DC input.  This includes the sum 
of

the driver and final in the case of GG output circuit.
I think that rule was tested.


I recall that was the rule.  But it seems to me it was much ado about 
nothing.  At most, the feedthrough power would be 10% of the total output 
power.  How much signal strength gain could you get from increasing your 
power 10%?


Of course, back in those days the FCC was very nitpicky about the ham rules, 
as they still are with broadcast stations.  But they have shifted to the 
opposite approach with ham radio.  Riley's efforts have rooted out the 
rottenest of the apples, but I suspect ham radio enforcement is still pretty 
low on the FCC's priority list, as long as the violations don't cause 
interference to other radio services.


Since they changed the power rule, I have never heard of a SINGLE case of a 
ham receiving a citation for running too much p.e.p.


Don K4KYV

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Re: [AMRadio] AM Transmitter Advice??

[W5OMR/Geoff]

Donald Chester wrote:




From: "Brian Carling" <[EMAIL PROTECTED]>




Hey - mount those 6AG7s upside down in cooling oil and you
can run 500 watts to 'em.  I wouldn't try it but I am sure
SOMEONE has, LOL!



My very first plate-modulated AM rig back in 1959 used a single 6AQ5 
to drive a pair of 807's as class-B triodes with screen and control 
grids tied together with 20k resistors, and negative feedback round 
the 6AQ5.  It would work for a few minutes, and then distortion would 
start to creep up.  I finally figured out that the 6AQ5 was 
overheating and the distortion was due to thermal runaway.  I turned 
the driver stage, which was haywired on a separate little chassis, 
upside down and let the 6AQ5 rest in a jar of water.  That kept it 
just cool enough to keep away the distortion.  But I would, on the 
average, overturn the jar of water at least once every time I tried to 
use that lashup.


Don K4KYV



John/BXO can confirm this story;

Gene White/WA5ATH(sk) had a plate modulated rig out in his garage, and a 
modulation transformer that made the awfulest racket of talk-back, when 
modulating the rig.  The rig worked well, except for that talk-back.  
Someone (probably Otis/SWK) said "maybe opearte with the transformer in 
a container of oil".  So, Gene did.  But (heh) he kept the oil in a 
styrofoam ice-chest..


The running, on-air, joke was "...what's the oil-pressure on your 
modulator, Gene?"


Mind you, this was also in the days when 'parts was parts' and who 
-cared- what something looked like, as long as it worked!  Therefore, 
several parts were scrapped from rigs that server a different purpose in 
their life, and afterwards, such things as meters that indicated 
"manifold pressure" were used as current meters, etc...  You know how 
home-brewers are.


Ah, radio was a lot more fun, back then :-)

--
73 = Best Regards,
-Geoff/W5OMR

Re: [AMRadio] Replacing sweep tubes with 6146s

[W5OMR/Geoff]

UVCM INC wrote:


mark,
unless someone has a PROVEN swap out it is not a good idea.
Brad KB7FQR



Conversion.  Not a simple swapping out of the tubes.  There's got to be 
some component changes, and some re-wiring, etc...

but, it has, and can be done.


--
73 = Best Regards,
-Geoff/W5OMR

Re: [AMRadio] 11-pin plugs available

[Rev. Don Sanders]

I can use 4 for my current rigs.

Healthfully yours,
  DON W4BWS
- Original Message - 
From: "John Lawson" <[EMAIL PROTECTED]>
To: 
Cc: <[EMAIL PROTECTED]>
Sent: Saturday, February 18, 2006 4:13 PM
Subject: [AMRadio] 11-pin plugs available


>
>   I have acquired a Generous Quantity (+200) male 11-pin "octal" (yes yes,
> I know...) male plugs.
>
>These are 'chassis mount' type plugs and have waffle-shaped retaining
> rings with them, but no shells. They are keyed between pins 1 and 11. They
> are NOS and have never been soldered or used.
>
>Free for postage from zip 89706 (Carson City, NV), one to "a handful".
>   Let's be reasonable, here folks...   ;}
>
>Drop me a line OFF-LIST if any interest.
>
>Cross-post this to other BA Restoration lists as you see fit.
>
>
>   Cheers
>
> John  KB6SCO
> __
> AMRadio mailing list
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> AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
>

RE: [AMRadio] 11-pin plugs available

[DAVID O'NEILL]

Find some females and some 9 pins

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of John Lawson
Sent: Saturday, February 18, 2006 5:14 PM
To: amradio@mailman.qth.net
Cc: [EMAIL PROTECTED]
Subject: [AMRadio] 11-pin plugs available


  I have acquired a Generous Quantity (+200) male 11-pin "octal" (yes
yes, 
I know...) male plugs.

   These are 'chassis mount' type plugs and have waffle-shaped retaining

rings with them, but no shells. They are keyed between pins 1 and 11.
They 
are NOS and have never been soldered or used.

   Free for postage from zip 89706 (Carson City, NV), one to "a
handful".
  Let's be reasonable, here folks...   ;}

   Drop me a line OFF-LIST if any interest.

   Cross-post this to other BA Restoration lists as you see fit.


  Cheers

John  KB6SCO
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RE: [AMRadio] 11-pin plugs available

[DAVID O'NEILL]

I can use 20 for for all the rigs to go to a heathkit p/s 

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of John Lawson
Sent: Saturday, February 18, 2006 5:14 PM
To: amradio@mailman.qth.net
Cc: [EMAIL PROTECTED]
Subject: [AMRadio] 11-pin plugs available


  I have acquired a Generous Quantity (+200) male 11-pin "octal" (yes
yes, 
I know...) male plugs.

   These are 'chassis mount' type plugs and have waffle-shaped retaining

rings with them, but no shells. They are keyed between pins 1 and 11.
They 
are NOS and have never been soldered or used.

   Free for postage from zip 89706 (Carson City, NV), one to "a
handful".
  Let's be reasonable, here folks...   ;}

   Drop me a line OFF-LIST if any interest.

   Cross-post this to other BA Restoration lists as you see fit.


  Cheers

John  KB6SCO
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Re: [AMRadio] 11-pin plugs available

[Joe Walden]

From:
 Joe,w5jdy dba,
Campus Music,
317 White Street,
Norman,Okla. 73069

   I would like to have four of the 11 pin plugs and will send you some cash
for postage...
Email me your address and the total...
Thanks and what a generous offer...  Joe





- Original Message - 
From: "John Lawson" <[EMAIL PROTECTED]>
To: 
Cc: <[EMAIL PROTECTED]>
Sent: Saturday, February 18, 2006 4:13 PM
Subject: [AMRadio] 11-pin plugs available


>
>   I have acquired a Generous Quantity (+200) male 11-pin "octal" (yes yes,
> I know...) male plugs.
>
>These are 'chassis mount' type plugs and have waffle-shaped retaining
> rings with them, but no shells. They are keyed between pins 1 and 11. They
> are NOS and have never been soldered or used.
>
>Free for postage from zip 89706 (Carson City, NV), one to "a handful".
>   Let's be reasonable, here folks...   ;}
>
>Drop me a line OFF-LIST if any interest.
>
>Cross-post this to other BA Restoration lists as you see fit.
>
>
>   Cheers
>
> John  KB6SCO
> __
> AMRadio mailing list
> Home: http://mailman.qth.net/mailman/listinfo/amradio
> Help: http://mailman.qth.net/mmfaq.html
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> AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
>
>
> -- 
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.1.375 / Virus Database: 267.15.11/264 - Release Date: 2/17/06
>
>

[AMRadio] 11-pin plugs available

[John Lawson]

 I have acquired a Generous Quantity (+200) male 11-pin "octal" (yes yes, 
I know...) male plugs.


  These are 'chassis mount' type plugs and have waffle-shaped retaining 
rings with them, but no shells. They are keyed between pins 1 and 11. They 
are NOS and have never been soldered or used.


  Free for postage from zip 89706 (Carson City, NV), one to "a handful".
 Let's be reasonable, here folks...   ;}

  Drop me a line OFF-LIST if any interest.

  Cross-post this to other BA Restoration lists as you see fit.


 Cheers

John  KB6SCO

Re: [AMRadio] AM Transmitter Advice??

[Donald Chester]

From: "Brian Carling" <[EMAIL PROTECTED]>



Hey - mount those 6AG7s upside down in cooling oil and you
can run 500 watts to 'em.  I wouldn't try it but I am sure
SOMEONE has, LOL!


My very first plate-modulated AM rig back in 1959 used a single 6AQ5 to 
drive a pair of 807's as class-B triodes with screen and control grids tied 
together with 20k resistors, and negative feedback round the 6AQ5.  It would 
work for a few minutes, and then distortion would start to creep up.  I 
finally figured out that the 6AQ5 was overheating and the distortion was due 
to thermal runaway.  I turned the driver stage, which was haywired on a 
separate little chassis, upside down and let the 6AQ5 rest in a jar of 
water.  That kept it just cool enough to keep away the distortion.  But I 
would, on the average, overturn the jar of water at least once every time I 
tried to use that lashup.


Don K4KYV


___

This message was typed using the DVORAK keyboard layout.  Try it - you'll 
like it.

http://www.mwbrooks.com/dvorak/
http://gigliwood.com/abcd/

Re: [AMRadio] Replacing sweep tubes with 6146s

[W7QHO]

In a message dated 2/18/06 1:26:00 PM, [EMAIL PROTECTED] writes:


> I seem to remember a few years back an article on converting the finals in 
> a
> FT-101* to 6146s.
> 
> Seems like a good idea now since a 6KD6 sweep tube cost a lot more than a 
> 6146.
> 
> 
Lots of 6KD6s on the e-place.

Dennis D. W7QHO
Glendale, CA

RE: [AMRadio] Replacing sweep tubes with 6146s

[DAVID O'NEILL]

I CONVERTED A HALLICRAFTERS SR400 TO 6146s AND IT WORKED GREAT.MORE
OUTPUT ON 15 and 10mtrs.  
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Mark Foltarz
Sent: Saturday, February 18, 2006 4:26 PM
To: amradio@mailman.qth.net; [EMAIL PROTECTED]
Subject: [AMRadio] Replacing sweep tubes with 6146s

I picked up a Yaesu 570 ( predacessor to FT-101) at the Brooksville
hamfest
today. No finals.

I seem to remember a few years back an article on converting the finals
in a
FT-101* to 6146s.

Seems like a good idea now since a 6KD6 sweep tube cost a lot more than
a 6146.

Back when the tube rice boxes came out the sweep tubes could be had for
a
couple of bucks.

Anyone have thoughts on this potential conversion?

tnx

de KA4JVY

Mark



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RE: [AMRadio] Replacing sweep tubes with 6146s

[UVCM INC]

mark,
unless someone has a PROVEN swap out it is not a good idea.
Brad KB7FQR

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of Mark Foltarz
Sent: Saturday, February 18, 2006 1:26 PM
To: amradio@mailman.qth.net; [EMAIL PROTECTED]
Subject: [AMRadio] Replacing sweep tubes with 6146s


I picked up a Yaesu 570 ( predacessor to FT-101) at the Brooksville hamfest
today. No finals.

I seem to remember a few years back an article on converting the finals in a
FT-101* to 6146s.

Seems like a good idea now since a 6KD6 sweep tube cost a lot more than a
6146.

Back when the tube rice boxes came out the sweep tubes could be had for a
couple of bucks.

Anyone have thoughts on this potential conversion?

tnx

de KA4JVY

Mark



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RE: [AMRadio] Replacing sweep tubes with 6146s

[UVCM INC]

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of Mark Foltarz
Sent: Saturday, February 18, 2006 1:26 PM
To: amradio@mailman.qth.net; [EMAIL PROTECTED]
Subject: [AMRadio] Replacing sweep tubes with 6146s


I picked up a Yaesu 570 ( predacessor to FT-101) at the Brooksville hamfest
today. No finals.

I seem to remember a few years back an article on converting the finals in a
FT-101* to 6146s.

Seems like a good idea now since a 6KD6 sweep tube cost a lot more than a
6146.

Back when the tube rice boxes came out the sweep tubes could be had for a
couple of bucks.

Anyone have thoughts on this potential conversion?

tnx

de KA4JVY

Mark



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[AMRadio] Replacing sweep tubes with 6146s

[Mark Foltarz]

I picked up a Yaesu 570 ( predacessor to FT-101) at the Brooksville hamfest
today. No finals.

I seem to remember a few years back an article on converting the finals in a
FT-101* to 6146s.

Seems like a good idea now since a 6KD6 sweep tube cost a lot more than a 6146.

Back when the tube rice boxes came out the sweep tubes could be had for a
couple of bucks.

Anyone have thoughts on this potential conversion?

tnx

de KA4JVY

Mark



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Re: [AMRadio] Re: AM Transmitter Advice??

[George KB2Z]

If memory serves the diodes need to be configured push-pull for 
amplifier use and push-push if employed as an oscillator. . Its 
important to use a very noisy buffer in front the oscillator to cancel 
the hash inherent to the diodes.The second diode acts similar to a 
screen for steering



Phil Galasso wrote:

- Original Message -
From: "Bob Deuel" > Larry's tongue in cheek comment employing 866's as a
linear amplifier tube
  

prompted me to contribute the following: Certain full-wave rectifiers can


be
  

configured to amplify or oscillate. I have built audio, Hartley and


Simpson
  

oscillators using only 6AX5GT's full-wave rectifiers as the sole active
device. These were displayed at 2004 Mid-Atlantic Antique Radio Club Meet
and actually won a Blue Ribbon.



Could you get me a copy of the article or point me to a place where I could
get it. That is MOST interesting. I have seen vacuum tube diodes used as
noise generators (the 5722 comes to mind here), but I have never seen them
used as amplifiers or oscillators.

Phil K2PG


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Re: [AMRadio] AM Transmitter Advice??

[Brian Carling]

Hello Don!

Hey - mount those 6AG7s upside down in cooling oil and you 
can run 500 watts to 'em.  I wouldn't try it but I am sure 
SOMEONE has, LOL!

I am getting healthier! 73 de AF4K, Bry

On 18 Feb 2006 at 13:06, Rev. Don Sanders wrote:

> I like my 100 watt linear with four 6AG7"s.
> 
> Healthfully yours,
>   DON W4BWS

Re: [AMRadio] AM Transmitter Advice??

[Rev. Don Sanders]

I like my 100 watt linear with four 6AG7"s.

Healthfully yours,
  DON W4BWS
- Original Message - 
From: "Brian Carling" <[EMAIL PROTECTED]>
To: "Discussion of AM Radio" 
Sent: Friday, February 17, 2006 6:41 AM
Subject: RE: [AMRadio] AM Transmitter Advice??


> I bet you a BC610 will out-peg a DX100 any day!
> Don't care what the numbers say...
> 
> Grin!
> 
> That 12AX7 linear amplifier sounds like more of a FUN project 
> than a useful station accessory! Just WAIT until the experts 
> start telling you it can't be done, you will only get 30% 
> efficiency and all that jazz! LOL.
> 
> 73 de AF4K, Bry
> 
> On 17 Feb 2006 at 4:29, Jim Candela wrote:
> 
> > 
> > 
> > Hi All,
> > 
> >I recently had a conversation with a ham in San
> > Antonio (forgot his call), and he told me that he
> > built a unique linear amplifier for his central
> > electronics 10a, and for tubes he chose 3 type 12AX7
> > in parallel grounded grid. He said he could run 30
> > watts input (300v @ 100ma) with no problems, and about
> > 20 watts out. I find it odd though that a 10a can do
> > 10 watts with a single 6AG7, and 20 watts is only a
> > 3db boost. 
> > 
> > To my way of thinking, a linear amp needs to boost
> > your power at least 6 db (~1 'S' unit) to be worth the
> > trouble. For us AM'ers, going from 100 watts to 375
> > watts carrier does not meet the 6 db boost criteria,
> > and that explains why a good antenna on a DX-100 is
> > better than a average antenna on a Globe King 500.
> > 
> > Still, as I once posted last year, a dual 304TL
> > grounded grid linear seems to fit the bill as a 6 db
> > 'brick' capable of 400 watts AM carrier output with
> > 100 watts AM input, or said another way it takes 400
> > watts PEP and boosts it to 1600 watts PEP. There was
> > an old W6SAI construction project about this (single
> > 304tl GG amp), and I recall that the setup in class C
> > could run 1 kw dc input with over 1 kw rf output
> > because of the low gain, and massive amount of
> > feedthrough power from the exciter that finds it's way
> > to the output. This was a way around the FCC power
> > rules of the day.
> > 
> > Regards,
> > Jim
> > WD5JKO
> > 
> > --- Donald Chester <[EMAIL PROTECTED]> wrote:
> > 
> > > >Assuming one is going to build a linear, and so
> > > putting aside other issues
> > > >such as linear vs plate modulation, why do you
> > > think it makes a difference
> > > >what tube is used? Are you referring to running a
> > > linear at greater than
> > > >legal limit?.
> > > 
> > > Well, go ahead and try building a legal limit linear
> > > that runs a pair of 
> > > 807's in the final.
> > > 
> > >
> > ___
> > > 
> > > This message was typed using the DVORAK keyboard
> > > layout.  Try it - you'll 
> > > like it.
> > > http://www.mwbrooks.com/dvorak/
> > > http://gigliwood.com/abcd/
> > > 
> > > 
> > >
> > __
> > > AMRadio mailing list
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> > > Courson/wa3vjb
> > > 
> > 
> > __
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Re: [AMRadio] Re: AM Transmitter Advice??

[Phil Galasso]

- Original Message -
From: "Bob Deuel" > Larry's tongue in cheek comment employing 866's as a
linear amplifier tube
> prompted me to contribute the following: Certain full-wave rectifiers can
be
> configured to amplify or oscillate. I have built audio, Hartley and
Simpson
> oscillators using only 6AX5GT's full-wave rectifiers as the sole active
> device. These were displayed at 2004 Mid-Atlantic Antique Radio Club Meet
> and actually won a Blue Ribbon.

Could you get me a copy of the article or point me to a place where I could
get it. That is MOST interesting. I have seen vacuum tube diodes used as
noise generators (the 5722 comes to mind here), but I have never seen them
used as amplifiers or oscillators.

Phil K2PG