Peter & Jim,

I started using a thick fish paper and paper tubing like that used for RF
coils. You can buy it in larger diameters. I tried some with some 4CX250B's
just to see how it worked and it was ok. The tubing is made from an
electrical insulation type paper. The fish paper sheets is the blue or gray
type, and about 1/6" thick. It's the same stuff you can make transformer
bobins with. The tubes don't get hot enough to do anything to the paper,
including the larger tubes if the air is flowing. The paper tubing is made
by Precision Paper Tube. They supply the electrical/electronics industry.
Oceanstate Electronics has the fish paper. A Google search will quickly find
both.

Best,

Will

All,

I have the following four pieces of test equipment for sale;

(1) Model 1020-B Megohm Meter by Freed Transformer
1 meg to 100k meg

(2) Model 404M3 "Hypot" by Associated Research
4 kV @ 100w

(3) Model 3050 sine/square wave generator by B&K Instruments

(4) Model 3500 5-1/2 digit DMM by Data Precision

I bought these with some other equipment and was going to
overhaul each. I've not had the chance to thoroughly test
each, and already have other equipment like this, so I'm
going to sell these cheap as a lot. The cost for the lot
is $75 US Plus shipping. Postal money order prefered.
Please e-mail me at: craxd1 at verizon.net

Thanks,

Will

Hi Jim,

I use heatresistant glass cylinders I get made locally and also use
round teflon covers as you, thats works very well.
All my blowers are made by EBM.
I do not like to boost a tubes rating, I rather prefer then to use a
bigger one.
I prefer that my GG amps cannot run in too high dissipation at full
drive. They should have no problem when the antenna gets lost...

73
Peter


--- In ham_amplifiers@..., "pentalab" <jim.thomson@...>
wrote:

For an experiment, I remember W7IUV had fabricated a >fiberglass
box around his YC-156.. for a chimney.

We tried the same trick... except the vertical sidewalls were
made from wood... about 9" square... top was also made from
wood.... and the original chimney was placed in a groove.. on
top of this wooden affair. Now we could increase the hole
sizes on the chassis.

The result was a huge improvement! Intead of the original 205
cfm... we are now getting an easy 320 cfm [using a Dayton
5C508 dual speed, capacitor start blower].

I've heard that Emtron is selling their softstarter as a seperate

item.

This softstarter is a small switcher which chops the AC voltage,

by doing

so limiting the inrush current.

Seems to me like the inrush shock to the PS lasts well more than
1/180th of a second (2 crossings every full 60 Hz cycle). If their
step-start uses SS zero-crossing devices, that means full current is
applied 90 degrees (+/- PF) after the moment the ON button is pressed.
That's an awfully large amount of current in a very short period of
time.

Unless there's some documented evidence that proves current is
reasonably limited with the use of these SS crossing devices, I think
I'll stick to relays and power resistors.

Paul, W9AC

Tom,

If the board isn't damaged (traces burnt off), I'd just repair it.
I'd think that would be the cheaper way to go. First thing I'd do
is to make sure the lightning didn't short out the power transformer(s).
If it did, your going to be into some cost. At that, it may be better
to just sell it off and try to get your money back, unless you want
to repair it. It's a matter of what the cost is as compared to the
worth of the amp, plus if you want to do that amount of work. The
L7 if I recall does sell pretty high on ebay starting at around
($800 plus).

Best,

Will

Since Eimac never made a chimney for either a 3CX-3000A7 or a
3CX-6000A7 [or the socket] several after market chimneys have
appeared.

I purchased the one for the 6000A7. It was solid 1/4" thick
teflon... straight up and down, no flanges.... and it's weight
held it to the chassis. 6.130" ID 6.630" OD

We found that this restricted the airflow up from the chassis
too much. [both the ceramic 'stem' on the 3000/6000 are
identical.. and much smaller diam than a YC-156 or a 10,000A7. ]

For an experiment, I remember W7IUV had fabricated a fiberglass
box around his YC-156.. for a chimney.

We tried the same trick... except the vertical sidewalls were
made from wood... about 9" square... top was also made from
wood.... and the original chimney was placed in a groove.. on
top of this wooden affair. Now we could increase the hole
sizes on the chassis.

The result was a huge improvement! Intead of the original 205
cfm... we are now getting an easy 320 cfm [using a Dayton
5C508 dual speed, capacitor start blower].

On the next chimney... we will toss the after market straight
up and down chimney... and just increase the vertical sides of
the box... and use a solid teflon top lid.. with a 6.130" hole in
it.

This technique can be used on any metal tube. The after
market chimney's for the 3000A7 [4.130" ID] restrict the
air too much as well. On one 3000A7 project... I used a SK-
306.. designed for a 4CX-5000A7.. which is a bit too big a diam at
the top.... so we filled the gap.. by wrapping a few layers of
silicone rubber around the tube.. held in place by a SS hose
clamp... worked good. ... since the SK-306 chimney has a flared
out base.


Eimac specs the 6000A7 for 205 cfm of air. [based on a 50
deg C /121 deg F inlet air temp.]

With 320+ cfm... and an inlet air temp of 25 deg C..... we
calculated the anode diss is now an easy 8500+ Watts !

Talk about the sleeper of the year. This tube is real easy to
increase it's stock anode dissipation. The secret is the small
diam ceramic 'stem',makes for larger fins underneath...
compared to a say 5000A7/YC-156..... which has a huge
diam 'stem'... and a smaller anode cooler.



The Dayton 5C508 blower is a dual speed 1100 rpm /1450 rpm
unit. Comes with a single oil filled start cap. The over
temp protected motor is partially embedded in one end. It
draws intake air from both ends. With no back pressure... in
free air, it's 765 cfm on high speed..... and down to 320
cfm @ .9" water pressure.

They installed clip weights to some of the impellor blades.... so
it's perfectly balanced from the factory... like balancing a car
wheel.

Later..... Jim VE7RF

Bill,

I don't have one now, and haven't since the early 80's when I used it for a
whole 9 monts if that (Novice). However, I think everyone that was on the
Amps mailer knows what happened in my case so it's kind of a moot point.
I'll get one again if the rule changes that supposed to happen eventually
do, and to my liking. I made a promise back then in the 80's due to a good
friend, and I've kept it up to this date.

Best,

Will

Jim,

What you describe may help a little. The problem is the internal connection
from the ring to the grid itself, and it's size. If it's only a piece of
wire, you may not gain anything as the wire would be the bottleneck I would
think. The ring would help a little by being a larger heatsink for the
connection itself, but the grid itself is still wire which it's size and
coating (gold, etc) can only take so much current. The ring would have to
dissapate the heat from the grid via the internal connection(s).

Best,

Will

From: ham_amplifiers@... [mailto:ham_amplifiers@yahoogroups.

com]

On Behalf Of pentalab
Sent: Donnerstag, 21. September 2006 22:12
To: ham_amplifiers@...
Subject: [ham_amplifiers] Re: Can Grid Dissipation in metal GG triodes be
increased ????



--- In ham_amplifiers@ <mailto:ham_amplifiers%40yahoogroups.com>
yahoogroups.com, "pentalab" <jim.thomson@>
wrote:

Gents

On these 3CX-6000's and also the socketless version [ YC-

243],

I fool with from time to time, Eimac/ Svetlana state's the

grid

diss at 225 Watts CCS. [3CX-3000A7 is also 225 w CCS grid]

Now, since the tube(s) can be operated in either GG OR grid
driven.... it occured to me that in grid driven mode... the grid
should still has a 225 w CCS rating ???

The point here is..... in GG service... you bolt this huge grid
ring to the chassis.... and in the case of the socketless
version.... an even bigger diam grid flange is bolted to the
chassis !

Now... that alone should heatsink the grid ??? Since the

grid

is sitting in a vac... the only way for thermal heat to escape is
via the grid flange.

Since the below chassis compartment is pressurized... one might
think the actual grid dissipation can perhaps be increased

via

this heatsink action ?? [GG mode]

Am I out to lunch here ???

Later..... Jim VE7RF

### Did anybody actually read the above ???

Later.... Jim VE7RF

ORIGINAL MESSAGE:

On Thu, 21 Sep 2006 21:17:29 -0000, "badgerscreek" <qrp73@...>
wrote:

The most annoying thing about ham groups is the request for a
callsign. Now since when do you need a callsign to use the internet?,

------------ REPLY FOLLOWS ------------

I'm automatically suspicious of a poster without a callsign unless
they come right out and say why they don't. Most hams are proud of
theirs and anyone who isn't is... suspect. Do you have one?

Bill, W6WRT

Jim,

See below.

--- In ham_amplifiers@..., "pentalab" <jim.thomson@...>
wrote:

--- In ham_amplifiers@..., "RICHARD GEORGE" <k6kwq@>
wrote:

It's also funny that when I asked on the amps reflector if Rich

had been kicked off, Tom wrote back to me the reasons he was kicked
off for, before it ever showed up on the reflector that he was gone.
The admin guy didn't answer me until the next day. If the admin guy
is not Tom, then he must be helping the admin guy censor.

### Now this just cracks me up !! Were the reasons that
Tom gave you.. identical to the "official" ones on the now
defunct ..'amps' ????

What happened, and you may well know this, was that when Tom first
came back on the mailer, Rich and myself collared him on several
topics he was really wrong on. When we done this, the unknown
moderator placed Rich and myself on moderation. The lazy b@st##d would
only post Rich or my replies maybe twice a day either early in the
morning, or late at night. What brought the thing to a head for me was
Toms reply to me about how to figure the rms current needed by a
transformer from a bridge rectifier with capacitor input circuit. Tom
had replied that I was wrong, so my next post proved me correct, with
a link to Hammond Transformer showing the same formula. This unknown
moderator would NOT release my reply to the list because I proved Tom
wrong. I then took the advice of Rich and started going around this
moderator by direct mail. That's when it came out on the mailer about
"harvesting e-mail addresses" which I never did. I did however send
that reply for Tom to almost everyone in my address book. The
moderator really got pissed about this. He finally took me off
moderation about a week later, but did not Rich. Next, he silently
banned Rich from the group, and a member posted about Rich being
banned. The rest is history.

I also received a very bitterly written e-mail from this unnammed
moderator about Rich and myself. I have to say, it was to the point of
liable. The rant sounded a lot like Tom by the words and expressions
used in the text. I then e-mailed the letter to Rich and a few others
who wanted to see it. That's when we first started wondering if the
moderator wasn't Tom.

### I also noticed that once the dust settled... that W8JI is
back at it again...... posting left, right and center...
on 'amps' !!

Yup, and the shame is that ones not knowing any better will believe
some of the theory he's just plain wrong on. I finally added Tom to my
junk mail filter and his posts end up in the waste basket in my e-mail
application. I noticed he was really taking off as my junk mail folder
really grew in the past 1-2 days, all from Tom.

### some poor fellow wants to build a hb tube amp.
Tom.. 'suggests' he build a 12 vdc SS device.

Talk about splatter without using a filter, and the guy will be extra
good friends with his neighbors.

### If Tom Rauch is not the admin/censor of 'amps'..... then
he's certainly joined at the hip of whoever is... or has a huge
influence over the ...."mystery censor" .

AMEN!!!!!!!!!

### Rich tells me... that the mega mailing list is now defunct
on 'amps'. To me... that's the straw that broke the camels
back.

### IMO... 'amps' has just degenerated into a ... "Tom Rauch
knows everything soapbox/platform"

Exactomundo!

## In the past..... anybody who didn't have a callsign got
booted from 'amps'...... ditto with some very knowledeable
11m amp builders...... and also Carl, KM1H.... who was a wealth
of practical info.

Yup, the moderator said in his e-mail that since I didn't post a call
sign, and used to build illegal amps back in the 80's, he gave me
plenty of leway. I had to laugh as he didn't post a name nor a call
sign himself!

Ed Dullaney who owned D&A Manufacturing was who talked me into the
business right before he passed away (Actually two others did to which
will remain nameless). We became good friends and spoke a lot on the
phone. Ed actually was a teacher at a Vo Tech, and was an instructor
for an electrical corrospondence school. He used to be pictured in
some ads for the corrospondence school in some old electronics
magazines. Ed was also a Ham by the way, and knew a great deal about
amplifier design. I like him give my hard earned knowledge of amp
design free to anyone who asks. Just because we built illegal amps at
one time doesn't mean we can't offer free knowledge to others.

### who ever designed the undersized tank coils in the AL-80B
was a complete idiot imo. The wire ga is the same size as
what's used in a 200 w Drake T4XC TX.

IMHO, about everything they have as far as amps has been copied from
other manufacturers (IE: Heathkit, etc). This, including the mistakes
of before. Tom also evidently claims to have worked for Heathkit, or
was close with the designers. I really think that is a bunch of hoopla
myself. He may have spoken to a few, but I don't think he ever worked
for them. When Rich asked him about his association on Amps, he
declined to answer.

later.... Jim VE7RF

Best,

Will

ORIGINAL MESSAGE:

On Thu, 21 Sep 2006 23:41:38 +0200, "Peter Voelpel"
<df3kv@...> wrote:

I would answer if the message was not html, where I can?t quote parts but
have to resend the whole bunch.
I will not allow html on my mailer.
I don?t want to go to the yahoogroup website everytime just for answering
messages.
But I go there periodically and answer then

------------ REPLY FOLLOWS ------------

Slightly OT, but if you use Forte's Agent program you can switch
between HTML display and plain text by pressing the "/" key. Neato.

Bill, W6WRT

Just in case some of you don't already know

On Sep 21, 2006, at 2:50 PM, Don Nesbitt wrote:

Ok - you all have worn me out. I'll unsubscribe.
Maybe there is a group that really is interested in
amplifiers. 73 -- Don N4HH

The AMPS reflector might be to your liking, Don. cheerz

--- R L Measures <r@...> wrote:

On Sep 21, 2006, at 11:31 AM, pentalab wrote:

--- In ham_amplifiers@..., "RICHARD

GEORGE" <k6kwq@...>

wrote:

It's also funny that when I asked on the amps

reflector if Rich

had been kicked off, Tom wrote back to me the

reasons he was kicked

off for, before it ever showed up on the

reflector that he was gone.

The admin guy didn't answer me until the next

day. If the admin guy

is not Tom, then he must be helping the admin guy

censor.

### Now this just cracks me up !! Were the

reasons that

Tom gave you.. identical to the "official" ones

on the now

defunct ..'amps' ????

### I also noticed that once the dust

settled... that W8JI is

back at it again...... posting left, right and

center...

on 'amps' !!

### some poor fellow wants to build a hb tube

amp.

Tom.. 'suggests' he build a 12 vdc SS device.

chortle

### If Tom Rauch is not the admin/censor of

'amps'..... then

he's certainly joined at the hip of whoever

is... or has a huge

influence over the ...."mystery censor" .

### Rich tells me... that the mega mailing

list is now defunct

on 'amps'.

Early on, AMPS provided a list of members' e-mail
addresses, but when
the moderator/censor found out that this is how I
was going around
his censoring of my posts, the members list
vanished. Thus, when my
posts were recently being censored, I resorted to
hand compilation to
assemble the AMPS Bypass List.

To me... that's the straw that broke the

camels

back.

The last straw was Tom censoring my post explaining
why the Tx to Rx
bias speed is blazingly fast in the TL-922.

### IMO... 'amps' has just degenerated into a

... "Tom Rauch

knows everything soapbox/platform"

Which is precisely what W4AN (SK) and W8JI intended
it to be back in
late 1996.

RE: Tom knows everything: A friend met a stranger
at Dayton and
struck up a mostly one-sided conversation. The
impression my friend
got was that the stranger acted like he knew
virtually everything
worth knowing about amateur-radio. Later he found
out who he had
been talking to. Any guesses?

## In the past..... anybody who didn't have a

callsign got

booted from 'amps'...... ditto with some very

knowledeable

11m amp builders...... and also Carl, KM1H....

who was a wealth

of practical info.

Carl's mistake was in dissin' the "expert". cheers,
Jim

### who ever designed the undersized tank

coils in the AL-80B

was a complete idiot imo. The wire ga is

the same size as

what's used in a 200 w Drake T4XC TX.

later.... Jim VE7RF






Yahoo! Groups Links

R L MEASURES, AG6K. 805-386-3734
r@...

__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around




Yahoo! Groups Links

R L MEASURES, AG6K. 805-386-3734
r@...

On Sep 21, 2006, at 2:17 PM, badgerscreek wrote:

--- In ham_amplifiers@..., "coffmado" <coffmado@...> wrote:

Gese, hasn't the censor thing run its course. When do we start
discussing amplifiers?

Doug

I think its unfortunate how most ham radiogroups have evolved in to
some kind of cult worship society or worst product worship society.

As I see it, guru worship with a large pack of yippy lap-dogs takes the cake.

It seems some forget what the purpose and aims all these groups are
for, that is that they here to foster the spread of knowledge.

To me, passing along what we OTs have learned is worthwhile -- despite the hairpulls with censors and "experts"..

What we have on many ham newsgroups, are some very well meaning
characters who go beyonds the stated aims of groups.

Well meaning people are not into being worshiped.

The most annoying thing about ham groups is the request for a
callsign. Now since when do you need a callsign to use the internet?,
or when you need to show your drivers license to join a car
discussion group? This form of moderation is under the guise of
wanting to control spam, which is nonsense.

Indeed. After Bill was gone, Tom ran amuck.

To me the content of the
post to newsgroup should determine its value. Why many want callsigns
is so that they can indentify the person posting for personal attacks
in most cases.

If technical editing is required why not let the members of the group
select a few technical moderators, if 10 agree the post is garbage
then it can get deleted.

If a post contains technical garbage, better to let the members who know better critique its author.

... ... ...


R L MEASURES, AG6K. 805-386-3734
r@...

Ok - you all have worn me out. I'll unsubscribe.
Maybe there is a group that really is interested in
amplifiers. 73 -- Don N4HH

--- R L Measures <r@...> wrote:

On Sep 21, 2006, at 11:31 AM, pentalab wrote:

--- In ham_amplifiers@..., "RICHARD

GEORGE" <k6kwq@...>

wrote:

It's also funny that when I asked on the amps

reflector if Rich

had been kicked off, Tom wrote back to me the

reasons he was kicked

off for, before it ever showed up on the

reflector that he was gone.

The admin guy didn't answer me until the next

day. If the admin guy

is not Tom, then he must be helping the admin guy

censor.

### Now this just cracks me up !! Were the

reasons that

Tom gave you.. identical to the "official" ones

on the now

defunct ..'amps' ????

### I also noticed that once the dust

settled... that W8JI is

back at it again...... posting left, right and

center...

on 'amps' !!

### some poor fellow wants to build a hb tube

amp.

Tom.. 'suggests' he build a 12 vdc SS device.

chortle

### If Tom Rauch is not the admin/censor of

'amps'..... then

he's certainly joined at the hip of whoever

is... or has a huge

influence over the ...."mystery censor" .

### Rich tells me... that the mega mailing

list is now defunct

on 'amps'.

Early on, AMPS provided a list of members' e-mail
addresses, but when
the moderator/censor found out that this is how I
was going around
his censoring of my posts, the members list
vanished. Thus, when my
posts were recently being censored, I resorted to
hand compilation to
assemble the AMPS Bypass List.

To me... that's the straw that broke the

camels

back.

The last straw was Tom censoring my post explaining
why the Tx to Rx
bias speed is blazingly fast in the TL-922.

### IMO... 'amps' has just degenerated into a

... "Tom Rauch

knows everything soapbox/platform"

Which is precisely what W4AN (SK) and W8JI intended
it to be back in
late 1996.

RE: Tom knows everything: A friend met a stranger
at Dayton and
struck up a mostly one-sided conversation. The
impression my friend
got was that the stranger acted like he knew
virtually everything
worth knowing about amateur-radio. Later he found
out who he had
been talking to. Any guesses?

## In the past..... anybody who didn't have a

callsign got

booted from 'amps'...... ditto with some very

knowledeable

11m amp builders...... and also Carl, KM1H....

who was a wealth

of practical info.

Carl's mistake was in dissin' the "expert". cheers,
Jim

### who ever designed the undersized tank

coils in the AL-80B

was a complete idiot imo. The wire ga is

the same size as

what's used in a 200 w Drake T4XC TX.

later.... Jim VE7RF






Yahoo! Groups Links

R L MEASURES, AG6K. 805-386-3734
r@...

__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around

开云体育

On Sep 21, 2006, at 12:57 PM, coffmado wrote:

Gese, hasn't the censor thing run its course. When do we start
discussing amplifiers?

Censoring anyone who questioned Tom's dicta was part of AMPS for a bit over 9-years, so some discussion about what we endured is in order, Doug. cheerz.

Doug







Yahoo! Groups Links

R L MEASURES, AG6K. 805-386-3734
r@...

I have obtained a Drake L7 amp from an estate. It had lightning
damage to the power supply. I need to replace a couple capacitors and
diodes. Has anyone rebuilt this supply? I read somewhere on the Net
that a complete board can be purchased from a company in California
but I lost the info. Any suggestions?

Tom W8JWN

On Sep 21, 2006, at 11:31 AM, pentalab wrote:

--- In ham_amplifiers@..., "RICHARD GEORGE" <k6kwq@...>
wrote:

It's also funny that when I asked on the amps reflector if Rich
had been kicked off, Tom wrote back to me the reasons he was kicked
off for, before it ever showed up on the reflector that he was gone.
The admin guy didn't answer me until the next day. If the admin guy
is not Tom, then he must be helping the admin guy censor.

### Now this just cracks me up !! Were the reasons that
Tom gave you.. identical to the "official" ones on the now
defunct ..'amps' ????

### I also noticed that once the dust settled... that W8JI is
back at it again...... posting left, right and center...
on 'amps' !!

### some poor fellow wants to build a hb tube amp.
Tom.. 'suggests' he build a 12 vdc SS device.

chortle

### If Tom Rauch is not the admin/censor of 'amps'..... then
he's certainly joined at the hip of whoever is... or has a huge
influence over the ...."mystery censor" .

### Rich tells me... that the mega mailing list is now defunct
on 'amps'.

Early on, AMPS provided a list of members' e-mail addresses, but when the moderator/censor found out that this is how I was going around his censoring of my posts, the members list vanished. Thus, when my posts were recently being censored, I resorted to hand compilation to assemble the AMPS Bypass List.

To me... that's the straw that broke the camels
back.

The last straw was Tom censoring my post explaining why the Tx to Rx bias speed is blazingly fast in the TL-922.

### IMO... 'amps' has just degenerated into a ... "Tom Rauch
knows everything soapbox/platform"

Which is precisely what W4AN (SK) and W8JI intended it to be back in late 1996.

RE: Tom knows everything: A friend met a stranger at Dayton and struck up a mostly one-sided conversation. The impression my friend got was that the stranger acted like he knew virtually everything worth knowing about amateur-radio. Later he found out who he had been talking to. Any guesses?

## In the past..... anybody who didn't have a callsign got
booted from 'amps'...... ditto with some very knowledeable
11m amp builders...... and also Carl, KM1H.... who was a wealth
of practical info.

Carl's mistake was in dissin' the "expert". cheers, Jim

### who ever designed the undersized tank coils in the AL-80B
was a complete idiot imo. The wire ga is the same size as
what's used in a 200 w Drake T4XC TX.

later.... Jim VE7RF






Yahoo! Groups Links

R L MEASURES, AG6K. 805-386-3734
r@...

--- In ham_amplifiers@..., Dino Darling <dino@...> wrote:

I have plans to build my first amplifier using a 4CX250B. I have

the> tube, socket, enclosure, and some parts. Maybe we can build it
right> here on the reflector! I'm looking forward to the education!

Dino - K6RIX
dino@...

### After 15 x hb linears..imo.. why even mess with a 4 x
4CX250B linear ???

### 4 x sockets... 4 x chimney's.... 4 x tubes 4 x parasitic
suppressor's..... regulated rx/tx bias supply...... reg
screen supply etc.

### You don't put 4 x engines under the hood of a car. IMO...
if one tube doesn't do the job... select a bigger tube.


### These YC-156's [and YC-172's] are a huge bang for the
buck. 200 w drive = 10kw + out. No socket required. $400.00

### after messing about with multiple tube linears in the
past... and also trying to balance the airflow through all of
em... and also trying to adjust individual idle currents, and
also trying to balance the drive levels into each tube.... I
swore I'd never build anything but single tube linears ever
again.......... best thing I ever did.

### trbl shooting a 4 x tube amp at times is no fun either.

### If u attempt a 4 x tube linear.... make sure you have at
LEAST 4-6 new tubes, or known good ones.

### My conclusion after doing this since 1974 is it's just as
easy to build a big amp... as a small one.

Later.... Jim VE7RF