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

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...

denny / k8do

Hi Group,

Anyone have the schematic and hookup info for the Alpha 99 HV transformer that you could send electronically?

I have downloaded the manual from Alpha but it does NOT include any schematic or info on the transformer connectors.

Thanks in advance for your help!

73, Tony W4ZT
tony
at
w4zt
dot
com

Ummm, no... Thought didn't occur... I will do that but I unlikely I
will make a change...
One resistor got hot in the middle of the winding, bubbled the coating
over a distance of about an inch and a half, being exposed to the air
oxidized the nichrome wire and it finally burned in two... Then the
fireworks started with crap being arc sputtered all over the PS...
Being the RF box is in a different room of the shop than the radios, I
heard/noticed nothing until I happened to idly look the HV while in
receive... Eyes got wide and I hastily hit the main breaker on the
wall by my left hand (planned that way for stuff such as this) The
other 4 resistors look fine, no sign of overheating... I am going to
change out the whole rack of 5, but that is just because I'm an old
woman about minor things - spent part of my wasted youth maintaining a
herd of 100KW RF generators and a pinch of prevention stops a whole
bunch of lost production time...
It looks to me to be a manufacturing defect in the resistor as opposed
to deficient design... ( Brand was HEI 9352, possibly a spot welded
wire join in the winding? - dunno. )
I know contesting groupies go on about Henry's supposed design
deficiencies, but I have to say until this incident this amp has given
a dozen years of solid contesting service... The high voltage
stabilization is/was stiff... Since I don't jump from band to band in
a contest the slow tuning is not an issue... I have been happy with it...

denny / k8do

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

--- In ham_amplifiers@..., "Hsu" <Jbenson@...> wrote:

Hi,
I have join the list.Thanks for many friends Invitate me to

ham_amplifiers.

Hsu

### 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.

### You can talk about 811-A's all you want here. And nobody is
going to suggest boycotting Chinese made products, Chinese gov't,
or Chinese radio amateur's either !

Welcome aboard.....
Later.... Jim VE7RF








Yahoo! Groups Links

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

On Oct 2, 2006, at 3:25 PM, pentalab wrote:

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

What is your reason for that large capacitor?
Are you using single phase at that power level?
I only use 2?F maximum or NONE in my large power supplies, so my
glitch resistors and magnetic breakers in the primaries of the
transformers is all I need

73
Peter, DF3KV

### You gotta be kidding us right ?? 2 uf or NONE !!

2uF in a FWB is enough for a 4-1000A at 6kV.

### here in NA... although 3 phase power [typ 12.5 kv /14.4 kv
and now 25 kv] is distributed all over town..... only one
leg /phase of that appears in residential area's.... where it's
dropped down to 240 /120 v [ they all use a grnded CT on the
sec]

### Typ pole pig xfmrs are 25/50 kva for multiple homes.. and
smaller for a single home in the countryside. How 16 homes
can all share the same 50 KVA xfmr [and all have "200 A"
service] is beyond me !

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.

### 3 phase 208v/120v is used for business's.... and
condominium's, apartment flats etc. Even there.... each floor will
only get 208/120 single phase power... per suite. They make
special 208 v electric base board heater's. Stuff like 240 v
electric stoves.. and 240V electric hot water tanks/ 240 v
electric clothes dryer's.. are used on 208 v.... and just take a
little longer to heat up.

### 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.

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

...

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