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

Hal,

I'd give Ed a call at Heritage Transformer in Kentucky, or the

guys

at Galaxy Transformer in New Jersy.

I take it this will be a resonant filter choke? If so, it's best

to

send them the cap your going to use, and then they can wind a

choke

that will for sure work with it.

#### Highly agreed.



No matter the math used to calculate

a resonant choke circuit, sometimes it's hard to get this to work
right. Since the cap is a fixed unit, the windings of the choke

can

be played with to make sure it does come into resonance at the
specified load current. The winder needs the cap to be used though

so

the choke can be wound correctly to match it. Buying an off the

shelf

choke may not work as you intend it to.

### I concur. John Lyles sez to ALWAYS send in the cap to the
choke builder... and let THEM resonate the combo. Make sure the
cap is good... and has a high enough V rating, etc. They never
resonate the combo at 120 hz either...[the cap will BLOW UP]....
they always resonate em a few HZ higher... like 125 hz.

### Max ripple occurs with Max load. I'd like to know what
happens if say the cap goes bad 10 yrs down the road...... can u
just stick in another cap ? Probably best to MEASURE the
ORIGINAL cap... BEFORE shipping it off. [with an LCR meter]...
and WRITE IT DOWN... stick in ur file.. make multiple off site
copies etc.

### Then if the cap ever needed replacing.... you can measure some
new ones... and find one that's the same value... or err on the
side of slightly LOWER value cap from original measured cap.
That way.... the combo would still resonate at same or slightly
HIGHER freq... and not LOWER.... which would be a disaster.

## Ask Rauch. He resonated his at exactly 120 hz.... and
almost blew himself up ! He's been down on resonant choke
filters ever since then! He may have even.."wrote a paper" on it.
That was apparently a million yrs ago.

Later... Jim VE7RF

Best,

Will


--- In ham_amplifiers@..., "hbmandel" <ka1xo@> wrote:

Without mentioning a familiar Texan, would somebody suggest
a source for a 12 henry choke with 13 ohms or less D.C.

resistance,

able to handle 2.25 amperes with an a.c. voltage input of 3,000

volts?

The unit will be resonated with a .211uH, 10KV capacitor and

will

form

the input of an anode power supply.

Thanks,

Hal Mandel
W4HBM

On Nov 21, 2006, at 3:58 PM, pentalab wrote:

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

On Nov 21, 2006, at 1:26 AM, badgerscreek wrote:

RICH SEZ... Which is why I used a 40A thermal-magnetic

breaker for

the 8170 amp.

...
### I can see by juggling the trip curve ratings... one could use
an underated breaker on ssb/cw.... which would then pop open with
a 2-7 second dead cxr.

? The only time that the Plywood Box 8170 amplifier was keyed down
was when Terry, W6RU, wanted to see if doing so would peg his avg
reading Bird wattmeter. When the WM pegged, the amplifier was
unkeyed so that the 40A breaker would not trip.

What all this indicates is that low rated breakers could handle

the current. Your foolish if you rely on a breaker alone to protect
your expensive tube and other electronics.

? In an amplifier with an indirectly heated cathode type tube, like
the 8877, an anode fuse can, if it is properly sized, prevent
stripping the cathode's emissive coating when drawing excessive
cathode current. However, if the tube has a directly-heated cathode,
such as an 8171, the W^2C [ditungsten-carbide] emissive layer on the
cathode can not damaged by excessive cathode current -- plus such
tubes are naturally current-limiting. Thus, for tubes with thoriated-
tungsten filaments, the bottom-line is that an anode fuse is a waste
of time.

RICH SEZ... Indeed. The glitch-R protects the tube.

### agreed... provided it has enough resistance. 30-60 ohms will
work..

? With a pair of 3-500Zs @3kV, a glitch-R of as little as 10-ohms
appears to prevent filament-to-grid shorts.

. the more the better... up to a point.. till diss gets too
high.. and /or v drop gets to be too much.... or both.

? On the air tests have shown that a 40% drop in HV (c. 1.5db in
signal strength) is not discernible on the Rx end due to normal QSB.

I have witnessed a 8171 being tuned with a pulser to 15 kw out

using a 40 amp breaker. What I do know is that if the tube flashes
or faults, or the screen supply fails the breaker will trip. With a
good glitch R its only a matter of changing a 1.5 amp screen supply
fuse and resetting the breaker.

### agreed... but I still think any amp should be capable of at
least a 2-7 second dead cxr for various under load measurements.

? Could this perhaps be an ego-trip? As I see it, if an amplifier
is designed for SSB use, there is no reason to subject it to dead-
carrier abuse.

.

If you using something like a grounded screen tetrode,

complicated

circuit protection schemes can be dangerous and very

unreliable.

Everything is floating at 1500 volts below chasis potential!

Indeed. A screw-adjustable spark gap set to c. 2000v in series

with

an ohm or three puts the brakes on as needed.

### An adjustable spark gap will work.

RICH SEZ...Another method is sacrificial diodes: Put two 3A or
better diodes in series whose measured piv is c. 2000v total.
When the potential goes above 2000v, the diodes avalanche and
short, preventing the DC-floating cathode circuit from typically
spiking to neg. 7 - 9 kV.

### whoa. I once had an arc from glitch R [input side] to the
junction of diodes #4 and #5 on leg 4 of a FWB [15 x diodes
per leg] on my pole pig HV supply. The entire diode board
would pivot on it's center axis, to allow getting access to the
terminals of the 4 x oil caps directly below the board.[extremely
tight fit] One day... I forgot to pivot the diode board back to
level... and the arc occured. What happened was the +6700
vdc , when applied to junction 4 + 5 of the diodes.. was going
through the last 4 x diodes... BACKWARDS... their combined 4 kv PIV
was exceeed... and all 4 blew clean in 1/2 !! IF the diodes
were mounted E-W.... they split N-S. That's my experience
with exceeding the PIV ratings of diodes... and by not very
much. Exceeding their current ratings... when 'turned on' as
in protection diode service.... they just short out... zero
physical scares. Rich... I'd stick with ur adjustable spark gap
set up... dunno if u need the 1-3 ohms in series with the spark gap
or not. They might fry too.

? Not if it's tough enough. As I see it, all snubber circuits
benefit from a little R.

...
...
### Point is... you may need to suck 100 A on voice peaks on
one amp.... and only 1/2 that on another amp... and maybe only 10-
12 A on a 3-500Z amp. One breaker in the 240 V line, sized for a
15 kw amp is now gonna be too big for a 1500w amp.....

? My SB-220 does not have a 50A/240V #6 Cu electric-range cord set.

cheers, Jim

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

On Nov 21, 2006, at 3:25 PM, Mike Sawyer wrote:

I guess I'll pile on here too. When Joe, W4TV went on his Rich tirade, I
responded by telling him, in more or less words, that he was way off base. I
got a reply from Tom Rauch that said, "Mike, don't you think you were a
little hard on Joe?" I was flabbergasted and just responded with, "You got
to be kidding me!"

Drinkin' buddies stick together pretty tightly, Mike.

...

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

On Nov 21, 2006, at 4:47 PM, craxd wrote:

Hal,

I'd give Ed a call at Heritage Transformer in Kentucky, or the guys
at Galaxy Transformer in New Jersey.

I take it this will be a resonant filter choke? If so, it's best to
send them the cap your going to use, and then they can wind a choke
that will for sure work with it. No matter the math used to calculate
a resonant choke circuit, sometimes it's hard to get this to work
right. Since the cap is a fixed unit, the windings of the choke can
be played with to make sure it does come into resonance at the
specified load current.

As I understand it, the gap-width is adjusted to fine-tune the L.


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

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

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

I got an e-mail from the unknown admin
chastizing me over questioning Tom and what they called other
published engineers.

### so what exactly did Tom publish..... besides Ameritron

manuals?


Jim, I think he may have sent something in to QST one time. However,
comparing something sent in to QST and a true scientific paper is
like comparing apples to horse turds IMHO. There's been some good
ones, but there's been some real screw ups too. Some was the fault of
the QST editorial staff.

### They had this silly roaring discussion on 'AMPS' 2 weeks
ago.... the poor fellow asking the question gets chastised by a

guy

in 9 land ... "Tom rauch already gave u the answer... just ignore
the other 24 reply's" So I guess if u post on AMPS... the only
valid reply is Tom.

That's the very reason I hardly ever post there anymore. At that, I
don't ever see Toms posts as I have him set up in my junk mail
filter. The only way I see anything is from someone else replying to
one of his posts. I found that the best way to defeat him was simply
to ignore him and not to reply to one word he says.

### another fellow I know.. Ken W2DTC wanted to know how much
anode diss is required for a 1500 W pep output linear... running
class A... on AM. They went off on a tangent.. and then some.
Correct answer of course is just 1500/.25 = 6 kw pep input.
PEP Anode diss is of course.. 6000-1500 = 4500 w. Keyed..
with NO modulation... it becomes 6000-300/375 = 5700/5625 w...
CCS diss. A single 3x3 won't do it either. A pair of em
will.. or a single 3x6... or something bigger still. Slick way
to justify a big tube in the shack imo. I emailed Ken... he
agreed... I had nailed it.

### Rauch never did get that one right... neither did the

secret

admin.... nor anyone else.



When this didn't work with me, he went so low as to try and

question my education. When I told him what to do with his

question, the admin privately e-mailed me the chastizing e-mail.

### Maybe some of these guys with fancy degrees..... should ask
for their money back ! IMO, designing and building a linear is
nothing more than a high school science project.... not rocket
science. It's all old news. Some of the implementation
techiniques used these days are sorta new.... for hams.

I highly doubt Tom has a degree. If he did finally receive one, he
slept through some pretty important classes. He told Rich he never
took a course in AC analysis I think it was.

I have the equivelant of an associates in electricity and electronics
which is about all you can get through a state Vo-Tech (or was at the
time), and a BSc in mechanical engineering from Washington
International University. I received it through earned work credit
and a two year corrospondence course after I had started working in a
mechanical engineering department.

He has claimed to have worked with Heathkit, but when asked about
what he did, he chose to ignore the question.

As Paul Harvey said, "... and now you know [pause] the Rest of

the

Story."

#### This grp is up to 180 now... and climbing daily.

Later... Jim VE7RF

Best,

Will

Best,

Will

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

### another fellow I know.. Ken W2DTC wanted to know how much

anode diss is required for a 1500 W pep output linear... running
class A... on AM. They went off on a tangent.. and then some.
Correct answer of course is just 1500/.25 = 6 kw pep input.

RICH SEZ...? Why would anyone want to run Class-A AM when the

average AB2 g-g amplifier is cleaner than almost any transceiver?

### Cuz it's legal. In GG.. with little or no bias with a
triode... and LOTS of no load HV... ZSAC is through the roof...
amp runs CLASS A... squeaky clean for the fellows with yaesu Class
A xcvr's, etc. It would work on SSB as well as AM. On AM...
with NO modulation BUT keyed... plate diss = 5625-5700 W CCS. On
SSB... keyed up.. no drive.... plate diss should be even worse.. a
full 6 kw. Point here is it's legal... and a very convenient
way to justify ur BIG tube... when Riley H comes a poundin on
ur door some day. Dunno about ur regs... but we measure power
AT the ANT... not the amp... IE: AFTER feedline loss.

### That being the case.... one could EASILY add another 1-2 db
on top of all this mess. 2db = 34 % loss Joe ham now
requires 2250 W PEP from his CLASS A linear.... to get a meager
1500 w PEP at the top of the tower. 2250/.25 = 9 kw PEP
input.... and of course... on SSB... keyed with NO drive applied...
means 9-kw of CCS anode diss ! Quick.. dump that 3x6.... and
race out and get a bigger tube.

### Hey Rich... seems to me ur latest 4x10J project sez just
that.... "1500W clean CLASS A output" Accidently turn up the mic
gain on a grid driven tetrode... and then it's 10 db more.

### What's Riley H gonna do next... outlaw class A linears ??

PEP Anode diss is of course.. 6000-1500 = 4500 w. Keyed..
with NO modulation... it becomes 6000-300/375 = 5700/5625 w...
CCS diss. A single 3x3 won't do it either. A pair of em
will.. or a single 3x6... or something bigger still.

? An 8281?

### Yes... that will work nicely.

When this didn't work with me, he went so low as to try and

question my education.

? This is pretty much SOP for Rauch and his groupies. And this

from

a guy who has never bothered to take a course in AC circuit
analysis. Low? They suggested that I was humping the 17-yr old
girl who worked for me at the time.

### You told me she was.. "hot" Perhaps Rauch et all thought
she was working too much over time. I remember Tom poo pooing
ur huge order's from Digi-key /mouser. Meanwhile, the wire
wounds on Ameritrons ran hot.... opened up.... and bye bye lytic
strings. Ameritron's answer of course was to ship it back to the
factory/dealer..[where 'factory experts' can diagnose the[ir]
problem], replace all the caps... and replace the 1-2 open
wire wounds... with new wire wounds... ship it back..... then
repeat the sequence. [this is all out of warranty of course, at
joe ham's expense]

Later... Jim VE7RF

Hal,

I'd give Ed a call at Heritage Transformer in Kentucky, or the guys
at Galaxy Transformer in New Jersy.

I take it this will be a resonant filter choke? If so, it's best to
send them the cap your going to use, and then they can wind a choke
that will for sure work with it. No matter the math used to calculate
a resonant choke circuit, sometimes it's hard to get this to work
right. Since the cap is a fixed unit, the windings of the choke can
be played with to make sure it does come into resonance at the
specified load current. The winder needs the cap to be used though so
the choke can be wound correctly to match it. Buying an off the shelf
choke may not work as you intend it to.

Best,

Will


--- In ham_amplifiers@..., "hbmandel" <ka1xo@...> wrote:

Without mentioning a familiar Texan, would somebody suggest
a source for a 12 henry choke with 13 ohms or less D.C. resistance,
able to handle 2.25 amperes with an a.c. voltage input of 3,000

volts?

The unit will be resonated with a .211uH, 10KV capacitor and will

form

the input of an anode power supply.

Thanks,

Hal Mandel
W4HBM

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

On Nov 21, 2006, at 1:26 AM, badgerscreek wrote:

RICH SEZ... Which is why I used a 40A thermal-magnetic

breaker for

the 8170 amp.
...

What Rich Says may be possible its all in the detail..

### agreed. It all depends on average current drawn during ssb.
On CW however... I set my dashes up for 3.6 to 4.0 times as long
as a dot. Sending dashes at 8-15 wpm really raises the average
current draw.

Most circuit breakers have 3 current tripping curves.

### are u talking about house breakers in the 200 A main
panel... OR controlled magnetic hydraulic types... mounted in the
HV supply or both? I have not researched what's available for
the main 200 A panel.

Curve A, B and C

Curve A trips roughly at 3 to 5 times the current rating.

Curve B trips at 5 to 10 times rated current

Curve C trips at 10 to 14 times current rating.

You also need to study the I Squared T ratings of the breakers.

### except for the real slow motor start Curve C/D
breakers... they should all trip at 110 % of their rating...
with CCS current.

### I can see by juggling the trip curve ratings... one could use
an underated breaker on ssb/cw.... which would then pop open with
a 2-7 second dead cxr.

What all this indicates is that low rated breakers could handle

the current. Your foolish if you rely on a breaker alone to protect
your expensive tube and other electronics. A Glitch R is advisable.

RICH SEZ... Indeed. The glitch-R protects the tube.

### agreed... provided it has enough resistance. 30-60 ohms will
work... the more the better... up to a point.. till diss gets too
high.. and /or v drop gets to be too much.... or both.

I have witnessed a 8171 being tuned with a pulser to 15 kw out

using a 40 amp breaker. What I do know is that if the tube flashes
or faults, or the screen supply fails the breaker will trip. With a
good glitch R its only a matter of changing a 1.5 amp screen supply
fuse and resetting the breaker.

### agreed... but I still think any amp should be capable of at
least a 2-7 second dead cxr for various under load measurements.


.

If you using something like a grounded screen tetrode,

complicated

circuit protection schemes can be dangerous and very

unreliable.

Everything is floating at 1500 volts below chasis potential!

Indeed. A screw-adjustable spark gap set to c. 2000v in series

with

an ohm or three puts the brakes on as needed.

### An adjustable spark gap will work.


RICH SEZ...Another method is sacrificial diodes: Put two 3A or
better diodes in series whose measured piv is c. 2000v total.
When the potential goes above 2000v, the diodes avalanche and
short, preventing the DC-floating cathode circuit from typically
spiking to neg. 7 - 9 kV.

### whoa. I once had an arc from glitch R [input side] to the
junction of diodes #4 and #5 on leg 4 of a FWB [15 x diodes
per leg] on my pole pig HV supply. The entire diode board
would pivot on it's center axis, to allow getting access to the
terminals of the 4 x oil caps directly below the board.[extremely
tight fit] One day... I forgot to pivot the diode board back to
level... and the arc occured. What happened was the +6700
vdc , when applied to junction 4 + 5 of the diodes.. was going
through the last 4 x diodes... BACKWARDS... their combined 4 kv PIV
was exceeed... and all 4 blew clean in 1/2 !! IF the diodes
were mounted E-W.... they split N-S. That's my experience
with exceeding the PIV ratings of diodes... and by not very
much. Exceeding their current ratings... when 'turned on' as
in protection diode service.... they just short out... zero
physical scares. Rich... I'd stick with ur adjustable spark gap
set up... dunno if u need the 1-3 ohms in series with the spark gap
or not. They might fry too.



I first used high speed semiconductor fuses, however they are
expensive and blow too fast for minor things like spider or dust
induced arcs.

### Minor things ? What's supposed to happen... the dust gets
vaporized... and the amp keeps working ?? I'd almost rather blow
some fuses/breaker's etc. Then perhaps vac or blow out with
compressed air. The semi conductor fuses are slick....albeit
expensive. They are FAST. "Rectifier" fuses are fast too... but
not quite as fast as a semi conductor fuse.

### another valid concern I have is when multiple HV taps are used
on a plate xfmr... for several voltages... usually lower... for
smaller tubes. HV taps on a HV xfmr can be switched via a 13 kv
TYPE 85/88 single wafer switch.[shut the pwr supply OFF 1st.. THEN
switch]... or if just toggling between any two taps.. a heavy duty
vac relay. In some cases.... multiple FWB's and more HV caps
can be used on lower V taps.... so several simultaneous voltages
can be had.

### Point is... you may need to suck 100 A on voice peaks on
one amp.... and only 1/2 that on another amp... and maybe only 10-
12 A on a 3-500Z amp. One breaker in the 240 V line, sized for a
15 kw amp is now gonna be too big for a 1500w amp..... hence
my idea of either supplemental semiconductor/rectifier fuses...
sized smaller... behind the BIG breaker.

### The other idea I had, works too. IE: removing the tie- bar on
a multi pole breaker... paralleling the contacts... and making 2
x such assys...... install one assy per hot leg. By shutting one
pole per assy off.... you just halved the breaker capabilty.

### With a pair of identical 3 x pole breaker's... you could
get 3 x levels of breaker ratings. [all 4 x tie bars removed on the
2 x breaker assys]

### Then u can do stuff like use all the poles for ur dead cxr
quickie test/FM/slow CW/AM/RTTY stuff..... and by knocking one/two
poles off per breaker....use it for ssb... making for a faster
overall trip IF something goes amsiss. Then u can have ur
cake..and eat it too.

### when u parallel poles of breakers, or wafer's on
bandswitches.. etc... for more current... u gotta do it right.... to
equalize the current draw. In on input of #1 pole/wafer... exit on
output of pole/wafer #2. Just make sure the individual poles
are rated for > 250 v. The voltage across one open breaker in
one leg with this config... is 240 V ..IF all poles in the 2nd
assy are intact. This could easily happen.... since the tie-bars
have been removed... one hot leg could open off... and the other leg
intact.... ditto with .."supplemental fuses".

Later... Jim VE7RF

Greg

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

I guess I'll pile on here too. When Joe, W4TV went on his Rich tirade, I
responded by telling him, in more or less words, that he was way off base. I
got a reply from Tom Rauch that said, "Mike, don't you think you were a
little hard on Joe?" I was flabbergasted and just responded with, "You got
to be kidding me!"
Mod-U-Lator,
Mike(y)
W3SLK

On Nov 21, 2006, at 1:15 PM, pentalab wrote:

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

I got an e-mail from the unknown admin
chastizing me over questioning Tom and what they called other
published engineers.

### so what exactly did Tom publish..... besides Ameritron manuals?

### They had this silly roaring discussion on 'AMPS' 2 weeks
ago.... the poor fellow asking the question gets chastised by a guy
in 9 land ... "Tom rauch already gave u the answer... just ignore
the other 24 reply's" So I guess if u post on AMPS... the only
valid reply is Tom.

? Tom is now the owner-operator / censor librorum.

### another fellow I know.. Ken W2DTC wanted to know how much
anode diss is required for a 1500 W pep output linear... running
class A... on AM. They went off on a tangent.. and then some.
Correct answer of course is just 1500/.25 = 6 kw pep input.

? Why would anyone want to run Class-A AM when the average AB2 g-g
amplifier is cleaner than almost any transceiver?

PEP Anode diss is of course.. 6000-1500 = 4500 w. Keyed..
with NO modulation... it becomes 6000-300/375 = 5700/5625 w...
CCS diss. A single 3x3 won't do it either. A pair of em
will.. or a single 3x6... or something bigger still.

? An 8281?

Slick way
to justify a big tube in the shack imo. I emailed Ken... he
agreed... I had nailed it.

? Guffaw

### Rauch never did get that one right... neither did the secret
admin.... nor anyone else.

? it's him, Jim.

When this didn't work with me, he went so low as to try and

question my education.

? This is pretty much SOP for Rauch and his groupies. And this from
a guy who has never bothered to take a course in AC circuit
analysis. Low? They suggested that I was humping the 17-yr old
girl who worked for me at the time.

When I told him what to do with his
question,

? why bother?

the admin privately e-mailed me the chastizing e-mail.

### Maybe some of these guys with fancy degrees..... should ask
for their money back ! IMO, designing and building a linear is
nothing more than a high school science project.... not rocket
science.

? True enough, Jim, but I didn't feel like I had a handle on it
until after 3-ys of college and I hit 42.

It's all old news. Some of the implementation
techiniques used these days are sorta new.... for hams.
...

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

On Nov 21, 2006, at 12:40 PM, pentalab wrote:

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

### A few good spikes down the power line and the diodes WILL
fail..

RICH SEZ...Only if the amplifier is on at the time and only if the

spike goes above 451 volts-pk. And, it hasn't happened in 20+
years.

..esp with only 33% more PIV....and little or no additional
protection.

RICH SEZ... No "protection" whatsoever because now I understand why.

### little or no additional protection means no big momma MOV's
on the 240 V line... NOT no hv fuses, glitch R, safety diodes,
etc.... and those devices are NOT gonna save ur diode stack from
a big spike coming in off the street. Spikes will pass through a
plate xfmr... like it wasn't there.

The filter C looks like a virtual short to short spikes.

### with a safety factor of only 33%.... the diodes would fry...
LONG before any MOV cliped the spikes off.

RICH SEZ...K5JV told me that he experienced a lightning strike

that blew two bolt'em-in MOVs clean out of the box and left them
smoking on the deck.

### Not big enough then!

Agreed, but some strikes exceed 100kA.

Where was the lightning hit..

to the HV power line down the alley about 200'.

. across
the street... onto the 14.4 kv line iteself or what ?

### For real protection... the 4" square x 1" thick MOV's should
be used... in a sub box..right at ur main 200 A panel... wired
each line to neutral. That's the 1st layer of protection.

Then.... install the bolt down MOV's at the plate xfmr pri
input.... both across the 240 line... and each side to
neutral/grnd. That's the 2nd layer of protection... ditto with
any power bars, etc for xcvr's, other gear.

...

RICH SEZ....You seem to assume that conduction for a 250v

rating begins at 251 x 1.14 volts. It does not.

### I already know that. Rich..... take a 0-277 v variac..... and
a 250 V rated MOV..... and apply >250 V on it for 1 hr...then
tell us what happens !

RICH SEZ... According to Panasonic spec, one their 250vac-rated MOVs
begins to conduct current at 390v +/- 10%. This is 278v-rms +/-
10%.

### Each Manufacturer of MOV's rates em a dif way. Some will rate
by joules... some by max peak current.. some both. Rise times will
vary... some will respond in 80 nanoseconds.. some 20.. some just
1 nano second. Some will take XXX peak amps.... for a specified
duration.... the duration will also vary, etc. Point here is...
don't take one type of Panasonic MOV... and use those specs.. and
apply to all other MOV's... doesn't work.

I am talking only about the point where a small amount of electrons begins to flow.

.....
### The whole point here is... with successive hits... the V

rating

of any MOV starts to drop... another reason we fuse em.

RICH SEZ...Agreed

### Most newer homes in Florida have giant MOV's located just

below the main 200 A service panel... connected to main Buss... via
a 20-60A breaker.

### I'm sure this is a house insurance co requirement in some
counties now. Insurance co's get tired of paying out for blown up
fridges, TV's... and everything else in your home... every time a
lightning storm happens... which is all the time in Florida...
lightning capital of the world.

Indeed, Jim.

...

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

Without mentioning a familiar Texan, would somebody suggest
a source for a 12 henry choke with 13 ohms or less D.C. resistance,
able to handle 2.25 amperes with an a.c. voltage input of 3,000 volts?

The unit will be resonated with a .211uH, 10KV capacitor and will form
the input of an anode power supply.

Thanks,

Hal Mandel
W4HBM

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

I think I'd want one to act fast at the trip current it's rated at.

### I concur.... get the FASTEST one available. Potter and
brumfield make two style versions's of em.. both panel mount with 6-
32 screws.... they both come in 1-2-3 pole.... from real low
curreent up to 50-A..... and in 3-4 x different trip curves.... from
super fast... to slowed... for motor start up. I think mine were
the WX series 2 pole type.

### Appears to be plenty of manufacturers out there who make em...
or a combo of thermal/magnetic too. Just make sure you size it
right. Figure on plate xfmr primary VA being at least 30% more
than DC input.... also factor in fil xfmr, blower's, any other
small supplies etc.

later... Jim VE7RF

, is it worth

investing in a magnetic-hydraulic circuit breaker,

and at what profile, (e.g., fast, very fast, ultra fast, etc.)?



Hal Mandel

W4HBM

I had bought out a Quasar dealership back in the early 80's and
repaired both Quasar and Panasonic products. At that time, Matsushita
really was proud of putting their name on everything including the
parts they made. I wonder why their attitude changed here though?
Especially on a cap that is large enough that plenty of info can be
printed on it?

In my first post, I was being facetious about the espionage part, and
what I figured was it had something to do with private branding. The
way it is, one could buy an unmarked cap in a marked box and resell
it either as the brand name on the box, or as one by the sellers
company just by sending it less the box. They all should have a code
or stamp somewhere to tell where they came from, but knowing how
Matsushita used to be, private branding was the only conclusion I
could think of. At the time, Matsushita manufactured virtually every
part in their TV sets and VCRs. It sounded to me that the last batch
Rich had bought had the brand name printed right on it.

Best,

Will



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

In the post-ISO-9000 world, where trackability is everything,
manufacturers' data sheets always include a specification on how the
component is marked. Given the exact Panasonic/Matsushita part
number, a visit to the Pana/Matsu website will dredge up the data
sheet which will provide a precise answer.

Since my nominal retirement, I consulted rather a lot with various
manufacturers, and as a point of fact, this is a matter that is
validated upon incoming inspection for all parts. A comparison of

the

components is made to the data sheet, and if the markings do not

match

what the data sheet claims, then the lot is initially rejected, for
later review. Generally, it results in a phone call to the vendor,

a

corrective action request, and a fair amount of expensive

paperwork.

No parts are changed, but the vendor now knows that if they're going
to ship parts that do not conform to the data sheet, including
markings, then they notify the customer in advance that what they're
about to receive is going to be marked differently....Z

--- In ham_amplifiers@..., "hbmandel" <ka1xo@> wrote:

Look for the Matsushita logo, which is a triangle with arrow

points

at the apex of each corner.

They might have a three letter code or a four letter code
like MSC, MECA, etc. The "(M)" says it all, by the way.

There are billions and billions of Masushita components out there
with very obscure markings.

Hal Mandel




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

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

wrote:

- We recently purchased a lot of 200, 560uF, 450v, 105?C

Matsushita-

Panasonic HV electrolytic capacitors from Digikey. The boxes

they

came in say Panasonic but the capacitors therein state only

the

ratings and "6072C6(M)", but there's no named mfg. What's up

with

that?

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

I got an e-mail from the unknown admin
chastizing me over questioning Tom and what they called other
published engineers.

### so what exactly did Tom publish..... besides Ameritron manuals?

### They had this silly roaring discussion on 'AMPS' 2 weeks
ago.... the poor fellow asking the question gets chastised by a guy
in 9 land ... "Tom rauch already gave u the answer... just ignore
the other 24 reply's" So I guess if u post on AMPS... the only
valid reply is Tom.

### another fellow I know.. Ken W2DTC wanted to know how much
anode diss is required for a 1500 W pep output linear... running
class A... on AM. They went off on a tangent.. and then some.
Correct answer of course is just 1500/.25 = 6 kw pep input.
PEP Anode diss is of course.. 6000-1500 = 4500 w. Keyed..
with NO modulation... it becomes 6000-300/375 = 5700/5625 w...
CCS diss. A single 3x3 won't do it either. A pair of em
will.. or a single 3x6... or something bigger still. Slick way
to justify a big tube in the shack imo. I emailed Ken... he
agreed... I had nailed it.

### Rauch never did get that one right... neither did the secret
admin.... nor anyone else.



When this didn't work with me, he went so low as to try and

question my education. When I told him what to do with his

question, the admin privately e-mailed me the chastizing e-mail.

### Maybe some of these guys with fancy degrees..... should ask
for their money back ! IMO, designing and building a linear is
nothing more than a high school science project.... not rocket
science. It's all old news. Some of the implementation
techiniques used these days are sorta new.... for hams.

As Paul Harvey said, "... and now you know [pause] the Rest of the
Story."

#### This grp is up to 180 now... and climbing daily.

Later... Jim VE7RF

Best,

Will

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

### A few good spikes down the power line and the diodes WILL
fail..

RICH SEZ...Only if the amplifier is on at the time and only if the

spike goes above 451 volts-pk. And, it hasn't happened in 20+
years.

..esp with only 33% more PIV....and little or no additional
protection.

RICH SEZ... No "protection" whatsoever because now I understand why.

### little or no additional protection means no big momma MOV's
on the 240 V line... NOT no hv fuses, glitch R, safety diodes,
etc.... and those devices are NOT gonna save ur diode stack from
a big spike coming in off the street. Spikes will pass through a
plate xfmr... like it wasn't there.

### with a safety factor of only 33%.... the diodes would fry...
LONG before any MOV cliped the spikes off.

RICH SEZ...K5JV told me that he experienced a lightning strike

that blew two bolt'em-in MOVs clean out of the box and left them
smoking on the deck.

### Not big enough then! Where was the lightning hit... across
the street... onto the 14.4 kv line iteself or what ?

### For real protection... the 4" square x 1" thick MOV's should
be used... in a sub box..right at ur main 200 A panel... wired
each line to neutral. That's the 1st layer of protection.

Then.... install the bolt down MOV's at the plate xfmr pri
input.... both across the 240 line... and each side to
neutral/grnd. That's the 2nd layer of protection... ditto with
any power bars, etc for xcvr's, other gear.

...

RICH SEZ....You seem to assume that conduction for a 250v

rating begins at 251 x 1.14 volts. It does not.

### I already know that. Rich..... take a 0-277 v variac..... and
a 250 V rated MOV..... and apply >250 V on it for 1 hr...then
tell us what happens !

RICH SEZ... According to Panasonic spec, one their 250vac-rated MOVs
begins to conduct current at 390v +/- 10%. This is 278v-rms +/-
10%.


### Each Manufacturer of MOV's rates em a dif way. Some will rate
by joules... some by max peak current.. some both. Rise times will
vary... some will respond in 80 nanoseconds.. some 20.. some just
1 nano second. Some will take XXX peak amps.... for a specified
duration.... the duration will also vary, etc. Point here is...
don't take one type of Panasonic MOV... and use those specs.. and
apply to all other MOV's... doesn't work.

.....
### The whole point here is... with successive hits... the V

rating

of any MOV starts to drop... another reason we fuse em.

RICH SEZ...Agreed

### Most newer homes in Florida have giant MOV's located just

below the main 200 A service panel... connected to main Buss... via
a 20-60A breaker.

### I'm sure this is a house insurance co requirement in some
counties now. Insurance co's get tired of paying out for blown up
fridges, TV's... and everything else in your home... every time a
lightning storm happens... which is all the time in Florida...
lightning capital of the world.

### Rich... you hook ur stuff up any way you want. Me... I play

it safe. I have seen way too much damage done in the last 30 yrs, to

come home and then wire stuff up mickey mouse style. Diodes are
cheap, MOV's are cheap. Correct V sized MOV's are just as cheap

as incorrectly sized MOV's. Fast fuses are just as cheap as slow

ones. Glitch R's are cheap...

RICH SEZ... Not for an 8171.

### 2 x 100 ohm 225 W wire wounds in parallel ARE cheap.[abt
[$13.00 each from mouser] If that doesn't do the trick [works
good with 8 kv and 135 uf filter]... then 4 x 200 ohm, 225 w
ww's in parallel will]. Also 4 x 200 ohm, 12" long x 1" diam
surplus globars type CX will also work. The CX types.. built
in the 60's were meant to be air cooled... they are NOT glass
bodied... and can't be put in oil... perfect for glitch service.
They are available surplus. Running an 8171 with NO 50 ohm
glitch is silly... and dangerous. Get off the.... "get cheap
program"

later...... Jim VE7RF

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

In the post-ISO-9000 world, where trackability is everything,
manufacturers' data sheets always include a specification on how the
component is marked. Given the exact Panasonic/Matsushita part
number, a visit to the Pana/Matsu website will dredge up the data
sheet which will provide a precise answer.

Since my nominal retirement, I consulted rather a lot with various
manufacturers, and as a point of fact, this is a matter that is
validated upon incoming inspection for all parts. A comparison of the
components is made to the data sheet, and if the markings do not match
what the data sheet claims, then the lot is initially rejected, for
later review. Generally, it results in a phone call to the vendor, a
corrective action request, and a fair amount of expensive paperwork.
No parts are changed, but the vendor now knows that if they're going
to ship parts that do not conform to the data sheet, including
markings, then they notify the customer in advance that what they're
about to receive is going to be marked differently....Z

On Nov 21, 2006, at 10:16 AM, zerobeat40 wrote:

The first question is why would you expect the manufacturer's name to
be on the part? Does the data sheet tell you it's there?

Where is the data sheet?

Digi-Key stocks several parts matching that description. If you want
an exact answer, you need to supply us with the Digi-Key part number.

P11691

However, I can venture a reply....since components began getting
smaller, roughly in 1940, manufacturers have had to grapple with how
to place markings on a component with less space available. Logos
became commonplace. Today, with the standard electronic component
being 60 X 30 mils, the official mark for a manufacturer may be
nothing more than a dot of a specific color.

These caps are 51mm x 63mm.

In looking at the manufacturer's data sheet for Digi-Key's part number
P10680-ND (One of the several digi-key part numbers that matches your
description), it becomes obvious that the manufacturer's chosen logo
is a capital letter M in a box with rounded corners.

In case you have not actually read the data sheet, here it is:

I found P11691 with: dksus.dll?KeywordSearch

The process of engineering is to predict - create an expectation -
then measure reality and compare to the expectation, and carefully
understand why they differ, and adjust either the prediction or the
measurement process. In this case, you made a measurement (visual
inspection of the capacitor), but failed to indicate how you arrived
at your prediction

Predict? I purchased 200 of p/n P11691, and those were the specs in the Digikey catalog.

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

On Nov 21, 2006, at 10:30 AM, Robert B. Bonner wrote:

The place I worked in college was also a huge Panasonic cap dealer.

The Panasonic caps are usually the blue ones. They make caps for quite a
number of electronic manufacturers. End up in everything.

An educated guess is Digikey received a manufacturers' overrun...

These are a normally stocked item. ...


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

On Nov 21, 2006, at 9:13 AM, hbmandel wrote:

Look for the Matsushita logo, which is a triangle with arrow points
at the apex of each corner.

They might have a three letter code or a four letter code
like MSC, MECA, etc. The "(M)" says it all, by the way.

thanx, Hal

There are billions and billions of Masushita components out there
with very obscure markings.

Hal Mandel

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

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

- We recently purchased a lot of 200, 560uF, 450v, 105?C

Matsushita-

Panasonic HV electrolytic capacitors from Digikey. The boxes

they

came in say Panasonic but the capacitors therein state only the
ratings and "6072C6(M)", but there's no named mfg. What's up

with

that?

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