Mike,

The kicker is, this un-named moderator said "You have been given a
wide degree of latitude - wider than many others". For what, offering
technical advice to any who asked for it? They also said "You hang out
here without any amateur call and no professional credentials other
than as an admitted former designer and builder of amplifiers for CB
service". Yup, I sure did build um, and did learn a heck of a lot
while doing it. What is his credentials, call, or name for that
matter? If you remember, Tom asked me what my credentials was, and
where I went to school too. Don't it sound fishy that he would ask the
same right after? Then went on to say, "It is no appropriate for you
to get your back up when you are asked for credentials after
questioning not one but several of the academic standards of tube
design and operation". What academic standard did I ever question? I
quoted authors like Terman. The only one I ever questioned was Tom,
and showed what he was saying was pure hogwash by quoting published
authors! Then he has the balls to say, "If you are going to question
those academic works, you need to be willing disclose your credentials
(if your PhD in Physics or Electrical Engineering?), allow them to be
examined and provide a list of your peer (academically) reviewed
research work (CV) in the field for examination.". One doesn't need a
PhD, a Ms, or Bs if they have a knowledge of the theory. Does this
mean that to be an amateur operator, one needs to have these degrees?
I actually have a degree through Ky. State Vo-Tech, but wasn't going
to tell him this. Nor, do you have to publish any papers to be
correct. Matter of fact, they've been several PhD's proven dead wrong!
Then, he goes on to say things about Rich that was to me plain liable
and slanderous (I'll bet they would bee in court), and I wont show
them here. This all over Tom trying to argue that a control grid could
become positive. It may be less negative than the cathode, or one
might say it's more positive than the cathode, but it sure can't be
positive with respect to ground or 0 Vdc! I bet I had 30 e-mails come
back to catch Tom saying this. He would argue until his last breath it
was positive. All because of something he read, and because he doesn't
understand theory enough to know better.

What put the icing on the cake for me was when Tom commented on a post
I made about determining the rms current a transformer needs to supply
to a FWB cap input supply. Tom replied I was wrong, and that it was
garbage (No wonder why some Ameritrons are poorly designed). When I
sent back a reply, with a link to Hammond Transformer website with the
same formula, the un-named modeartor wouldn't post it (censored it).
In other words, he was hanging me out to dry to look like a fool over
not letting Tom be wrong. Well, that was it, I started by-passing him
with direct e-mails to the members that I had in my address book. The
rest was, well history. ; )

Best,

Will


--- In ham_amplifiers@..., "Mike Sawyer" <w3slk@...>
wrote:

Will, et al,
I challenged the 'administrator' about what calls for being

banned from the list. Included were email lists and having a 'lack' of
a call sign. Neither one, I pointed out were part of the list's own
rules/regs. But that was another day. I'm about ready to "vote with my
feet." My only regret is that it isolates some very good technical
knowledge that hasn't found its way over here (yet).

Mod-U-Lator,
Mike(y)
W3SLK

----- Original Message -----
From: craxd
To: ham_amplifiers@...
Sent: Tuesday, October 03, 2006 8:06 PM
Subject: [ham_amplifiers] Re: Hi-


I know of several that tried and the post never made it. Two did,

but

the rest went bye bye. The unnamed, "no-callsign either" moderator,
who was on me about showing a callsign, has his eye on every post

that

comes into Amps mainly to protect one person for any, well lets say,
embarrasing moments.

When a groups moderator censors others posts who contradict one that
is plainly wrong, allowing the wrong comment to show, and not the
correct one, it's not a place to be. Correct being that the one
posting it actually knows what they are talking about! : ) It's even
worse when the moderator lets the one in question take pot shots at
others, and when they reply, the post gets canned before the others
can see it.

Now, I admit, I was one of the ones that was guilty of e-mailing
everyone in my address book and bypassing the moderator. The

moderator

aimed that one admonishment about harvesting e-mails at two people,
Rich and myself. However, this moderator must think that neither of

us

has an address book on our own without his so-called "harvesting"
going on. I thought I still have the right, by the 1st amendment, to
e-mail anyone I damn well wish. I'm not aware that has EVER been
changed.

Sincerely,

Will

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

On Oct 3, 2006, at 2:40 PM, zerobeat40 wrote:

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

--- In ham_amplifiers@..., "zerobeat40"

<zerobeat40@>

wrote:

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

wrote:

As I understand it, announcements of this group's existence

on

the

AMPS group were somewhat censored.

Your understanding is incorrect. There were several

announcements

of

this group, as well as the larger more-established

rfamplifiers

group

on Yahoo that made it to AMPs. Everytime someone posted on

this

group

that "my announcement did not get posted", I looked at AMPS -

and

it

was, in fact, posted.

### DREAM ON. I checked 'amps' on contesting .com 3

times

now.... with a microscope [pulling up their archives]..... it

ONLY

got posted TWICE..... once from Mike... once from Alek

later........Jim VE7RF

Yes, that is the distinct number of people who claimed to have
attempted to post it and claimed that it was not posted.

I heard from others who said they tried to post the info about the
new group and it did not not get past the censor.

Thank you for the corroborration.

Z

Yet another unidentified station.

Yahoo! Groups Links

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

A 3 phase service is mighty fine to have if one can afford to have it
put in. I've not checked on the price in a while, but back in 1985, a
200 amp 220 volt service ran around $2000 from the power company for
the transformers, and the service entrance, meter base, etc was extra.
I was having one put in at my machine shop building I had at the time.
I wish I had the health back to do all that again. At the time I had
an electric shop running, and a machine and assembly shop a couple of
miles up the road. I used to design and build custom fab machinery for
the railroads. Sure is a good business to be in. Anyhow, 3 phase can
sure make life a lot easier if you plan on running reverseable motors,
and anything else that needs some umph behind it. One could do it with
a pony motor, but I'm not sure how good that would work.

Back in the old days, and some do this now, is run a generator (really
an alternator without the rectifier stack) in a mobile supplying LV 3
phase to run a HV transformer. That get's you out of running an
inverter. A certain company down in Memphis, Tn used to supply a
mobile kW (1800 PEP out) with the generator that way. I here about a
guy in Florida building these today, and was buying the transformers
from Galaxy Transformer. I recon he's built a few with tubes with
handles. Of course you need enough engine to run it too.

Best,

Will


--- In ham_amplifiers@..., "Peter Voelpel" <df3kv@...>
wrote:

To achieve 1,5% ripple from a 6-pulse power supply of 5KV at 3A you

will

need a capacitor of 0,32?F.
Without any cap ripple will be 4%.
You will not here any hum from a transmitter without capacitor in

the

6-pulse capacitor when using sideband transmissions.
From a carrier you here little hum on zerobeat.

The formula to find C for the 3-phase bridge circuit is the same as

for any

other circuit, just calculate C from XC by using 300Hz in the

formula.

How the transformer is connected does not matter, usually the

primary will

be delta for best efficiency and the secondary will be star

connected.

You will have 2 diodes per leg. The voltage across one winding is

dc/sqrt6.

I my 7KV 4A CCS P/S I use UGE1112AY4 diodes by IXCYS, 3 per leg,

just scewed

one into the next.



The transformer secondary is 5KV +/-5%, +/-10% phase to phase, or

2887V

across one winding.
I use 2?F 10KV for smoothing and a crowbar overload circuit with it.

73
Peter


________________________________

From: ham_amplifiers@... [mailto:

ham_amplifiers@...]

On Behalf Of pentalab

Then, if we talk 3-phase supply and 6-puls rectifying,
lets say around 5 kV DC potential, how much glitch C
is needed to achieve 1.5 percent ripple?

### Dunno. You would only have 5% ripple with NO cap.... and
with a resonant choke set up.....you probably wouldn't need any
C at all ! [3 phase]

### IF no resonant choke setup... and just a straight C input
filter.... I'm guessing around 5-16 uf would be plenty. It
would also highly depend on the load.

### I haven't found any formulae for a C input filter HV
supply........ with 3 phase. I don't have access to 3 phase....
so never pursued it. It would be the ultimate setup. IF you
find anything... let me know... as I'm most interested. Somebody
is going to ask me to engineer one for em... so I had better
research it.

### I did see some info on C input 3 phase HV supplies some
where.... it's in Orr's older books.... but not alot of info.
Seems to me he had the 3 x primary's connected in a "Delta".....
and the 3 x secondary's tied in a.. "star". The rectifier set
up... if I remember, sorta looked like just 2 x diodes per sec
winding... one flipped around If I remember. The RMS voltage
per sec winding vs no load HVDC output is what threw me.
With say a 1 kv sec.... I'm positive... the OCV hv wasn't 1414
Vdc. [I may well be wrong with this.. just going by memory]

On Oct 3, 2006, at 3:49 PM, n6jp wrote:

I wonder if 'Z' is the c.s. administrator of the old amps group on
contesting.com?

Could well be.

Har, he really shot himself in the foot. He's now
the administrator of a defunct group. He might as well retire, he
won't have anyone to administrate to now but himself!

Hey 'Z' is your name Tom?

chortle. The laugher is that the "Administrator" / censor who jackboots folks out of AMPS for not giving a callsign, does not give a callsign himself.

If Tom joins this discussion group, I would definitely not be disappointed.

....

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

On Oct 3, 2006, at 5:13 PM, Mike Sawyer wrote:

Will, et al,
I challenged the 'administrator' about what calls for being banned from the list. Included were email lists and having a 'lack' of a call sign. Neither one, I pointed out were part of the list's own rules/regs. But that was another day. I'm about ready to "vote with my feet." My only regret is that it isolates some very good technical knowledge that hasn't found its way over here (yet).

Some of those with good technical knowledge are Tom's pals. My take on Tom is that he attracts people who share a common element in their childhoods. Apparently, the attraction is so strong that a number of the technically enlightened will not comment about statements such as Ni-Cr alloys have reverse skin effect at HF.

Mod-U-Lator,
Mike(y)
W3SLK

----- Original Message -----
From: craxd
To: ham_amplifiers@...
Sent: Tuesday, October 03, 2006 8:06 PM
Subject: [ham_amplifiers] Re: Hi-

I know of several that tried and the post never made it. Two did, but
the rest went bye bye. The unnamed, "no-callsign either" moderator,

chortle. My guess is that his callsign is W8JI since W8JI knew why I was booted out when no one else did. Also, the posts I wrote that questioned Tom's questionable technical statements were censored like clockwork.

who was on me about showing a callsign, has his eye on every post that
comes into Amps mainly to protect one person for any, well lets say,
embarrasing moments.

Indeed. If it walks like a duck, and it quacks like a duck, ... ...

When a groups moderator censors others posts who contradict one that
is plainly wrong, allowing the wrong comment to show, and not the
correct one, it's not a place to be.

Indeed. However, AMPS was started to protect Tom from what happened on rec.amateur-radio.homebrew in Fall, 1996 - where there was no censor to throttle those who questioned Tom's technical missteps.

Correct being that the one
posting it actually knows what they are talking about! : ) It's even
worse when the moderator lets the one in question take pot shots at
others, and when they reply, the post gets canned before the others
can see it.

The founding fathers of the United States thankfully realized that Censorship is poison.

Now, I admit, I was one of the ones that was guilty of e-mailing
everyone in my address book and bypassing the moderator. The moderator
aimed that one admonishment about harvesting e-mails at two people,
Rich and myself. However, this moderator must think that neither of us
has an address book on our own without his so-called "harvesting"
going on. I thought I still have the right, by the 1st amendment, to
e-mail anyone I damn well wish. I'm not aware that has EVER been
changed.

Moderators/censors/control-freaks dislike being bypassed because it neutralizes their control over others.

Sincerely,

Will

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

On Oct 3, 2006, at 2:40 PM, zerobeat40 wrote:

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

--- In ham_amplifiers@..., "zerobeat40" <zerobeat40@>
wrote:

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

wrote:

As I understand it, announcements of this group's existence on

the

AMPS group were somewhat censored.

Your understanding is incorrect. There were several

announcements

of

this group, as well as the larger more-established rfamplifiers

group

on Yahoo that made it to AMPs. Everytime someone posted on this

group

that "my announcement did not get posted", I looked at AMPS -

and

it

was, in fact, posted.

### DREAM ON. I checked 'amps' on contesting .com 3

times

now.... with a microscope [pulling up their archives]..... it

ONLY

got posted TWICE..... once from Mike... once from Alek

later........Jim VE7RF

Yes, that is the distinct number of people who claimed to have
attempted to post it and claimed that it was not posted.

I heard from others who said they tried to post the info about the
new group and it did not not get past the censor.

Thank you for the corroborration.

Z

Yet another unidentified station.

Yahoo! Groups Links

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

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

开云体育

I know of several that tried and the post never made it. Two did, but
the rest went bye bye. The unnamed, "no-callsign either" moderator,
who was on me about showing a callsign, has his eye on every post that
comes into Amps mainly to protect one person for any, well lets say,
embarrasing moments.

When a groups moderator censors others posts who contradict one that
is plainly wrong, allowing the wrong comment to show, and not the
correct one, it's not a place to be. Correct being that the one
posting it actually knows what they are talking about! : ) It's even
worse when the moderator lets the one in question take pot shots at
others, and when they reply, the post gets canned before the others
can see it.

Now, I admit, I was one of the ones that was guilty of e-mailing
everyone in my address book and bypassing the moderator. The moderator
aimed that one admonishment about harvesting e-mails at two people,
Rich and myself. However, this moderator must think that neither of us
has an address book on our own without his so-called "harvesting"
going on. I thought I still have the right, by the 1st amendment, to
e-mail anyone I damn well wish. I'm not aware that has EVER been
changed.

Sincerely,

Will


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

On Oct 3, 2006, at 2:40 PM, zerobeat40 wrote:

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

--- In ham_amplifiers@..., "zerobeat40" <zerobeat40@>
wrote:

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

wrote:

As I understand it, announcements of this group's existence on

the

AMPS group were somewhat censored.

Your understanding is incorrect. There were several

announcements

of

this group, as well as the larger more-established rfamplifiers

group

on Yahoo that made it to AMPs. Everytime someone posted on this

group

that "my announcement did not get posted", I looked at AMPS -

and

it

was, in fact, posted.

### DREAM ON. I checked 'amps' on contesting .com 3

times

now.... with a microscope [pulling up their archives]..... it

ONLY

got posted TWICE..... once from Mike... once from Alek

later........Jim VE7RF

Yes, that is the distinct number of people who claimed to have
attempted to post it and claimed that it was not posted.

I heard from others who said they tried to post the info about the
new group and it did not not get past the censor.

Thank you for the corroborration.

Z

Yet another unidentified station.

Yahoo! Groups Links

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

On Oct 3, 2006, at 2:40 PM, zerobeat40 wrote:

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

--- In ham_amplifiers@..., "zerobeat40" <zerobeat40@>
wrote:

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

As I understand it, announcements of this group's existence on

the

AMPS group were somewhat censored.

Your understanding is incorrect. There were several announcements

of

this group, as well as the larger more-established rfamplifiers

group

on Yahoo that made it to AMPs. Everytime someone posted on this

group

that "my announcement did not get posted", I looked at AMPS - and

it

was, in fact, posted.

### DREAM ON. I checked 'amps' on contesting .com 3 times
now.... with a microscope [pulling up their archives]..... it ONLY
got posted TWICE..... once from Mike... once from Alek

later........Jim VE7RF

Yes, that is the distinct number of people who claimed to have
attempted to post it and claimed that it was not posted.

I heard from others who said they tried to post the info about the new group and it did not not get past the censor.

Thank you for the corroborration.

Z

Yet another unidentified station.

Yahoo! Groups Links

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

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

High value wire-wound resistors have a well deserved

reputation for opening up - even when operated well within the
mfg's max-V rating.

### depends how they are mounted and or supported. The newer 5%
tol units made by Ohmite, IRC, clarostat, dale etc... have never
given me any problems. You can get high wattage, metal
finned units... from dale etc.... dunno about v rating.

### If really paranoid... GLOBAR makes a complete line of low +
high wattage non inductive HIGH VALUE resistor's.

## I have also seen where two separate strings of bleeders were
used. In the 3 k-ultra case.... use 40 k units. You would still
end up with the same 100 k in total.... but if one resistor
anywhere ever opened.... you are UP to 200 k total..... still
better than a wide open. A better scheme is to use the same
10 x 40 k resistor's.... but wire em series/parallel. Then if
any ONE resistor opened up anywhere.... you only go UP to 120 K
total... slick... and would work good. Damn good idea... dunno
why I didn't think of it b4 !

### Just replace all 5 of em... I doubt you will have any more
problems. It would be very interesting to see what value of
resistance... the 4 x remaining old ones are ??? If they
drifted... the highest value one would be the hottest. They
were/are running blazing hot as is. A 100 w rated wire wound..
diss 60 w is HOT.

Later... Jim VE7RF

On Oct 3, 2006, at 4:07 PM, pentalab wrote:

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

Indeed, and it's all because of greed. . During the recent
heat wave in Southern California, transformers were popping like
popcorn in residential areas because Southern California Edison
originally cut costs by installing transformers that were Way too
small. For example, on our block, a 50kva transformer supplies
power to c. a 200kva max load. During one heat spell, the
transformer got so hot it broke a seam and started to leak coolant
oil. Edison's fix was to replace it with another 50kva unit.

### The BIGGEST pole mount xfmr is 100 KVA. When u see one up
close... they are huge.. and heavy..... and when u see 3 x 100 kva
xfmr's all on the same pole.... then realize the total weight is
imense.

## Anything bigger than 100 Kva.... then they put em on the
grnd... partially sunk into the grnd ..in a kiosk. Most grnd
mount xfmr's don't have oil. SOME do.... some have
recirculating external oil pipes. You see em at shopping malls,
etc.

## My electrical buddies were telling me how big the primary
fuses are on these pole pigs....you do the maths....most would
melt b4 any fuse ever blew.

### For a single phase RF deck that needs say 6900V @ 3A...

a bare minimum of 34 uf will provide barely 3% ripple.

A 100 uf filter will provide 1% ripple... and far better
DYNAMIC Regulation.

RICH SEZ...And nobody on the Rx-end can hear the difference, Jim.

### On ESSB, you sure can..... and if you want good ssb audio on
a yaesu MK-V...check out the 85 page Document W5CUL and myself
wrote. It's on and also
[under mods]

### Once you modify these xcvr's.... they sound like AM broadcast
stations.... I'd say a lot better.

### BTW... ut FT-1000-D is only flat on RX... up to get this...
900 hz... then it rolls off above that !

### On TX we feed the analog BM directly [via a jensen xfmr]
On RX, we tap off the analog ssb product detector... and take it
external. The DSP in the yaesu MK-V is joke. When u toggle
between the analog mode and dsp mode... there is a 20 db RISE in the
TX noise floor... with mic gain on zero. The built in yaesu mic
pre-amp adds another TON of noise.... worst mic pre-amp ever.

### The stock yaesu RX af circuitry... AFTER the analog ssb
product detector leaves a lot to be desired.

## IMO... why listen to bad ssb audio, when it's so easy to
improve it.

Later... Jim VE7RF







Yahoo! Groups Links

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

On Oct 3, 2006, at 3:20 PM, pentalab wrote:

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

To see how much ripple was noticeable on the air, a friend put a
4-1000A on the air with a 6kV FWB PS running a 2uF C-filter. I

could

not hear any ripple -- at least on
SSB. AM would likely have been different.

### The ripple with say 2 uf and 6 kv @ 800 ma

Om SSB, it's about a third of that.

should have
been VERY noticeable........ unless of course your xcvr chops off
all the audio below 300 hz.

My receiver has a tunable IF, so i could hear through the zero beat

You can hear 120 hz ripple plane
as day on ESSB.

He did not have noticeable ripple with voice modulastion.

## 6 kv and a 2 uf C input filter would result in real bad
dynamic HV regulation !

### I used 16 uf [with a 2 holer 4-1000] which resulted in 3%
ripple.. I then increased it to 48 uf.. and 1% ripple could be
obtained.

### BTW... my co-hort's tell me that most of these Microwave
oven's all have one 1-uf 5KV oil cap in em. I know one
fellow who paralled about 3 x doz of em... it worked.

Later... Jim VE7RF







Yahoo! Groups Links

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

There will be no improvement as long transmitting bandwith is limited or
with poor audio response.
In Germany we are limited to 2,7KHz bandwith anyway, except on 10m.

73
Peter

________________________________

From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of pentalab
## IMO... why listen to bad ssb audio, when it's so easy to
improve it.

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

Indeed, and it's all because of greed. . During the recent

heat wave in Southern California, transformers were popping like
popcorn in residential areas because Southern California Edison
originally cut costs by installing transformers that were Way too
small. For example, on our block, a 50kva transformer supplies
power to c. a 200kva max load. During one heat spell, the
transformer got so hot it broke a seam and started to leak coolant
oil. Edison's fix was to replace it with another 50kva unit.

### The BIGGEST pole mount xfmr is 100 KVA. When u see one up
close... they are huge.. and heavy..... and when u see 3 x 100 kva
xfmr's all on the same pole.... then realize the total weight is
imense.

## Anything bigger than 100 Kva.... then they put em on the
grnd... partially sunk into the grnd ..in a kiosk. Most grnd
mount xfmr's don't have oil. SOME do.... some have
recirculating external oil pipes. You see em at shopping malls,
etc.

## My electrical buddies were telling me how big the primary
fuses are on these pole pigs....you do the maths....most would
melt b4 any fuse ever blew.

### For a single phase RF deck that needs say 6900V @ 3A...

a bare minimum of 34 uf will provide barely 3% ripple.

A 100 uf filter will provide 1% ripple... and far better
DYNAMIC Regulation.

RICH SEZ...And nobody on the Rx-end can hear the difference, Jim.

### On ESSB, you sure can..... and if you want good ssb audio on
a yaesu MK-V...check out the 85 page Document W5CUL and myself
wrote. It's on and also
[under mods]

### Once you modify these xcvr's.... they sound like AM broadcast
stations.... I'd say a lot better.

### BTW... ut FT-1000-D is only flat on RX... up to get this...
900 hz... then it rolls off above that !

### On TX we feed the analog BM directly [via a jensen xfmr]
On RX, we tap off the analog ssb product detector... and take it
external. The DSP in the yaesu MK-V is joke. When u toggle
between the analog mode and dsp mode... there is a 20 db RISE in the
TX noise floor... with mic gain on zero. The built in yaesu mic
pre-amp adds another TON of noise.... worst mic pre-amp ever.

### The stock yaesu RX af circuitry... AFTER the analog ssb
product detector leaves a lot to be desired.

## IMO... why listen to bad ssb audio, when it's so easy to
improve it.

Later... Jim VE7RF

To achieve 1,5% ripple from a 6-pulse power supply of 5KV at 3A you will
need a capacitor of 0,32?F.
Without any cap ripple will be 4%.
You will not here any hum from a transmitter without capacitor in the
6-pulse capacitor when using sideband transmissions.
From a carrier you here little hum on zerobeat.

The formula to find C for the 3-phase bridge circuit is the same as for any
other circuit, just calculate C from XC by using 300Hz in the formula.
How the transformer is connected does not matter, usually the primary will
be delta for best efficiency and the secondary will be star connected.
You will have 2 diodes per leg. The voltage across one winding is dc/sqrt6.

I my 7KV 4A CCS P/S I use UGE1112AY4 diodes by IXCYS, 3 per leg, just scewed
one into the next.



The transformer secondary is 5KV +/-5%, +/-10% phase to phase, or 2887V
across one winding.
I use 2?F 10KV for smoothing and a crowbar overload circuit with it.

73
Peter


________________________________

From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of pentalab

Then, if we talk 3-phase supply and 6-puls rectifying,
lets say around 5 kV DC potential, how much glitch C
is needed to achieve 1.5 percent ripple?

### Dunno. You would only have 5% ripple with NO cap.... and
with a resonant choke set up.....you probably wouldn't need any
C at all ! [3 phase]

### IF no resonant choke setup... and just a straight C input
filter.... I'm guessing around 5-16 uf would be plenty. It
would also highly depend on the load.

### I haven't found any formulae for a C input filter HV
supply........ with 3 phase. I don't have access to 3 phase....
so never pursued it. It would be the ultimate setup. IF you
find anything... let me know... as I'm most interested. Somebody
is going to ask me to engineer one for em... so I had better
research it.

### I did see some info on C input 3 phase HV supplies some
where.... it's in Orr's older books.... but not alot of info.
Seems to me he had the 3 x primary's connected in a "Delta".....
and the 3 x secondary's tied in a.. "star". The rectifier set
up... if I remember, sorta looked like just 2 x diodes per sec
winding... one flipped around If I remember. The RMS voltage
per sec winding vs no load HVDC output is what threw me.
With say a 1 kv sec.... I'm positive... the OCV hv wasn't 1414
Vdc. [I may well be wrong with this.. just going by memory]

I wonder if 'Z' is the c.s. administrator of the old amps group on
contesting.com? Har, he really shot himself in the foot. He's now
the administrator of a defunct group. He might as well retire, he
won't have anyone to administrate to now but himself!

Hey 'Z' is your name Tom?

Jer

### DREAM ON. I checked 'amps' on contesting .com 3

times

now.... with a microscope [pulling up their archives]..... it

ONLY

got posted TWICE..... once from Mike... once from Alek

later........Jim VE7RF

Yes, that is the distinct number of people who claimed to have
attempted to post it and claimed that it was not posted.

Thank you for the corroborration.

Z

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

To see how much ripple was noticeable on the air, a friend put a
4-1000A on the air with a 6kV FWB PS running a 2uF C-filter. I

could

not hear any ripple -- at least on
SSB. AM would likely have been different.

### The ripple with say 2 uf and 6 kv @ 800 ma should have
been VERY noticeable........ unless of course your xcvr chops off
all the audio below 300 hz. You can hear 120 hz ripple plane
as day on ESSB.

## 6 kv and a 2 uf C input filter would result in real bad
dynamic HV regulation !

### I used 16 uf [with a 2 holer 4-1000] which resulted in 3%
ripple.. I then increased it to 48 uf.. and 1% ripple could be
obtained.

### BTW... my co-hort's tell me that most of these Microwave
oven's all have one 1-uf 5KV oil cap in em. I know one
fellow who paralled about 3 x doz of em... it worked.

Later... Jim VE7RF

--- In ham_amplifiers@..., Jan Erik Holm <sm2ekm@...>
wrote:

Then, if we talk 3-phase supply and 6-puls rectifying,
lets say around 5 kV DC potential, how much glitch C
is needed to achieve 1.5 percent ripple?

Forgot how to calculate it, must dig out books
to do it.

73 Jim SM2EKM

### Dunno. You would only have 5% ripple with NO cap.... and
with a resonant choke set up.....you probably wouldn't need any
C at all ! [3 phase]

### Seems to me.... WAY back on 'amps'.... somebody tried this....
and with NO HV cap installed on the output..... one leg of the
diode board would always blow out ! It needed just a little bit
of C to make things happy for some reason.[3 phase + resonant
choke.... NO output HV cap. ]

### IF no resonant choke setup... and just a straight C input
filter.... I'm guessing around 5-16 uf would be plenty. It
would also highly depend on the load.

### With NO load [just the eq resistor's across the lytics, etc...
which basicly is zip]... ripple is nil. The greater the
load.... the worse any ripple gets. You can see 3% ripple...
plane as day with a dead cxr, on any RF "monitor scope". Looks
like a small sine wave across both the top and bottom. Should
be a solid green bar.

### I haven't found any formulae for a C input filter HV
supply........ with 3 phase. I don't have access to 3 phase....
so never pursued it. It would be the ultimate setup. IF you
find anything... let me know... as I'm most interested. Somebody
is going to ask me to engineer one for em... so I had better
research it.

### I did see some info on C input 3 phase HV supplies some
where.... it's in Orr's older books.... but not alot of info.
Seems to me he had the 3 x primary's connected in a "Delta".....
and the 3 x secondary's tied in a.. "star". The rectifier set
up... if I remember, sorta looked like just 2 x diodes per sec
winding... one flipped around If I remember. The RMS voltage
per sec winding vs no load HVDC output is what threw me.
With say a 1 kv sec.... I'm positive... the OCV hv wasn't 1414
Vdc. [I may well be wrong with this.. just going by memory]

In any event... the entire concept looked cool .... which could
easily be implemented with either a 3 phase xfmr.... or 3 x
separate xfmrs. Dahl's diode boards for this appear to have
6 x legs for the entire mess.......... instead of 4 x legs for
single phase FWB..... which, incidently he rates at 18 A CCS....
using just standard 6A10 diodes [1 kv-6] diodes.

He rates a standard FWB.. with the usual 4 x legs at 12 A
CCS... using the same 6A10 1 kv-6A diodes.

Now 6 A x .8 V = 4.8 watts.... which would get VERY hot.
I experimented with mine.. in a test jig... just pumping low V
DC... and a variable lab supply + a 25 ohm-225 w resistor... and
found that the 1N5408 [1 kv-3A] would run luke warm with 1 A
CCS... and hot at 2A... and smokin hot at 3 A. Similar results
with the 6A10 [6 A- 1 kv]... runs luke warm with 2 A CCS...
hot
with 4 A.... and smokin hot with 6A.

Commercial rectifier assy's using these diodes... some of em
will blow 100 cfm across em.... if u want to run em anywhere
near maxed out.

I also tried paralleling 3A diodes for more current [and also
6A diodes] .. Done easily... and the current split is
virtually 50-50. So I don't understand the ARRL handbook insisting
installing series resistor's in each leg for balancing ? I
also tried paralleling two separate, identical bridge rectifier
assys.... same results.

One other note... Just by hooking a test clip lead on the very
1st and very last diode.. while doing my heating tests... I
found that the 1st and last diode ran barely warm.... while the
rest of em ran hot. The leads out each end of these diodes IS
the heatsink.... so don't cut em off short.... they either have
to go along aways horizontally b4 doing a right angle into the
board... OR go straight through the board... and keep going in mid
air below the board 1" to 1.5"

Later.... Jim VE7RF

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

--- In ham_amplifiers@..., "zerobeat40" <zerobeat40@>
wrote:

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

As I understand it, announcements of this group's existence on

the

AMPS group were somewhat censored.

Your understanding is incorrect. There were several announcements

of

this group, as well as the larger more-established rfamplifiers

group

on Yahoo that made it to AMPs. Everytime someone posted on this

group

that "my announcement did not get posted", I looked at AMPS - and

it

was, in fact, posted.

### DREAM ON. I checked 'amps' on contesting .com 3 times
now.... with a microscope [pulling up their archives]..... it ONLY
got posted TWICE..... once from Mike... once from Alek

later........Jim VE7RF

Yes, that is the distinct number of people who claimed to have
attempted to post it and claimed that it was not posted.

Thank you for the corroborration.

Z

--- In ham_amplifiers@..., "zerobeat40" <zerobeat40@...>
wrote:

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

As I understand it, announcements of this group's existence on

the

AMPS group were somewhat censored.

Your understanding is incorrect. There were several announcements

of

this group, as well as the larger more-established rfamplifiers

group

on Yahoo that made it to AMPs. Everytime someone posted on this

group

that "my announcement did not get posted", I looked at AMPS - and

it

was, in fact, posted.

### DREAM ON. I checked 'amps' on contesting .com 3 times
now.... with a microscope [pulling up their archives]..... it ONLY
got posted TWICE..... once from Mike... once from Alek

later........Jim VE7RF

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

On Oct 2, 2006, at 5:58 PM, pentalab wrote:

### Yes HSU. We were wondering why it took you so long to find
us !! LOL

As I understand it, announcements of this group's existence on the
AMPS group were somewhat censored.

Your understanding is incorrect. There were several announcements of
this group, as well as the larger more-established rfamplifiers group
on Yahoo that made it to AMPs. Everytime someone posted on this group
that "my announcement did not get posted", I looked at AMPS - and it
was, in fact, posted.

Z

On Oct 3, 2006, at 5:54 AM, ad4hk2004 wrote:

Rich I took a look... The resistors are L100J-20K rated 2850 volts
max.. It is a string of five in series, so I see no problem... Perhaps
you were thinking of a different resistor, but thanks for the heads up...

High value wire-wound resistors have a well deserved reputation for opening up - even when operated well within the mfg's max-V rating.

cheers, Denny

denny / k8do







Yahoo! Groups Links

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