Just in case anybody is interested.... RF Parts has a sale on MANY
of their tubes.... both triodes... + tetrodes.

eg- Svetlana 3CX-3000A7 $695.00
Svetlana 3CX-6000A7 $855.00 [reg $975.00] !

Of course the above tubes require the expensive socket/grid
ring combo.... another $375.00 !! ouch !

Arnold Howell of Howell tube sales, sells the infamous Eimac
YC-243 [socketless 3CX-6000A7] for around $1100.00.... which
is IMO.. the best bargain of all.... comes with a built in 1/8"
thick, silver plated grid flange.. 4.25" diam........ and two...
just huge fil lugs. [5/16" threaded, embedded studs].

Both the 3CX-6000A7 + YC-243 are the sleeper of the year !
Although rated for 6 kw anode diss [205 cfm @ .4" water..
at an inlet air temp of 50 deg C].... this stock anode rating
can EASILY be increased to almost 9 kw.... simply by blowing more
air through it, and using a lower inlet air temp, and using a 9"
square box around the tube.. with a teflon top. [310 cfm @ .9"
water at an inlet air temp of 25 deg C]. A Dayton 5C508 dual
speed blower fits this requirement perfectly.




The YC-156 medical MRI pulls... can still be had from Norman
Hockler..[N8NH]... who also has the mating fil xfmr's.. SK-306
chimney's, etc. Norm also has new globars... 90 watt CCS...
glass bodied SP type... 3/4 " diam x 5" long.. 50 ohm. We use
these for parasitic suppressors... just wind em with 3 turns
of 3/4" wide strap... and install em in standard 3/4" silver
plated fuse holders...with end retainers. The SP globars
are good for 350 deg C... CCS ! ZERO fireworks, ultimate
parasitic suppressor....Rock stable.

Norm sells the YC-156's for aprx $375.00 - $450.00. These are
a 3CPX-15,000B7... with a 5 kw ..4.94" OD cooler.... built in
grid flange... no socket required.... and almost 19db of gain !

You fellow's who want a "project" this fall/winter.... well here
you go !

Later.... Jim VE7RF

The actual link is: <>

73, Tony W4ZT

Frank Goenninger wrote:

Hi Mike and all:

Am 29.09.2006 um 20:04 schrieb Mike(W5UC) & Kathy(K5MWH):

There is a site called The Wayback Machine, and references to old
or outdated URL’s are stored there. It can be found at:
www.archive.org/web/web.php

Wow ! Thanks for the pointer!

I went to where I got the inactive Svetlana URL(above) and plugged
it in to The Wayback Machine and it found several stored references
to the page. I printed the article from the internet page. I then
tried to copy & paste it into Word, but it came out all funky. If
you have trouble let me know and I will scan it and send it to you.
I think the original article appeared in CQ, but I don't know the
date. Good Luck.

Using the Mac OS X built-in PDF creator I made a PDF and uploaded it
to the files section of this group (Hey I love my Mac!). If someone
needs another one from another page/ document please let me know. I
also have Adobe Acrobat Professional so copying text passages or
images from within a PDF is possible for me, too. Just drop an email
and I'll see what I can do.

73, Frank DG1SBG

开云体育

Duh!

-John, N9RF

Am 29.09.2006 um 19:09 schrieb Tony King - W4ZT:

pentalab wrote:
<snip>

### I can't get into Svetlana's site either.....

I had this same problem... it insisted that since I was in the USA there
was nothing there for me. That was using my favorite browser, Firefox.

I opened the dreaded Internet Explorer, which I NEVER use, and it went
there just fine. Do NOT click on USA as your location. Select rest of
the world.

73, Tony W4ZT

??? How did achieve that? For me the query for the host www.svetlana.com itself does not work (using low level tools like nslookup [name service lookup] yields a "server unknown" message with a SERVFAIL (meaning the query did fail - not "there's no entry for www.svetlana.com). Strange, that!

Tony, could you post a link other than the bare www.svetlana.com that works for you? Thanks!!

73 Frank DG1SBG

--- In ham_amplifiers@..., "kr4da" <kr4da@...> wrote:

Passed the 100 total members mark this week.

de KR4DA Bob

### Now at 104 member's..... I'd say vehemently.... that
Rich, and anybody else who has ever either.. been booted
off 'amps'.... or had their posts trashed... or edited.....or
deleted.... has finally been vindicated !!

### This group has THE distinct advantage...... throwing in
stuff like jpegs, pix, schematics.. polls, and files, is just
gravy.

### My prediction was, [and still is] this group would grow
in leaps and bounds..... and leave 'amps'... in the dust.

## IF W8JI, et all... ever show up here.... it will
be..."poetic justice".

Later..... Jim VE7RF

pentalab wrote:
<snip>

### I can't get into Svetlana's site either..... have not been able to.... for a couple of yrs at least. I printed out some of their stuff but not what u need. What's the deal ? Svetlana's site was superb.... showing u insides of tubes, etc. Jim VE7RF

Does anyone have this conversion info or can someone out of the US

retrieve

the info and forward it to me.

Many Thanks
73,

Mike, W5UC

I had this same problem... it insisted that since I was in the USA there was nothing there for me. That was using my favorite browser, Firefox.

I opened the dreaded Internet Explorer, which I NEVER use, and it went there just fine. Do NOT click on USA as your location. Select rest of the world.

73, Tony W4ZT

--- In ham_amplifiers@..., "Mike&#92;(W5UC&#92;) &
Kathy&#92;(K5MWH&#92;)" <w5uc@...> wrote:

Good Evening All:


There is a Svetlana page with the info on it but I am told that we
in the US are presently unable to access that site at

### I can't get into Svetlana's site either..... have not been
able to.... for a couple of yrs at least. I printed out some of
their stuff but not what u need. What's the deal ?
Svetlana's site was superb.... showing u insides of tubes, etc.

Jim VE7RF

Does anyone have this conversion info or can someone out of the US

retrieve

the info and forward it to me.



Many Thanks



73,

Mike, W5UC









_____

Bob -- It would be interesting to compare this with the AMPS total, but that information has been kept secret ever since someone who got booted off of AMPS by the moderator/censor, downloaded the members e- mail addresses, bypassed the moderator/censor, and started posting direct to members.
I think it is pretty safe to say that censorship will never be very popular in America.

cheerz

Passed the 100 total members mark this week.

de KR4DA Bob

开云体育

Silicone rubber is used to insulate HV wiring.

I'm repairing a Bird 5000H element (2-30 MHz 5 KW) and the resistor in
the slug appears to be wrong. What is the nominal resistor value for
this element?

TIA

Does this mean there is no problem with routing the silicone cooling lines
out of the HV end of the line?

-John, N9RF

--- In ham_amplifiers@..., Tony King - W4ZT <w4zt-
060920@...> wrote:

pentalab wrote:
<snip>

### You would have to at least double the size of the caps

in a doubler. A doubler's caps only gets charged 60 x per

second....... a FWB's caps get charged 120 x per second.

<snip>
true, but in the FWD, each half of the stack is charged on

opposite half cycles so half the stack is always being charged.

### A FWDoubler is nothing more than two 1/2 wave rectifiers...
in series !


### True.. BUT.... the load is across both series stacks of caps !
The theory is... since each stack only gets charged up 60 x per
second..... [instead of 120 x per second ..like a FWB]... the caps
in a doubler have to hold their charge TWICE as long.... hence
they gotta be TWICE as big to start with !

### There is no free lunch. The advantage of a doubler is you
only need 1/2 the voltage on the xfmr sec..... and that's where
it ends. You should be able to make the wire bigger on a xfmr
with only 1/2 the V.... which should be capable of pumping out way
more current.......which it will have to........ in order to
charge up caps that have a capacitance value that is double
that of the FWB.... the saving grace is... u only have to charge
one stack ..at a time.

### If Rich wanted a 9900 V HV supply....... he shoulda used
a 7200 V pole pig..[come in 10-15-25 kva... with or without the
oil]... in a FWB.

### The doublers in my 3 x L4B's work not too bad... reg is
pretty good..... ripple is 3%.... u can see the ripple on any RF
scope.. with max dead cxr. [25 uf total]. Back then... u couldn't
get bigger lytics...... now u can.

73... Jim VE7RF

73, Tony W4ZT

pentalab wrote:
<snip>

### You would have to at least double the size of the caps in a doubler. A doubler's caps only gets charged 60 x per second....... a FWB's caps get charged 120 x per second.

<snip>
true, but in the FWD, each half of the stack is charged on opposite half cycles so half the stack is always being charged.

73, Tony W4ZT

--- In ham_amplifiers@..., R L Measures <r@...> wrote:

On Sep 26, 2006, at 5:02 PM, pentalab wrote:

--- In ham_amplifiers@..., R L Measures <r@...>

wrote:

RICH SEZ.. SSB has a duty cycle of less than 20%, so it's quite

different than RTTY.

### Dream On.... unless you chopped all the audio off below
350 hz..... or the plate current meter ballistics are out to
lunch.

During an ahhhhhhhh, I see about 1/3 of A0 anode current. If one
transmits half the time, that's a duty-cycle of 1/6.

#### I'd call that 1/3.... NOT 1/6th. What if I give a 5 min
disertation? or some contester calss 'cq' for 3 mins
straight?

### The big kicker is gonna be CW. Dashes are gonna be at
least 3 x as long as dots. I set my dashes so they are 3.6
x longer than dots.... send cw at 10-16 wpm.... and u are in
for a big surprise....... duty cycle is WAY UP.


RICH SEZ Resin potting helps dissipate heat from deep in the core.

### agreed.


RICH SEZ ....That would work. With a C-filter, for every ampere
indicated, expect 10 amperes peak.

### SAY WHAT ?? I used Duncan's pwr supply modeller.... and
even though the dc resistance of the primary is only .08 ohm.....
Z on primary... using their software is more like 68-70 ohms....
and peak current on the 240 v side is aprx 3.75 X steady
state readings.

### ANYTHING between 3-10 X just means EVERYTHING from
contactor's to wire, buss bar, breakers, etc... between main
200 A panel.... and up to and including the connections to the
Dahl plate xfmr primary has to be way over sized.... to
minimize V drops !!

### We took those surplus 135 A rated 3 x pole contactor's..
and simply paralled em with 1" x1" aluminum angle stock....
to make em into one big 400 A SPST-DM contactor assy. Then
stick one such assy in each leg of the 240 line..... and the 3rd
one does the step start. ....works good too. So does
slopping on 'cool amp' silver plating compound on tall the
contacts... dc resistance drops to zero every time.

### A fwb gives better reg than a doubler... for the same size

caps.

Sure, but with the required size caps for a FWD, the % regulation

is pretty much the same.

### You would have to at least double the size of the caps in a
doubler. A doubler's caps only gets charged 60 x per
second....... a FWB's caps get charged 120 x per second.

That 50 ohm glitch R we have in the B+ doesn't help
matter's any.... I lose 150 vdc right there.

... which is not noticeable at the Rx end. Originally, the

Plywood Box amplifier stupidly had a 25w glitch resistor -- most
definitely a blunderous mistake.

### agreed... BUT 150 v is a 150v... which sucks. You don't
want any less than 50 ohms either........ but any more than 50
ohms means more v drop... and more heat.

### We used 2 x paralled 100 ohm-225 watt wire wounds in the
latest project...... works good. Even with some initial HV
faults during testing [which took out one or both BUSS 3 A
sandfilled HV fuses]... the resistors didn't flinch. I was
expecting the huge instantaneous magnetic field from the
resulting 160 A to be strong enough.. to destroy em.

### 4 x 200 ohm 275 watt globars in parallel [older 60's CX
type] also work superb in glitch service.

Later.........Jim VE7RF

ORIGINAL MESSAGE:

On Wed, 27 Sep 2006 00:02:51 -0000, "pentalab" <jim.thomson@...>
wrote:

RICH SEZ.. SSB has a duty cycle of less than 20%, so it's quite

different than RTTY.

### Dream On.... unless you chopped all the audio off below
350 hz..... or the plate current meter ballistics are out to
lunch.

### Average plate current on SSB is about 1/2 that of the
dead cxr condition.

... closer to 1/3

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

It really depends on one's manner of speaking and one's individual
voice. Some people put relatively large pauses between words and
othersrunthingsalltogetherwithnopausesatall.

Bill, W6WRT
a pauser