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Re: Russian Doorknobs?

Harold Mandel
 

开云体育

Also look in <<? >>

?

Hal

?

From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of badgerscreek
Sent: Sunday, December 31, 2006 9:04 AM
To: ham_amplifiers@...
Subject: [ham_amplifiers] Russian Doorknobs?

?

Anyone offer opinions on the Russian Doorknobs used in plate blocking
applications?

I am interested in trying the KI5 types which are KVAR rated at 10 to
15 kv. There seem to be a bargain but i cant find RF current ratings
for them.

Greg
Re: Russian Doorknobs?

Harold Mandel
 

开云体育

Look in << >>

?

Hal

W4HBM

?

From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of badgerscreek
Sent: Sunday, December 31, 2006 9:04 AM
To: ham_amplifiers@...
Subject: [ham_amplifiers] Russian Doorknobs?

?

Anyone offer opinions on the Russian Doorknobs used in plate blocking
applications?

I am interested in trying the KI5 types which are KVAR rated at 10 to
15 kv. There seem to be a bargain but i cant find RF current ratings
for them.

Greg
Re: Russian Doorknobs?

Harold Mandel
 

开云体育

Some Russian ceramic capacitors will actually have their KVaR rating printed on them.

?

The print will have a number like “90#&.” The Cyrillic letters I forget, but

they do exist, as the caps will have their tolerance in %, voltage rating in KB

capacitance in another figure and amperage rating in another.

?

You know the cap will handle rf amperage when it states a current rating.

?

Hal

W4HBM

?

From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Jan Erik Holm
Sent: Sunday, December 31, 2006 9:22 AM
To: ham_amplifiers@...
Subject: Re: [ham_amplifiers] Russian Doorknobs?

?

Greg,

In my 8171 amp I use two Russian 470 pF caps in parallel for plate
blocking, dont remember if its the KI5 type but I could check ofcourse.

I know that I have seen some Russian capacitor data somewhere on
the internet but cant remember where.

Happy New Year / Jim SM2EKM
-----------------------------------------
badgerscreek wrote:
>
>
> Anyone offer opinions on the Russian Doorknobs used in plate blocking
> applications?
>
> I am interested in trying the KI5 types which are KVAR rated at 10 to
> 15 kv. There seem to be a bargain but i cant find RF current ratings
> for them.
>
> Greg
>

Re: Russian Doorknobs?

 

Greg,

In my 8171 amp I use two Russian 470 pF caps in parallel for plate
blocking, dont remember if its the KI5 type but I could check ofcourse.

I know that I have seen some Russian capacitor data somewhere on
the internet but cant remember where.

Happy New Year / Jim SM2EKM
-----------------------------------------
badgerscreek wrote:

Anyone offer opinions on the Russian Doorknobs used in plate blocking
applications?
I am interested in trying the KI5 types which are KVAR rated at 10 to
15 kv. There seem to be a bargain but i cant find RF current ratings
for them.
Greg
Re: AL80-A

[email protected]
 

Francis, we aren't gonna agree here. I'm retired so I don't have to sweat the issue of 8 bucks/hour. I'm retired and modestly comfortable. However, I made it on my on without someone looking over my shoulder. My feeling has always been that Unions are for people who can't cut it on their own. I never needed someone else to fight my battles for me. GL, 73


---- FRANCIS CARCIA <carcia@...> wrote:

Maybe you will get a chance to work for the that great company in the future. I hear $8 an hour buys a lot of amplifiers. Bet you would love to join a union if you were making that big $8. I hear cutting grass is a good business to get into. How about flipping burgers?
I drive buy this little machine shop that went out of business a while ago. We use to use them for rush jobs and they were cheap. Now we have to go far away and wait weeks
explain how smart that was.

"Mike(W5UC) & Kathy(K5MWH)" <w5uc@...> wrote:
Exactly correct. Unions have destroyed more US businesses than we can count by demanding more wages and benefits than the employer could stand, all with no regard for anyone but themselves. That's why I shop at Wal-Mart and admire them for standing up to Union pressure. I wonder if they want to go into the Ham amplifier business?

73,
Mike, W5UC

At 10:39 AM 12/29/2006, you wrote:

If the Wal-Mart business model had been discovered sooner and applied by more American businesses, there would be a lot more of them still in operation. The basic strategy followed by the major manufacturing companies was "Give the unions whatever they want no matter how unreasonable it may be and keep the lines running. We will just pass the additional cost along to the buyers."

One day some one came along who could make and sell it for less money.

David
KC2JD


-----Original Message-----

From: ham_amplifiers@... [ mailto:ham_amplifiers@...]On Behalf Of Harold Mandel

Sent: Friday, December 29, 2006 11:04 AM

To: ham_amplifiers@...

Subject: RE: [ham_amplifiers] Re: AL80-A


All you need to do is study the management philosophy and practices of WalMart.


WalMart dictates the selling price to their suppliers, and when they say to WalMart that they cannot


supply a product at what WalMart wants to pay, WalMart directs them to an overseas supplier of labor


or parts, or parts and labor. If the supplier wishes to stay in business they follow orders.


There are no television manufacturers left in America.


There were never, not one, ever, facsimile machine manufacturers in America.


American business has chosen to divert monies to volumetric production schemes to lower consumer prices

and to increase selling stock, and to increase cellular coverage for more immediate return on investment than


in research and development. The Japanese still devote a large portion of their manufacturing revenue into


R&D. That is why they have surpassed the United States.


Our cellular telephone providers would rather sink money into radio systems increasing bandwidth and coverage volume than they would on hardening the system with backup generators, towers that are not at the 85% windload factor and battery plants that serve anything more than noise filters, as it would take a 100% increase in capacity to afford any sort of uninterruptible backup.


Find out who goes to medical schools these days.


Is it our sons and daughters who have studied hard and achieved academic excellence in their


baccalaureate endeavors?


Or is it mostly off-shore students whose parents can afford to fund a chair?


Mike, you are entirely correct. RF amplifiers are too expensive to build here. Look at the latest


edition that was touted on the reflector. Kilobucks. Even the offshore amplifier companies are


outrageous, like Emtron. The Ameritron might be our last chance. Alpha sure won?t be the last bastion


because their targeted market is so narrow. It?s going to be Joe Ham that keeps Ameritron in the running,


and Ameritron will need to contend with the competition FROM China for the last remaining component resources as the supply dwindles.


Hal Mandel


W4HBM


---------------------------------


From: ham_amplifiers@... [ mailto:ham_amplifiers@...] On Behalf Of Mike(W5UC) & Kathy(K5MWH)

Sent: Friday, December 29, 2006 10:14 AM

To: ham_amplifiers@...

Subject: Re: [ham_amplifiers] Re: AL80-A


At 08:42 AM 12/29/2006, you wrote:


After WW-

II, Dr. Deming was invited to Japan to give lectures on how to go

about making high quality things that people will want to buy.



cheers, Jim


Isn't that amazing? And now American automobile mfrs wonder why the mind set in this country (including me) is to buy Japanese cars. Now GM is struggling to regain it's reputation, and the labor unions are still wanting to price themselves out of a job and GM out of the market.


I wonder what percentage of ham amplifier products are made in the US? If they are being made off-shore, how much labor would it cost to build a quality product. Did you ever wonder what happened to Hallicrafters & Hammarlund? If someone knows what caused the demise of these two I would like to hear the story. I still miss my HQ-129X. (No I didn't sell it. It went under in 6 feet of salt water in Hurricane Carla in 1961)


73,

Mike, W5UC






"age & treachery will overcome youth & skill"



"age & treachery will overcome youth & skill"
Re: Fax, Amps, Tapes, etc...

Harold Mandel
 

开云体育

Dear Mark,

?

Years and years ago I had the opportunity to work with John. …,

who held the 1934 patent on facsimile science.

?

The original telefaxes were drum types, and they actually

transmitted phoptos, were called “photofax” in the journalism

trade, etc., and these were made in the U.S., I agree.

?

However, in the ‘Sixties there were a couple of fax machines out

that used a rotating drum and stylus. The guts for these were made in

Switzerland (!).

?

Soon after, the Matsushita bought the patent from John (I will remember his

last name just after hitting “send”), and began manufacturing.

?

(I seem to recall the name John Shugard, and there was one other. They teamed up

later with Messrs. Hoffman, Reed and Solomon to develop the first mathematical

encryption formulae for compressing visual info, etc., etc.)

?

What made the very brief association with John Shugard interesting was that he was

a ham operator and our mutual interest in RTTY, using Kleinschmidt terminals

made for some great conversations.

?

(From the 20mA loop Gang…)

?

Hal Mandel

W4HBM

?

?

?

From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of AA6DX - Mark
Sent: Saturday, December 30, 2006 3:20 PM
To: ham_amplifiers@...
Subject: [ham_amplifiers] Fax, Amps, Tapes, etc...

?

AMPSHmmm .. re: fax machines never made in USA ... beg to differ on that
point ... Western Union's Deskfax, et al --- Way back, used to have a
contract for maintaining FAA fax machines, too... not from the Orient!
However .. having typed that .. find a VCR or Cassette machine or CD/DVD
player made in the US. One would think that with the relative simplicity of
an HF amplifier, and the by comparison immense weight, that it would be much
more profitable to manufacture in the US ... but, then, I go to Harbor
Freight and there are 200 pound widgets being sold for $29.95, so guess what
with container shipping freight costs are not an issue. Happy New Year,
all!
Mark Nelson - AA6DX
mailto: AA6DX@...

Fax, Amps, Tapes, etc...

 

AMPSHmmm .. re: fax machines never made in USA ... beg to differ on that
point ... Western Union's Deskfax, et al --- Way back, used to have a
contract for maintaining FAA fax machines, too... not from the Orient!
However .. having typed that .. find a VCR or Cassette machine or CD/DVD
player made in the US. One would think that with the relative simplicity of
an HF amplifier, and the by comparison immense weight, that it would be much
more profitable to manufacture in the US ... but, then, I go to Harbor
Freight and there are 200 pound widgets being sold for $29.95, so guess what
with container shipping freight costs are not an issue. Happy New Year,
all!
Mark Nelson - AA6DX
mailto: AA6DX@...
Re: AL80-A

Harold Mandel
 

Here's a ham radio link to the general discussion.



I'm right in the beginning of a tetrode project and working on the

steel chassis unit to house the outboard 2 amp power supply.



All the fans, blowers, plenum inlets and the tube socket will need a

4-1/2" hole. The easiest and least painful way to get these done, especially
in

military surplus steel, is to use a Greenlee/Textron 742BB knockout punch
that

retails for just around $500.00 apiece. Ouch! What are the alternatives? Use
a jig saw?

Use a boring bar? I didn't purchase the Chinese vertical knee mill being
thought about

two months ago because all the reviews say the Chinese and Taiwanese milling
machines

plainly suck, and I cannot afford a two-ton, $9K used Bridgeport, and don't
have a concrete

floor in my shop yet.



So I order the Greenlee/Textron punch. Made in the U.S.A. Shipped from
Atlanta.

Union made.



Three units later, they are still being shipped from Greenlee without
cushioning the

1-1/4" diameter drawbolt, and the other eight pounds of hardened steel
components

are smashing the threads so the drawnut jams on the threads and the nut
can't go forward, can't go

backward, and the threads are visibly dinged to where the black oxide
hardening finish is

wiped out and the thread geometry is bunged. Made in America.
Greenlee/Textron will

not talk on the telephone about this. The customer service people say to
raise the issue with the

distributor. There are no competitors for a 4-1/2" knockout punch.



Being in construction both professionally with the telephone company, et al,
and being a radio

builder for 38 years I have found that some tools work well, and Greenlee
was supposed to be

at the top of the food chain, albeit pricey. If you want a job done, though,
having the right

tools is so important. Doing conduit work in congested telephone central
offices is enough of a chore

because of the routing problems through the maze of stuff, and using cheesy
tools just makes

the day so much longer.



I don't know exactly how this relates to the tales of economic woe as
described in this chain,

but with so little being actually Made in U.S.A. is it not possible to
accentuate the quality to where

we might not be the top volume, but top quality?



The telephone company is getting rid of all the powerplant stuff tha was
made in America

and replacing it with stuff from China. Is this crazy? What happens when
China comes to the

realization that the U.S. phone system is powered by Chinese powerplants and
they decide to

say, "No more parts. So solly.?"



Hal

W4HBM



_____

From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of FRANCIS CARCIA
Sent: Saturday, December 30, 2006 10:29 AM
To: ham_amplifiers@...
Subject: RE: [ham_amplifiers] Re: AL80-A



Maybe you will get a chance to work for the that great company in the
future. I hear $8 an hour buys a lot of amplifiers. Bet you would love to
join a union if you were making that big $8. I hear cutting grass is a good
business to get into. How about flipping burgers?

I drive buy this little machine shop that went out of business a while ago.
We use to use them for rush jobs and they were cheap. Now we have to go far
away and wait weeks

explain how smart that was.

"Mike(W5UC) & Kathy(K5MWH)" <w5uc@...> wrote:

Exactly correct. Unions have destroyed more US businesses than we can count
by demanding more wages and benefits than the employer could stand, all with
no regard for anyone but themselves. That's why I shop at Wal-Mart and
admire them for standing up to Union pressure. I wonder if they want to go
into the Ham amplifier business?

73,
Mike, W5UC

At 10:39 AM 12/29/2006, you wrote:




If the Wal-Mart business model had been discovered sooner and applied by
more American businesses, there would be a lot more of them still in
operation. The basic strategy followed by the major manufacturing companies
was "Give the unions whatever they want no matter how unreasonable it may be
and keep the lines running. We will just pass the additional cost along to
the buyers."

One day some one came along who could make and sell it for less money.

David
KC2JD


-----Original Message-----

From: ham_amplifiers@... [
<mailto:ham_amplifiers@...>
mailto:ham_amplifiers@...]On Behalf Of Harold Mandel

Sent: Friday, December 29, 2006 11:04 AM

To: ham_amplifiers@...

Subject: RE: [ham_amplifiers] Re: AL80-A

All you need to do is study the management philosophy and practices of
WalMart.

WalMart dictates the selling price to their suppliers, and when they say to
WalMart that they cannot

supply a product at what WalMart wants to pay, WalMart directs them to an
overseas supplier of labor

or parts, or parts and labor. If the supplier wishes to stay in business
they follow orders.

There are no television manufacturers left in America.

There were never, not one, ever, facsimile machine manufacturers in America.

American business has chosen to divert monies to volumetric production
schemes to lower consumer prices

and to increase selling stock, and to increase cellular coverage for more
immediate return on investment than

in research and development. The Japanese still devote a large portion of
their manufacturing revenue into

R&D. That is why they have surpassed the United States.

Our cellular telephone providers would rather sink money into radio systems
increasing bandwidth and coverage volume than they would on hardening the
system with backup generators, towers that are not at the 85% windload
factor and battery plants that serve anything more than noise filters, as it
would take a 100% increase in capacity to afford any sort of uninterruptible
backup.

Find out who goes to medical schools these days.

Is it our sons and daughters who have studied hard and achieved academic
excellence in their

baccalaureate endeavors?

Or is it mostly off-shore students whose parents can afford to fund a chair?

Mike, you are entirely correct. RF amplifiers are too expensive to build
here. Look at the latest

edition that was touted on the reflector. Kilobucks. Even the offshore
amplifier companies are

outrageous, like Emtron. The Ameritron might be our last chance. Alpha sure
won't be the last bastion

because their targeted market is so narrow. It's going to be Joe Ham that
keeps Ameritron in the running,

and Ameritron will need to contend with the competition FROM China for the
last remaining component resources as the supply dwindles.

Hal Mandel

W4HBM


_____


From: ham_amplifiers@... [
<mailto:ham_amplifiers@...>
mailto:ham_amplifiers@...] On Behalf Of Mike(W5UC) &
Kathy(K5MWH)

Sent: Friday, December 29, 2006 10:14 AM

To: ham_amplifiers@...

Subject: Re: [ham_amplifiers] Re: AL80-A

At 08:42 AM 12/29/2006, you wrote:





After WW-

II, Dr. Deming was invited to Japan to give lectures on how to go

about making high quality things that people will want to buy.

<>
.org/wiki/W._Edwards_Deming

cheers, Jim



Isn't that amazing? And now American automobile mfrs wonder why the mind
set in this country (including me) is to buy Japanese cars. Now GM is
struggling to regain it's reputation, and the labor unions are still wanting
to price themselves out of a job and GM out of the market.

I wonder what percentage of ham amplifier products are made in the US? If
they are being made off-shore, how much labor would it cost to build a
quality product. Did you ever wonder what happened to Hallicrafters &
Hammarlund? If someone knows what caused the demise of these two I would
like to hear the story. I still miss my HQ-129X. (No I didn't sell it. It
went under in 6 feet of salt water in Hurricane Carla in 1961)

73,

Mike, W5UC






"age & treachery will overcome youth & skill"

<>
nk.net/pages/w5uc/

"age & treachery will overcome youth & skill"
<>
nk.net/pages/w5uc/
Re: Clipperton-L high input SWR

John Bednar
 

Rich,

Thanks.
** Hello, John == There should be one plate choke for
all 4 tubes.
Do you mean 4, R/L VHF parasitic suppressors?
Yes, sorry for the wording.

John
k3ct@...


-----Original Message-----
From: ham_amplifiers@...
[mailto:ham_amplifiers@...] On Behalf Of R L Measures
Sent: Saturday, December 30, 2006 9:53 AM
To: ham_amplifiers@...
Subject: Re: [ham_amplifiers] Clipperton-L high input SWR


On Dec 30, 2006, at 6:06 AM, John Bednar wrote:


Yes, equal brightness across all four tubes. The plate chokes on
each tube look fine also.
** Hello, John == There should be one plate choke for all 4 tubes.

Do you mean 4, R/L VHF parasitic suppressors?

The input SWR varies anywhere from 1.5:1 to >5:1 while I am tuning
the output. Is this expected?
** 1.5:1 is typical. >5:1 is not.

It causes the tuner in the Pro3 to
hunt for a better match. It's not oscillating.

Can I use my MFJ antenna analyzer with the amp turned off and
connected to the output to learn anything about the output tank?
** If one connects a 50-ohm load across the Load-C, one should
measure c. 2k-ohms at the input to the output Pi-network by
adjusting
the Tune and Load caps.
...
R. L. Measures, AG6K, 805.386.3734
r@..., rlm@..., www.somis.org






Yahoo! Groups Links
Re: AL80-A

FRANCIS CARCIA
 

Maybe you will get a chance to work for the that great company in the future. I hear $8 an hour buys a lot of amplifiers. Bet you would love to join a union if you were making that big $8. I hear cutting grass is a good business to get into. How about flipping burgers?
I drive buy this little machine shop that went out of business a while ago. We use to use them for rush jobs and they were cheap. Now we have to go far away and wait weeks
explain how smart that was.

"Mike(W5UC) & Kathy(K5MWH)" wrote:

Exactly correct. Unions have destroyed more US businesses than we can count by demanding more wages and benefits than the employer could stand, all with no regard for anyone but themselves.? That's why I shop at Wal-Mart and admire them for standing up to Union pressure. I wonder if they want to go into the Ham amplifier business?

73,
Mike, W5UC

At 10:39 AM 12/29/2006, you wrote:

If the Wal-Mart business model had been discovered sooner and applied by more American businesses, there would be a lot more of them still in operation.? The basic strategy followed by the major manufacturing companies was "Give the unions whatever they want no matter how unreasonable it may be and keep the lines running.? We will just pass the additional cost along to the buyers."
?
One day some one came along who could make and sell it for less money.
?
David
KC2JD
?
-----Original Message-----
From: ham_amplifiers@yahoogroups.com [ mailto:ham_amplifiers@yahoogroups.com]On Behalf Of Harold Mandel
Sent: Friday, December 29, 2006 11:04 AM
To: ham_amplifiers@yahoogroups.com
Subject: RE: [ham_amplifiers] Re: AL80-A
All you need to do is study the management philosophy and practices of WalMart.

WalMart dictates the selling price to their suppliers, and when they say to WalMart that they cannot

supply a product at what WalMart wants to pay, WalMart directs them to an overseas supplier of labor

or parts, or parts and labor. If the supplier wishes to stay in business they follow orders.

There are no television manufacturers left in America.

There were never, not one, ever, facsimile machine manufacturers in America.

American business has chosen to divert monies to volumetric production schemes to lower consumer prices
and to increase selling stock, and to increase cellular coverage for more immediate return on investment than

in research and development. The Japanese still devote a large portion of their manufacturing revenue into

R&D. That is why they have surpassed the United States.

Our cellular telephone providers would rather sink money into radio systems increasing bandwidth and coverage volume than they would on hardening the system with backup generators, towers that are not at the 85% windload factor and battery plants that serve anything more than noise filters, as it would take a 100% increase in capacity to afford any sort of uninterruptible backup.

Find out who goes to medical schools these days.

Is it our sons and daughters who have studied hard and achieved academic excellence in their

baccalaureate endeavors?

Or is it mostly off-shore students whose parents can afford to fund a chair?

Mike, you are entirely correct. RF amplifiers are too expensive to build here. Look at the latest

edition that was touted on the reflector. Kilobucks.? Even the offshore amplifier companies are

outrageous, like Emtron. The Ameritron might be our last chance. Alpha sure wont be the last bastion

because their targeted market is so narrow. Its going to be Joe Ham that keeps Ameritron in the running,

and Ameritron will need to contend with the competition FROM China for the last remaining component resources as the supply dwindles.

Hal Mandel

W4HBM

From: ham_amplifiers@yahoogroups.com [ mailto:ham_amplifiers@yahoogroups.com] On Behalf Of Mike(W5UC) & Kathy(K5MWH)
Sent: Friday, December 29, 2006 10:14 AM
To: ham_amplifiers@yahoogroups.com
Subject: Re: [ham_amplifiers] Re: AL80-A

At 08:42 AM 12/29/2006, you wrote:

After WW-
II, Dr. Deming was invited to Japan to give lectures on how to go
about making high quality things that people will want to buy.

cheers, Jim


Isn't that amazing?? And now American automobile mfrs wonder why the mind set in this country (including me) is to buy Japanese cars. Now GM is struggling to regain it's reputation, and the labor unions are still wanting to price themselves out of a job and GM out of the market.

I wonder what percentage of ham amplifier products are made in the US?? If they are being made off-shore, how much labor would it cost to build a quality product. Did you ever wonder what happened to Hallicrafters & Hammarlund? If someone knows what caused the demise of these two I would like to hear the story.? I still miss my HQ-129X. (No I didn't sell it.? It went under in 6 feet of salt water in Hurricane Carla in 1961)

73,
Mike, W5UC





"age & treachery will overcome youth & skill"


"age & treachery will overcome youth & skill"
Re: AL80-A

FRANCIS CARCIA
 

my Wife's best friend jost had his job out sourced to mexico to save a couple bucks on the lego toys. Maybe it will happen to you and you may catch my point. He has over 20 years with lego and 50 years old. The problem in this country today is nobody gives a crap about the next guy. Our economy shows it. BTW we now suck and would hate to see us go to war now that our manufacturing base is gone and most people don't know which end of a screw driver is the handle. Also I work hard for a living but would still pay more. I buy American every chance I get.

"Mike(W5UC) & Kathy(K5MWH)" wrote:

At 12:39 PM 12/29/2006, you wrote:
>I prefer to keep our money in America and have Americans working. So
>what if it costs more.

So what if it costs more? Give me a break! Some of you elitists may
be able to take that attitude, but the rest of us have to worry where
our money goes. If I took that attitude I would have to forget Amateur Radio.
I'm happy you are so flush.

73,
Mike, W5UC
"age & treachery will overcome youth & skill"
Re: Clipperton-L high input SWR

 

On Dec 30, 2006, at 6:06 AM, John Bednar wrote:


Yes, equal brightness across all four tubes. The plate chokes on
each tube look fine also.
** Hello, John == There should be one plate choke for all 4 tubes. Do you mean 4, R/L VHF parasitic suppressors?

The input SWR varies anywhere from 1.5:1 to >5:1 while I am tuning
the output. Is this expected?
** 1.5:1 is typical. >5:1 is not.

It causes the tuner in the Pro3 to
hunt for a better match. It's not oscillating.

Can I use my MFJ antenna analyzer with the amp turned off and
connected to the output to learn anything about the output tank?
** If one connects a 50-ohm load across the Load-C, one should measure c. 2k-ohms at the input to the output Pi-network by adjusting the Tune and Load caps.
...
R. L. Measures, AG6K, 805.386.3734
r@..., rlm@..., www.somis.org
Re: Clipperton-L high input SWR

John Bednar
 

Yes, equal brightness across all four tubes. The plate chokes on
each tube look fine also.

The input SWR varies anywhere from 1.5:1 to >5:1 while I am tuning
the output. Is this expected? It causes the tuner in the Pro3 to
hunt for a better match. It's not oscillating.

Can I use my MFJ antenna analyzer with the amp turned off and
connected to the output to learn anything about the output tank?

John
k3ct@...

-----Original Message-----
From: ham_amplifiers@...
[mailto:ham_amplifiers@...] On Behalf Of R L Measures
Sent: Saturday, December 30, 2006 6:51 AM
To: ham_amplifiers@...
Subject: Re: [ham_amplifiers] Clipperton-L high input SWR


On Dec 29, 2006, at 6:40 PM, John Bednar wrote:


I am working on a friend's Clipperton-L that suffers from poor
input
swr (3:1, usually greater). I have spent many hours working on
this
amp and I am stumped. I would appreciate suggestions
Reportedly the amp has new tubes in it (Taylor). It has the 10m
modification and the additional doorknob caps recommended on VE3NH
webpage. It has 30 to 50ma of idling plate current only when the
amp
is keyed.
Are all 4 filaments lit?

...
R. L. Measures, AG6K, 805.386.3734
r@..., rlm@..., www.somis.org






Yahoo! Groups Links
Re: Clipperton-L high input SWR

 

On Dec 29, 2006, at 6:40 PM, John Bednar wrote:


I am working on a friend's Clipperton-L that suffers from poor input
swr (3:1, usually greater). I have spent many hours working on this
amp and I am stumped. I would appreciate suggestions
Reportedly the amp has new tubes in it (Taylor). It has the 10m
modification and the additional doorknob caps recommended on VE3NH
webpage. It has 30 to 50ma of idling plate current only when the amp
is keyed.
Are all 4 filaments lit?

...
R. L. Measures, AG6K, 805.386.3734
r@..., rlm@..., www.somis.org
Re: Drake L-7 Negative Grid Current

 

On Dec 29, 2006, at 8:09 PM, Garry wrote:



R L Measures wrote:



On Dec 29, 2006, at 2:05 PM, Garry wrote:

Good Evening,

I was operating on 20 meters this afternoon with my L-7 on the SSB
mode.
Everything was normal for about an hour. Then I noticed in the
middle of
a QSO, the grid current meter started going into negative
territory
against the left side of it's case and plate current rising above
normal. I could also smell something unusual but could not confirm
if it
was coming from the power supply or RF deck. I put the amp in
standby
mode to check meter readings and monitored plate voltage and
current
which were normal, then shut it off. There was no spark, flash,
or any
other indication of abnormality other than the unusual smell of
something possibly overheating. The smell went away shortly after
powering down the amp.

I've heard of this condition before but can't remember where the
problem
was.
This can be the result of a parasitic arc to ground. Do you have
access to a dip-meter?
I have an MFJ-269 Analyzer, but no dip meter.
RR

A week earlier the power supply blew the .82 ohm fuse in the B+
line. When I had the supply apart to replace this, I also
removed the
two 50K ohm 50 watt and 5K ohm 7 watt resistors and placed a 25
ohm 50
watt "glitch" resistor in series with B+ just ahead of the .82 ohm
resistor fuse I replaced.

I also placed a string of 10 1N5408 diodes in series with a
100K ohm 3
watt MOF(TR relay shorts 100K R on transmit) to lower the tube
bias
and
all was working normal until this happened today. This mod and
others
for Drake amps has been fully documented here.

Does anyone have an suggestions on where the problem may be?
Perhaps one tube has a grid-filament short that only happens when
the
tube is hot? A high-potential tester will find this problem when the
tube is cold. If the filament-grid breakdown potential is under 5000
volts, the filament helices are likely bent and the tube may short
when it is hot.
I don't have a way to test the tubes other than a DMM. Unless the tube
shows a short when cold, I don't know of another way to test with what I
have available.
Garry === I high-pot tubes for $0.00 if the sender pays the return postage.

R. L. Measures, AG6K, 805.386.3734
r@..., rlm@..., www.somis.org
Re: Drake L-7 Negative Grid Current

Garry
 

pentalab wrote:
--- In ham_amplifiers@... <mailto:ham_amplifiers%40yahoogroups.com>, Garry <g.drummond@...> wrote:
>
> Good Evening,
>
> I was operating on 20 meters this afternoon with my L-7 on the SSB
mode.
> Everything was normal for about an hour. Then I noticed in the
middle of
> a QSO, the grid current meter started going into negative
territory
> against the left side of it's case and plate current rising above
> normal. I could also smell something unusual but could not confirm
if it
> was coming from the power supply or RF deck. I put the amp in
standby
> mode to check meter readings and monitored plate voltage and
current
> which were normal, then shut it off. There was no spark, flash, or
any
> other indication of abnormality other than the unusual smell of
> something possibly overheating. The smell went away shortly after
> powering down the amp.
>
> I've heard of this condition before but can't remember where the
problem
> was. A week earlier the power supply blew the .82 ohm fuse in the
B+
> line. When I had the supply apart to replace this, I also removed
the
> two 50K ohm 50 watt and 5K ohm 7 watt resistors and placed a 25
ohm 50
> watt "glitch" resistor in series with B+ just ahead of the .82 ohm
> resistor fuse I replaced.
>
> I also placed a string of 10 1N5408 diodes in series with a 100K
ohm 3
> watt MOF(TR relay shorts 100K R on transmit) to lower the tube
bias and
> all was working normal until this happened today. This mod and
others
> for Drake amps has been fully documented here.
>
>
> Does anyone have an suggestions on where the problem may be?
### Gary. Carefully take it apart... and see what was over
heating in there 1st.... and see if in HV supply box.... or RF
deck. If it was a grid to fil short..... try the tubes.... ONE
at a time. I'd remove BOTH tubes 1st.... then fire up the amp..
and see if plate V normal, etc...... then shut it down.... let bleed
down... then install just one tube.
### were u in the low plate V position when this happened [cw
position 1900 v no load]... or ssb 2700V HV position ?
SSB mode(2700V). As soon as I saw it I switched the amp to standby mode and checked the plate voltage which was normal as I normally monitor grid current, then switched to CW mode and Plate V dropped to approx 1900V & zero plate current. I then turned it off.
## I doubt it's a parasitic of any sort... since the plate V is low
on the L7 anyway.
### Between trying the tubes one at a time.. and also moving the one
tube from one socket to the other... and also toggling between low
plate V and high plate V... u should be able to narrow it down
quite a bit.
## Neg grid current is usually a grid to fil short... on at least
one tube.
### Is it pulling normal idle current on cw/ssb ? [compared to when
u 1st put the 10 x diodes in the ct]
I'll check this out. I've got to do some office work this weekend and may not get to work on it until next week. Was working a VK4 when it happened. I received a good RS report for a 135' dipole fed with ladder line & tuner.

Thanks,
Garry
Later... Jim VE7RF

>
> Thanks,
> Garry - WR4R
>
Re: Drake L-7 Negative Grid Current

Garry
 

R L Measures wrote:
On Dec 29, 2006, at 2:05 PM, Garry wrote:

> Good Evening,
>
> I was operating on 20 meters this afternoon with my L-7 on the SSB
> mode.
> Everything was normal for about an hour. Then I noticed in the
> middle of
> a QSO, the grid current meter started going into negative territory
> against the left side of it's case and plate current rising above
> normal. I could also smell something unusual but could not confirm
> if it
> was coming from the power supply or RF deck. I put the amp in standby
> mode to check meter readings and monitored plate voltage and current
> which were normal, then shut it off. There was no spark, flash, or any
> other indication of abnormality other than the unusual smell of
> something possibly overheating. The smell went away shortly after
> powering down the amp.
>
> I've heard of this condition before but can't remember where the
> problem
> was.
This can be the result of a parasitic arc to ground. Do you have
access to a dip-meter?
I have an MFJ-269 Analyzer, but no dip meter.

> A week earlier the power supply blew the .82 ohm fuse in the B+
> line. When I had the supply apart to replace this, I also removed the
> two 50K ohm 50 watt and 5K ohm 7 watt resistors and placed a 25 ohm 50
> watt "glitch" resistor in series with B+ just ahead of the .82 ohm
> resistor fuse I replaced.
>
> I also placed a string of 10 1N5408 diodes in series with a 100K ohm 3
> watt MOF(TR relay shorts 100K R on transmit) to lower the tube bias
> and
> all was working normal until this happened today. This mod and others
> for Drake amps has been fully documented here.
>
> Does anyone have an suggestions on where the problem may be?
Perhaps one tube has a grid-filament short that only happens when the
tube is hot? A high-potential tester will find this problem when the
tube is cold. If the filament-grid breakdown potential is under 5000
volts, the filament helices are likely bent and the tube may short
when it is hot.
I don't have a way to test the tubes other than a DMM. Unless the tube shows a short when cold, I don't know of another way to test with what I have available.
>
> Thanks,
> Garry - WR4R
>
>
>
R. L. Measures, AG6K, 805.386.3734
r@... <mailto:r%40somis.org>, rlm@... <mailto:rlm%40somis.org>, www.somis.org
Clipperton-L high input SWR

John Bednar
 

I am working on a friend's Clipperton-L that suffers from poor input
swr (3:1, usually greater). I have spent many hours working on this
amp and I am stumped. I would appreciate suggestions.

Reportedly the amp has new tubes in it (Taylor). It has the 10m
modification and the additional doorknob caps recommended on VE3NH
webpage. It has 30 to 50ma of idling plate current only when the amp
is keyed.

The efficiency is less than 50%, with 100W of drive the plate
current is about .5A, loaded voltages are 1600V (cw)/ 2400V (ssb).
When I first test the amp, I couldn't get any more than ~450 watts
output with 100 watts of drive.

I have disconnected the ALC circuit, removed or isolated and
measured all 0.01uf caps on the tubes, measured the series caps on
the input, removed RF-3 and measured the resistance (~30-40 ohms),
bypassed the TR relay running new coax cables directly to the input
and output all with no improvement to the input SWR.

During the last two days I have concentrated on 15m since few of the
doorknob caps are used and most of the band switch contacts are
unused.

The output has gone up a little since the cover was removed and the
TR relay bypassed. On 15m, the maximum output on 15m is now is
around 650W output with 100W of drive. The input swr is greater than
3:1. I am using the tuner in the radio but sometimes it drops out
because it can't be matched.

When I change from Vp 1600V (cw) to 2400V (ssb) (loaded voltages)
the output doesn't change very much (50 to 90 watts). I also have
noticed that the input SWR changes when I am tuning the amp but the
minimum swr does not occur where the amp output is at maximum.

I have tried one tube and two tubes in the amp but the input SWR is
worse. The amp is very clean inside, surprisingly clean. I have
checked and rechecked for faulty solder joints.

Does anyone have any suggestion what to try next?

John
k3ct@...
Heathkit HA-10 Warrior meter problem

cqkg8co
 

I have a HA-10 Warrior that is working well in most respects, however,
there is an issue with the meter.

The meter will show HV, however, when I want to look at the grid or the
plate, the meter drops to 0.

I have put deoxit on the multi function switch, but that didn't seem to
do anything.

Any suggestions would be appreciated.

Thank You


Brian, KG8CO
Re: Drake L-7 Negative Grid Current

pentalab
 

--- In ham_amplifiers@..., Garry <g.drummond@...> wrote:

Good Evening,

I was operating on 20 meters this afternoon with my L-7 on the SSB
mode.
Everything was normal for about an hour. Then I noticed in the
middle of
a QSO, the grid current meter started going into negative
territory
against the left side of it's case and plate current rising above
normal. I could also smell something unusual but could not confirm
if it
was coming from the power supply or RF deck. I put the amp in
standby
mode to check meter readings and monitored plate voltage and
current
which were normal, then shut it off. There was no spark, flash, or
any
other indication of abnormality other than the unusual smell of
something possibly overheating. The smell went away shortly after
powering down the amp.

I've heard of this condition before but can't remember where the
problem
was. A week earlier the power supply blew the .82 ohm fuse in the
B+
line. When I had the supply apart to replace this, I also removed
the
two 50K ohm 50 watt and 5K ohm 7 watt resistors and placed a 25
ohm 50
watt "glitch" resistor in series with B+ just ahead of the .82 ohm
resistor fuse I replaced.

I also placed a string of 10 1N5408 diodes in series with a 100K
ohm 3
watt MOF(TR relay shorts 100K R on transmit) to lower the tube
bias and
all was working normal until this happened today. This mod and
others
for Drake amps has been fully documented here.


Does anyone have an suggestions on where the problem may be?

### Gary. Carefully take it apart... and see what was over
heating in there 1st.... and see if in HV supply box.... or RF
deck. If it was a grid to fil short..... try the tubes.... ONE
at a time. I'd remove BOTH tubes 1st.... then fire up the amp..
and see if plate V normal, etc...... then shut it down.... let bleed
down... then install just one tube.

### were u in the low plate V position when this happened [cw
position 1900 v no load]... or ssb 2700V HV position ?

## I doubt it's a parasitic of any sort... since the plate V is low
on the L7 anyway.

### Between trying the tubes one at a time.. and also moving the one
tube from one socket to the other... and also toggling between low
plate V and high plate V... u should be able to narrow it down
quite a bit.

## Neg grid current is usually a grid to fil short... on at least
one tube.

### Is it pulling normal idle current on cw/ssb ? [compared to when
u 1st put the 10 x diodes in the ct]



Later... Jim VE7RF





Thanks,
Garry - WR4R
39321 - 39340 of 41137