I have been reading the PEP discussion and where it is drifting.
Here's my thoughts. First, an amplifier with output devices (note-
tubes or solid state) will have a certain absolute maximum output
power capability. There is a point at which the tube(s) cannot produce
additional RF. If an attempt to exceed that level is made it
merely flat-tops and creates trash in addition to the desired signal.
That can be measured easily watching a 'scope and looking for the peaks.
You could just key down and go for maximum smoke.
Either method could be used to measure the output capability of an
amplifier.
However, to assume that PEP is 2 x key down is misleading. The
unit may not be capable of the 2 x level, see above. I guess this value
was derived when we started measuring output as opposed to DC input
with the advent of SSB.
It is misleading to assume that voice is symetrical, and peaks are
only 2x CW level. Having worked in broadcasting most of my life I can
attest to this. Look at some of the processing devices. SymmetriPeak,
early on device with a set of saturated coils hoping to
balance + & - levels of voice. Later it was noted FCC Rules had no max
for positive modulation. So we now "phased" mikes so all positive peaks were
in the same direction, only limiting negative peaks.
On and on the story goes. But for me amplifiers should be rated at there key
down
maximum, period. SSB can only be less total power, which results in good
sounding signals (no clipping). But, I submit to assume PEP is 2x CW and
assume the tubes can go that high is troublesome.
Ed K0KL
-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
Behalf Of amps-request@contesting.com
Sent: Tuesday, July 18, 2006 6:49 AM
To: amps@contesting.com
Subject: Amps Digest, Vol 43, Issue 70
Send Amps mailing list submissions to
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To subscribe or unsubscribe via the World Wide Web, visit
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When replying, please edit your Subject line so it is more specific
than "Re: Contents of Amps digest..."
Today's Topics:
1. Re: RF Chokes (GGLL)
2. Re: transformers (m.ford)
3. Re: transformers (Gary Schafer)
4. Question (Will Matney)
5. Life and gain of 3-500Z (Tom W8JI)
6. Re: RF Chokes (Tom W8JI)
7. Fw: transformers (m.ford)
8. Re: Tetrode Amplifier (m.ford)
----------------------------------------------------------------------
Message: 1
Date: Mon, 17 Jul 2006 23:31:39 -0300
From: GGLL <nagato@arnet.com.ar>
Subject: Re: [Amps] RF Chokes
To: Amplificadores Lineales <amps@contesting.com>
Message-ID: <44BC480B.8030604@arnet.com.ar>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I've always asked myself how could be rated for no resonances (in any
amateur
band) if the thing depends of the surrounding objects?.
Best regards
Guillermo - LU8EYW.
Bill Turner escribi?:
> FWIW, RF Parts sells a choke guaranteed to have no resonances in any
> HF band including WARC for $24.95.
>
> http://www.rfparts.com/choke.html#highrf
>
> Scroll down to RFC-3.
>
> Annoyingly, their minimum order is five cents higher than the price of
> this item. :-)
>
> Bill, W6WRT
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
------------------------------
Message: 2
Date: Mon, 17 Jul 2006 22:51:47 -0400
From: "m.ford" <k1ern@pioneerwireless.net>
Subject: Re: [Amps] transformers
To: "Gary Schafer" <garyschafer@comcast.net>
Cc: amps@contesting.com
Message-ID: <001501c6aa15$4d04e780$c3f55940@BASEOPS>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
----- Original Message -----
From: "Gary Schafer" <garyschafer@comcast.net>
To: "'m.ford'" <k1ern@pioneerwireless.net>
Cc: <amps@contesting.com>
Sent: Monday, July 17, 2006 9:37 PM
Subject: RE: [Amps] transformers
>
>
>> -----Original Message-----
>> From: m.ford [mailto:k1ern@pioneerwireless.net]
>> Sent: Monday, July 17, 2006 12:47 PM
>> To: Gary Schafer
>> Cc: amps@contesting.com
>> Subject: Re: [Amps] transformers
>>
>>
>> ----- Original Message -----
>> From: "Gary Schafer" <garyschafer@comcast.net>
>> To: "'m.ford'" <k1ern@pioneerwireless.net>; "'Tom W8JI'" <w8ji@w8ji.com>
>> Cc: <amps@contesting.com>
>> Sent: Monday, July 17, 2006 11:16 AM
>> Subject: RE: [Amps] transformers
>>
>>
>> >
>> >
>> >> As for PEP. I always felt it was a marketing term. Never bothered
with
>> it
>> >> and from the lengthy discussion here I have learned nothing new.
>> >
>> > How else would you measure SSB power if not PEP?
>> >
>> > 73
>> > Gary K4FMX
>> >
>> >
>> Hi Gary. Define the term "SSB power".
>>
>> Mike k1ern
>
> That's my question Mike.
>
> Rephrased; how would you rate the power output of an SSB transmitter? What
> units would you express the output power in?
>
> 73
> Gary K4FMX
>
>
Watts come to mind.
I think what you are trying to ask is how would I measure
the total power emitted from a transmitter that is modulated by single
sideband voice.
Two ways come to mind. First I would use a spectrum analyzer and crank up
the
persistance then measure the area under the curve. The rest is math. But
now you have to assume a bandwidth.
The second way would be to actually calculate and sum the area under each
envelope of each tone
produced and do it in real time. Oh, and while we are splitting hairs,
don't forget the carrier
suppression. A lot of ssb I hear, isn't.
As I recall, the advent of PEP brought us cross needle peak reading power
meters.
I think an artificial horizon indicator would yield more useable results.
Mike k1ern
>
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.1.394 / Virus Database: 268.10.1/389 - Release Date: 7/14/2006
>
>
------------------------------
Message: 3
Date: Tue, 18 Jul 2006 00:20:32 -0500
From: "Gary Schafer" <garyschafer@comcast.net>
Subject: Re: [Amps] transformers
To: "'m.ford'" <k1ern@pioneerwireless.net>
Cc: amps@contesting.com
Message-ID: <000101c6aa29$e51fded0$660fa8c0@YOURC36DD1B81E>
Content-Type: text/plain; charset="us-ascii"
> -----Original Message-----
> From: m.ford [mailto:k1ern@pioneerwireless.net]
> Sent: Monday, July 17, 2006 9:52 PM
> To: Gary Schafer
> Cc: amps@contesting.com
> Subject: Re: [Amps] transformers
>
>
> ----- Original Message -----
> From: "Gary Schafer" <garyschafer@comcast.net>
> To: "'m.ford'" <k1ern@pioneerwireless.net>
> Cc: <amps@contesting.com>
> Sent: Monday, July 17, 2006 9:37 PM
> Subject: RE: [Amps] transformers
>
>
> >
> >
> >> -----Original Message-----
> >> From: m.ford [mailto:k1ern@pioneerwireless.net]
> >> Sent: Monday, July 17, 2006 12:47 PM
> >> To: Gary Schafer
> >> Cc: amps@contesting.com
> >> Subject: Re: [Amps] transformers
> >>
> >>
> >> ----- Original Message -----
> >> From: "Gary Schafer" <garyschafer@comcast.net>
> >> To: "'m.ford'" <k1ern@pioneerwireless.net>; "'Tom W8JI'"
> <w8ji@w8ji.com>
> >> Cc: <amps@contesting.com>
> >> Sent: Monday, July 17, 2006 11:16 AM
> >> Subject: RE: [Amps] transformers
> >>
> >>
> >> >
> >> >
> >> >> As for PEP. I always felt it was a marketing term. Never bothered
> with
> >> it
> >> >> and from the lengthy discussion here I have learned nothing new.
> >> >
> >> > How else would you measure SSB power if not PEP?
> >> >
> >> > 73
> >> > Gary K4FMX
> >> >
> >> >
> >> Hi Gary. Define the term "SSB power".
> >>
> >> Mike k1ern
> >
> > That's my question Mike.
> >
> > Rephrased; how would you rate the power output of an SSB transmitter?
> What
> > units would you express the output power in?
> >
> > 73
> > Gary K4FMX
> >
> >
> Watts come to mind.
What kind of watts?
>
> I think what you are trying to ask is how would I measure
> the total power emitted from a transmitter that is modulated by single
> sideband voice.
> Two ways come to mind. First I would use a spectrum analyzer and crank up
> the
> persistance then measure the area under the curve. The rest is math. But
> now you have to assume a bandwidth.
You would also have to designate a given time for the measurement. Watt
seconds would be the result? You would also have to know the amount of
compression and the frequency content of the audio.
PEP seems a little more practical.
>
> The second way would be to actually calculate and sum the area under each
> envelope of each tone
> produced and do it in real time.
It seems that would be a necessity with your method.
>Oh, and while we are splitting hairs,
> don't forget the carrier
> suppression. A lot of ssb I hear, isn't.
Also amount of distortion products present would be necessary to know if you
are worried about carrier.
>
> As I recall, the advent of PEP brought us cross needle peak reading power
> meters.
> I think an artificial horizon indicator would yield more useable results.
>
> Mike k1ern
You seem to be saying that finding total average power over a given amount
of time would be the way to make the measurement. That would be highly
dependent on program material (voice frequency range, density, bandwidth
etc.) and would tell you little about the capabilities of a particular
transmitters power output abilities.
The peak reading wattmeter still seems the most practical of solutions from
what you have described.
73
Gary K4FMX
------------------------------
Message: 4
Date: Tue, 18 Jul 2006 01:31:08 -0400
From: "Will Matney" <craxd1@verizon.net>
Subject: [Amps] Question
To: amps@contesting.com
Message-ID: <200607180131080820.00709651@outgoing.verizon.net>
Content-Type: text/plain; charset=ISO-8859-1
All,
This I know is off topic, but I'm wondering what a B&K model E-200D RF
generator is worth now in good condition? This one has the manual/schematic,
test leads, and is complete with no damage. I know these are cheaper
generators, but I have the chance to buy one at I think a good price. Also,
I'd like to know any problems any have had with these from past users, etc.
I'm wanting to use this as a back up generator or use it where high
precision is not required (hobby, etc.). I have those type generators
already. Please reply off the list, and any comments are welcome.
Thanks,
Will
------------------------------
Message: 5
Date: Tue, 18 Jul 2006 06:14:21 -0400
From: "Tom W8JI" <w8ji@w8ji.com>
Subject: [Amps] Life and gain of 3-500Z
To: "k7rdx" <k7rdx@charter.net>, "Amps" <amps@contesting.com>
Message-ID: <000e01c6aa52$f4733930$640fa8c0@radioroom>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
> Agreed Tom...My question was why would someone run an amp
> with that value of
> line voltage if he knew the effect it would have on the
> fils.
The filament life issue is primarily an issue with good
manufacturing quality and steady operation at conservative
values.
Say you run a tube 24/7/52. In a week you have 168 hours. In
a year 8736 hours. There is no thermal cycling. There is no
time for the pin seals to get moist and oxidize ruining the
glass bond. There are no overtemperature operation or even
operation anywhere close to seal rating. The tube is
constantly being gettered. All we have is the filament
erroding away or losing emission from temperature. Emission
life is critical.
If we turn the amp on 3 hours a day, transmit 25% of the
time with varying power, let the thing sit for a week
without use once in a while, and occasionally run the seal
temps up to maximum, and use (by force now) poor quality
tubes we have a whole different set of likely failures. The
data points from and important to commercial service do not
apply the same way.
>I do know for a
> fact that a lot of the Chinese 3-500z tubes have higher
> gain than the older
> Eimacs
I'm not saying that isn't true, but I never saw that happen
at the transition time when Eimac went out of the glass
power grid business and I started looking at Chinese tubes.
I'm not trying to start another long argumentative thread
like the tube curve thread, but rather to learn something.
How did you measure gain and where did the tubes come from?
73 Tom
------------------------------
Message: 6
Date: Tue, 18 Jul 2006 06:15:45 -0400
From: "Tom W8JI" <w8ji@w8ji.com>
Subject: Re: [Amps] RF Chokes
To: "GGLL" <nagato@arnet.com.ar>, "Amplificadores Lineales"
<amps@contesting.com>
Message-ID: <001901c6aa53$26a605e0$640fa8c0@radioroom>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
I've always asked myself how could be rated for no
resonances (in any amateur
band) if the thing depends of the surrounding objects?.>>>
It can't possibly be rated that way.
73 Tom
------------------------------
Message: 7
Date: Tue, 18 Jul 2006 06:32:17 -0400
From: "m.ford" <k1ern@pioneerwireless.net>
Subject: [Amps] Fw: transformers
To: <amps@contesting.com>
Message-ID: <002301c6aa55$86b308a0$c3f55940@BASEOPS>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=response
----- Original Message -----
From: "m.ford" <k1ern@pioneerwireless.net>
To: "Gary Schafer" <garyschafer@comcast.net>
Sent: Tuesday, July 18, 2006 6:23 AM
Subject: Re: [Amps] transformers
>
> ----- Original Message -----
> From: "Gary Schafer" <garyschafer@comcast.net>
> To: "'m.ford'" <k1ern@pioneerwireless.net>
> Cc: <amps@contesting.com>
> Sent: Tuesday, July 18, 2006 1:20 AM
> Subject: RE: [Amps] transformers
>
>
>>
>>
>>> -----Original Message-----
>>> From: m.ford [mailto:k1ern@pioneerwireless.net]
>>> Sent: Monday, July 17, 2006 9:52 PM
>>> To: Gary Schafer
>>> Cc: amps@contesting.com
>>> Subject: Re: [Amps] transformers
>>>
>>>
>>> ----- Original Message -----
>>> From: "Gary Schafer" <garyschafer@comcast.net>
>>> To: "'m.ford'" <k1ern@pioneerwireless.net>
>>> Cc: <amps@contesting.com>
>>> Sent: Monday, July 17, 2006 9:37 PM
>>> Subject: RE: [Amps] transformers
>>>
>>>
>>> >
>>> >
>>> >> -----Original Message-----
>>> >> From: m.ford [mailto:k1ern@pioneerwireless.net]
>>> >> Sent: Monday, July 17, 2006 12:47 PM
>>> >> To: Gary Schafer
>>> >> Cc: amps@contesting.com
>>> >> Subject: Re: [Amps] transformers
>>> >>
>>> >>
>>> >> ----- Original Message -----
>>> >> From: "Gary Schafer" <garyschafer@comcast.net>
>>> >> To: "'m.ford'" <k1ern@pioneerwireless.net>; "'Tom W8JI'"
>>> <w8ji@w8ji.com>
>>> >> Cc: <amps@contesting.com>
>>> >> Sent: Monday, July 17, 2006 11:16 AM
>>> >> Subject: RE: [Amps] transformers
>>> >>
>>> >>
>>> >> >
>>> >> >
>>> >> >> As for PEP. I always felt it was a marketing term. Never bothered
>>> with
>>> >> it
>>> >> >> and from the lengthy discussion here I have learned nothing new.
>>> >> >
>>> >> > How else would you measure SSB power if not PEP?
>>> >> >
>>> >> > 73
>>> >> > Gary K4FMX
>>> >> >
>>> >> >
>>> >> Hi Gary. Define the term "SSB power".
>>> >>
>>> >> Mike k1ern
>>> >
>>> > That's my question Mike.
>>> >
>>> > Rephrased; how would you rate the power output of an SSB transmitter?
>>> What
>>> > units would you express the output power in?
>>> >
>>> > 73
>>> > Gary K4FMX
>>> >
>>> >
>>> Watts come to mind.
>>
>> What kind of watts?
>
> Watts is Watts. You can re-visit the argument about rms vs average
> but in the end Watts is Watts. I think you are coming dangerously close
> to another term that is used in certain circles. "talk power".
>
> Mike k1ern
>
>
>>
>>>
>>> I think what you are trying to ask is how would I measure
>>> the total power emitted from a transmitter that is modulated by single
>>> sideband voice.
>>> Two ways come to mind. First I would use a spectrum analyzer and crank
up
>>> the
>>> persistance then measure the area under the curve. The rest is math.
But
>>> now you have to assume a bandwidth.
>>
>> You would also have to designate a given time for the measurement. Watt
>> seconds would be the result? You would also have to know the amount of
>> compression and the frequency content of the audio.
>> PEP seems a little more practical.
>>
>>>
>>> The second way would be to actually calculate and sum the area under
each
>>> envelope of each tone
>>> produced and do it in real time.
>>
>> It seems that would be a necessity with your method.
>>
>>>Oh, and while we are splitting hairs,
>>> don't forget the carrier
>>> suppression. A lot of ssb I hear, isn't.
>>
>> Also amount of distortion products present would be necessary to know if
you
>> are worried about carrier.
>>
>>>
>>> As I recall, the advent of PEP brought us cross needle peak reading
power
>>> meters.
>>> I think an artificial horizon indicator would yield more useable
results.
>>>
>>> Mike k1ern
>>
>> You seem to be saying that finding total average power over a given
amount
>> of time would be the way to make the measurement. That would be highly
>> dependent on program material (voice frequency range, density, bandwidth
>> etc.) and would tell you little about the capabilities of a particular
>> transmitters power output abilities.
>>
>> The peak reading wattmeter still seems the most practical of solutions
from
>> what you have described.
>>
>> 73
>> Gary K4FMX
>>
>>
>>
>>
>>
>> --
>> No virus found in this incoming message.
>> Checked by AVG Free Edition.
>> Version: 7.1.394 / Virus Database: 268.10.1/389 - Release Date: 7/14/2006
>>
>>
------------------------------
Message: 8
Date: Tue, 18 Jul 2006 07:47:07 -0400
From: "m.ford" <k1ern@pioneerwireless.net>
Subject: Re: [Amps] Tetrode Amplifier
To: "Bob Maser" <bmaser@tampabay.rr.com>
Cc: amps@contesting.com
Message-ID: <001a01c6aa60$1688bc40$c3f55940@BASEOPS>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
----- Original Message -----
From: "Bob Maser" <bmaser@tampabay.rr.com>
To: "AMPS" <amps@contesting.com>
Sent: Saturday, July 15, 2006 11:57 AM
Subject: [Amps] Tetrode Amplifier
> Having just about completed my modifications on the Henry 4K-Ultra, I am
> looking for another amp project. I have a source for some 4CX300Y
tetrodes
> and I just bought some sockets for them. I am thinking about finding a
> desktop amp that was commercially produced using goofy tetrodes(or
triodes),
> no longer made, and relatively cheap that I could modify to use the
> 4CX400's. Any recommendations? The ideal amp would have enough room to
> install screen and bias supplies if it were originally a triode amp. I am
> thinking NCL-2000. Any out there?
>
> Thanks,
> Bob Maser W6TR
>
Hello Bob. Gee I almost missed this post. It was the NCL-2000 in caps
that caught me.
A gentleman that used to post here was involved in a lot of conversions
to 6 M for that amp. I guess he gutted them and started over. Wish I knew
it at the time because I would have inquired about the tailings. Actually I
did send an email but no joy.
I just qsyed to a new qth and have been setting up shop for a few weeks.
A few days ago I put all four working amps next to each other on the new
test bench.
I still need to un box the dead one. For a brief moment I was back in 1967
at the
factory on Washington street. Summer job. Then war.
I am sorry to hear that now there is new competition for a carcass. I always
wanted
to move the p/s outboard and stuff four 8122 in the same pretty box. Leave
the only
clue as new logo on the front that reads NCL-4000. The recent postings about
multitube
amps were very interesting with a lot of gotchas exposed. I took notes.
Cadavers can be had and brought back to life. The ones I see on ebay are
over priced. Lot of
strange looking mods too. I have seen more than one with the screen supply
brought
out to a fuse holder on the front panel. Useless front panel for my project.
You should be able to find a dead one local. "They are all dead until proven
otherwise."
Mike k1ern
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.1.394 / Virus Database: 268.10.1/389 - Release Date: 7/14/2006
>
>
------------------------------
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