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Re: Svetlana's website ???

pentalab
 

--- In ham_amplifiers@..., "Mike\(W5UC\) &
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









_____
Re: Passed 100 total members

 

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

On Sep 29, 2006, at 6:27 AM, kr4da wrote:

Passed the 100 total members mark this week.

de KR4DA Bob







Yahoo! Groups Links
Passed 100 total members

kr4da
 

Passed the 100 total members mark this week.

de KR4DA Bob
HA-10 Conversion

Mike&#92;(W5UC&#92;) & Kathy&#92;(K5MWH&#92;)
 

¿ªÔÆÌåÓý

Good Evening All:

?

I am looking for information about converting the HA-10 Warrior for 160 meters.? 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?

?

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

?

?

?
Re: Water Cooling A GS-35

 

Silicone rubber is used to insulate HV wiring.

On Sep 28, 2006, at 4:11 PM, jmltinc@... wrote:

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

-John, N9RF



Yahoo! Groups Links
Bird 5000H element resistor value?

 

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
Re: Water Cooling A GS-35

 

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

-John, N9RF
Re: Calculating Grid dissipation revisted

pentalab
 

--- 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
Re: Calculating Grid dissipation revisted

Tony King - 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
Re: Calculating Grid dissipation revisted

pentalab
 

--- 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
4CX250

FRANCIS CARCIA
 

We have an EMI amplifier (IFI406)?with 24 4cx250s in a TWA. one of them has a short between G1 and cathode. It comes and goes with heat and when it happens the plate supply shuts down. Anybody have an idea of a safe hipot test voltage. It is not a hard short so need a way to isolate it. Only want to remove the tubes once. This thing is 1 KW out 10 KHz to 220 MHz and idles at about 7 KW resting.??
Re: Calculating Grid dissipation revisted

Bill Turner
 

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
Re: toroid tank coil

 

--- In ham_amplifiers@..., PA3DUV <pa3duv@...> wrote:

What kind of (stranded) wire (or strap) can be used best to wind a 40-
80-160 meter tankcoil on a large toroid? Rated output is approx. 6 kW


Cheers, Dick
PA3DUV
Hi Dick,

One idea is to use two or three number 10 or 12 gauge enamel side by
side wound as a ribbon, connected in parallel. They can be pre-formed
by wrapping with glass tape first. Since you'd be using a powdered iron
core, they need lots insulation.

73, Roy K6XK
Re: Transformers on Wiki again...

Frank Goenninger
 

Am 27.09.2006 um 03:25 schrieb craxd:
All,

I hate to say that some dumb a$$ deleted almost everything I had
written except some corrections about the windings. I'd about bet they
were the one who wrote the screwed up stuff I had to correct. The guy
who edited it wrote he thought only 5-6 people might find it helpful.
Now, the page is about worthless but just to describe what a
transformer is. All the useful formulae are now gone. It's a shame I
didn't save it all as there was about 16 hours work in that.
Nothing really lost. Using the "history" tab on the page shows who did what with it. You could paste your version again in there... Your text is still available. It might help to create a Wikipedia account and do the mods under this account.

What happened to you is why I personally prefer to put stuff on a static page and let google do the rest of it (making it known to the public).
I did
leave the a$$hole a scaving responce and asked a question wanting to
know if they want people to learn or not. I think most in the
discussion are audiophiles who don't know one end from the other.
I will leave the guy a message, too. I might even decide to put your stuff back again in myself ;-)

73 Frank DG1SBG
toroid tank coil

PA3DUV
 

¿ªÔÆÌåÓý

What?kind of (stranded) wire (or strap) can be used best to wind a 40-80-160 meter tankcoil on a large toroid? Rated output is approx. 6 kW
?
?
Cheers, Dick
PA3DUV
Re: 4 Tube 811 Amplifier.

la3pna
 

I have done some modifications to the shematic, so i have uploaded an
revided shematic.

I can't see the reason for floating the B-, to mesure the current i
would just add an 0.1 ohm resistor between the PSU's - tab and ground.
It sould be easy to mesure the current over that? or is it somting I
have missed?

I also have to order an transformer, since there are just 2 producers
of small transformers, i would have to order an 600V and use an
voltage doubler. I could get an 700VA transformer realy cheap, but is
it enoug? I've read that SSB only has an dutty of about 20%.

73 de Thomas.

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

Hello Thomas,

A couple of suggestions for your amplifier...

First, I would float the B- to make metering of plate and grid current
readily available to you. It takes no more than two resistors and a few
diodes to protect the metering to make this big improvement.

Second, I would suggest that you do not do T/R keying of the bias the
way that is shown on your schematic. That method is similar to the
Clipperton L and a few others. The flaw is that during the
transition of
the contacts the cathode will rise to near full anode potential and
when
you make contact with your bias circuit, you are hitting it with a very
high voltage at that moment. A simple cure for it without changing the
circuit entirely, and this applies to the Clipperton L as well, is to
place a jumper across the wiper and the normally closed contact of the
keying relay. That will keep the cutoff resistor in the circuit all the
time and prevent the cathode voltage from soaring. I would also place a
fuse in series with your bias circuit rated at just over your maximum
expected plate current. Also, a Metal Oxide Varistor or an NE-2 neon
bulb in parallel with the bias circuit will help protect it against
transient voltages. You may want to increase the value of the cutoff
resistor to about 20K to minimize the current in standby.

73, Tony W4ZT
Re: Calculating Grid dissipation revisted

FRANCIS CARCIA
 

The best way to measure a transformer gut temp is measure the winding resistance cold then hot and determine the real temperature rise by the copper constant. I think it is about .4%/degreeC. wa1gfz

R L Measures wrote:


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

> --- In ham_amplifiers@yahoogroups.com, R L Measures 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.
>
>
>
>>> ### Average plate current on SSB is about 1/2 that of the
>>> dead cxr condition.
>>
>> ... closer to 1/3
>
> ### see above.
>
>>
>>> Average power output [not pep] is only
>>> aprx 1/5 th the pep output of the amp.
>>>
>>> ### Next step is... we will try and meausre the heat on the
>>> outer core with a Fluke 62 mini IR thermometer. Of
>>> course... the heat deep inside the core will always be way
>>> more.
>>
>> Resin potting helps dissipate heat from deep in the core.
>>
>>> I have loads of air blown across it anyway.... and
>>> reg is not too bad.
>>>
>>> ### I'm convinced 2 ga wire from main panel to HV supply
> [and internal wiring] is not big enough !
>>
>> RICH SEZ .. The Plywood Box amplifier was 100' from the breaker
> box. It did 14k out pep and the wire was #4 Cu.
>
> ### #4 is too puny...esp 100' away. Heck that amounts to a
> 200' loop !! 4 ga CU won't handle 400+ A on peaks...
> without a big v drop.... esp with 200' of loop resistance....
> never mind ur small ga aluminium drop wires coming into the
> house.. on top of that.
>
> #### The next question is/was gonna be.... how was ur HV
> regulation... with a dead cxr ???? [static] and also on ssb
> [dynamic] ??? You can't even run a dead cxr.... with just
> your 40 A breaker. You need a bare minimum of a 100 A
> breaker.
>>
>>>
>>>
>>> ### What's a fairly precise way to measure peak AC current
>>> [under load] from the 200 A main panel ????
>>
>> A 1-milliohm resistor in series with a calibrated oscilloscope to
>> measure the V-drop across it. The Plywood Box drew so much peak
>> current that the 240v wires could be heard vibrating in the attic
>> when I used a 30pps pulser to tune the sucker up. Also, at night,
>> the neighbor's porch-light blinked.
>
> #### A 1 milliohm resistor... inserted in one leg of the 240 v
> line that will handle 400 + A is gonna be a trick.

It's just a matter of execution.

> Since we
> know the exact length of the cable.... and it's exact dc
> resistance... perhaps measuring the V drop end to end will
> work?? ....

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

> or perhaps measuring the peak v across the 240v
> line.... using the peak max/min function on a fluke 87 [1 msec
> snap shots] .... or my scope might work... and trigger off
> the 'lows' in the acv ??
>
> ### 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.

> 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.

> Later..... Jim VE7RF
>
>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
>
>
>

R L MEASURES, AG6K. 805-386-3734
r@...
Re: Transformers on Wiki again...

craxd
 

All,

I hate to say that some dumb a$$ deleted almost everything I had
written except some corrections about the windings. I'd about bet they
were the one who wrote the screwed up stuff I had to correct. The guy
who edited it wrote he thought only 5-6 people might find it helpful.
Now, the page is about worthless but just to describe what a
transformer is. All the useful formulae are now gone. It's a shame I
didn't save it all as there was about 16 hours work in that. I did
leave the a$$hole a scaving responce and asked a question wanting to
know if they want people to learn or not. I think most in the
discussion are audiophiles who don't know one end from the other.

Best,

Will

--- In ham_amplifiers@..., "craxd" <craxd1@...> wrote:

All,

I finally did finish all I was going to do on Wikipedia about power
transformers. I found I also had to edit a few stubs and others. The
definition of Oersted was completely screwed and they had it tagged
for a re-write which I did the complete thing, and it's now correct.
I
had to correct the one on Gilberts too. They're still may be more,
and
if any of you were to catch these, please let me know.

I hope any who use this will find it helpful as it now has the most
info on the web about them. I do still hope a few here might add to
the RF transformer parts. Anyone can edit these by the way, and you
don't have to join anything.

Thanks,

Will
Re: Calculating Grid dissipation revisted

 

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.



### Average plate current on SSB is about 1/2 that of the
dead cxr condition.
... closer to 1/3
### see above.


Average power output [not pep] is only
aprx 1/5 th the pep output of the amp.

### Next step is... we will try and meausre the heat on the
outer core with a Fluke 62 mini IR thermometer. Of
course... the heat deep inside the core will always be way
more.
Resin potting helps dissipate heat from deep in the core.

I have loads of air blown across it anyway.... and
reg is not too bad.

### I'm convinced 2 ga wire from main panel to HV supply
[and internal wiring] is not big enough !

RICH SEZ .. The Plywood Box amplifier was 100' from the breaker
box. It did 14k out pep and the wire was #4 Cu.

### #4 is too puny...esp 100' away. Heck that amounts to a
200' loop !! 4 ga CU won't handle 400+ A on peaks...
without a big v drop.... esp with 200' of loop resistance....
never mind ur small ga aluminium drop wires coming into the
house.. on top of that.

#### The next question is/was gonna be.... how was ur HV
regulation... with a dead cxr ???? [static] and also on ssb
[dynamic] ??? You can't even run a dead cxr.... with just
your 40 A breaker. You need a bare minimum of a 100 A
breaker.



### What's a fairly precise way to measure peak AC current
[under load] from the 200 A main panel ????
A 1-milliohm resistor in series with a calibrated oscilloscope to
measure the V-drop across it. The Plywood Box drew so much peak
current that the 240v wires could be heard vibrating in the attic
when I used a 30pps pulser to tune the sucker up. Also, at night,
the neighbor's porch-light blinked.
#### A 1 milliohm resistor... inserted in one leg of the 240 v
line that will handle 400 + A is gonna be a trick.
It's just a matter of execution.

Since we
know the exact length of the cable.... and it's exact dc
resistance... perhaps measuring the V drop end to end will
work?? ....
That would work. With a C-filter, for every ampere indicated, expect 10 amperes peak.

or perhaps measuring the peak v across the 240v
line.... using the peak max/min function on a fluke 87 [1 msec
snap shots] .... or my scope might work... and trigger off
the 'lows' in the acv ??

### 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.

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.

Later..... Jim VE7RF







Yahoo! Groups Links










R L MEASURES, AG6K. 805-386-3734
r@...
Transformers on Wiki again...

craxd
 

All,

I finally did finish all I was going to do on Wikipedia about power
transformers. I found I also had to edit a few stubs and others. The
definition of Oersted was completely screwed and they had it tagged
for a re-write which I did the complete thing, and it's now correct. I
had to correct the one on Gilberts too. They're still may be more, and
if any of you were to catch these, please let me know.

I hope any who use this will find it helpful as it now has the most
info on the web about them. I do still hope a few here might add to
the RF transformer parts. Anyone can edit these by the way, and you
don't have to join anything.

Thanks,

Will
40881 - 40900 of 41158