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Re: Tank eff......WAS 3 - phase HV supply

PA3DUV
 

开云体育

Peter,
?
The 200 C was the coil wire, not the toroid itself.
The toroid?barely heated up.
?
Cheers, Dick
PA3DUV
?

----- Original Message -----
Sent: Friday, October 06, 2006 12:21 AM
Subject: RE: [ham_amplifiers] Re: Tank eff......WAS 3 - phase HV supply


Hi Dick,

200° on a iron powder toroid is pretty high.
That will raise your circuit L at least by 4%.
I replaced many low band toroidsin Command amps...

I wonder what the temperature of your 10m coil is at that 6KW

73
Peter

________________________________

From: ham_amplifiers@yahoogroups.com [mailto:ham_amplifiers@yahoogroups.com]
On Behalf Of PA3DUV

The hottest point was the coil section INSIDE the toroid, 200C + was
measured

The 10-20-30 meter tank coil section went up to 130C
Re: Tank eff......WAS 3 - phase HV supply

Peter Voelpel
 

________________________________

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

Very true, in high impedance output networks you are obliged to
run high Q
as the minum plate C is too high for >lower Q
I guess the 5/32" coil is at the cathode?
#### Either insert .6 uh b4 the main PI-NET [or pi-L] or
just tap into the .6uh point... with the vac tune cap. Then..
u can transform the plate load Z DOWN to something lower...

it does not help much if you need to transform down from 3kohms
## Myself and others... bitched to Eimac about the Class B
nonsense in all of Eimac's older literature... it finally got
corrected..... GG linears.... drawing as little as 1 ma... are
actually AB-2.

AB2 only works with modern high mu tubes, to get gain from older tubes you
needed class B

### I concur with everything else though. I posdted a few more
pix as well.

very nice!
I also prefer the old style meters
73
Peter
Re: Hi-pot tester

craxd
 

Old coils that ran off points could have a frequency thats
derived from a RPM of 800 to 2000+ RPM or so. The new ones
without points use a pulse from a toothed rotating magnets
and a hall effect sensor to fire a power switching transistor,
but still use the RPM of the engine to turn the magnets. The
RPM is multiplied by the number of cylinders to obtain the
frequency of the coil. A 4 cyl. engine idling at 800 RPM would
have a coil frequency of 3200 Hz. So it's according to what
the engines RPM is. The lowest frequency is what you design around
as anything higher, the flux density actually drops. It's
also according to the material of the core. Some iron (silicon
steel), according to the type and thickness, can be ran up to 10
kHz according to the steel manufacturers. However, lets take a
4 cyl at 2000 RPM, that would be a frequency of 8 kHz. An 8 cyl
engine would be 16 kHz at 2000 RPM. The thing is, a motors RPM
can be revved on up, so the frequency can vary even higher. Some
of the new coils have an EI core shape, but to my opinion,
they're ferrite like a TV's flyback transformer. You can't really
see what it is as they're enclosed in plastic. Anyhow, this can
give you an idea of what the operating frequency is for the coil.

Best,

Will


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

Hi,Guillermo,
I think your square wave generator's freqence is too high?the
ignition automotive coils's is iron not ferrite, the frequence
must below kilo hertz
73! Hsu


u may be in the good direction; I did not tried with TV flyback
transformers, but did once some experiments with old ignition
automotive
coils, excited with a square wave generator and a darlington
transistor
amplifier. I could never get more than 400 volts pk-pk. With 13.8V
supply.
The circuit was not optimized also due to lack of time for another
tasks, but
I think one could get better results.
More experimentation is in order here.

Best regards
Guillermo - LU8EYW.

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Re: Help - Need Alpha 99 PS/xfmr info - revisited

KR4DA
 

开云体育

NO responces.. I didn't respond earlier cause I was going to tell you
to CALL ALPHA. Email them too.. I have had responces to my questions from them..
But I thought you might not like that responce...I have a 91b I believe it's the same.
If you perfer and don't want to call ALPHA
I will get the manual out and look it up.
Call me 904-282-6896

de KR4DA Bob


Tony King - W4ZT wrote:

Hi Group,

I am still looking for the schematic and hookup info for the Alpha 99 HV
transformer. If you have that information that you would be willing to
share, please contact me. There were exactly ZERO responses to my last
request.

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


-- 
Bob
Vmoa chat list -> 
Vmoa tech list home -> 


Middleburg Fl (South Jacksonville)
ICQ 13912841
Web Page 

Visit the FDXPG at  

Ham Radio Calls: KR4DA FG/KR4DA J79DA HK0/KR4DA

Motorcycles CBMMA #4
1977 XS750D 1J7008405
1997 Vmax12J VMOA #504

Re: Tank eff......WAS 3 - phase HV supply

pentalab
 

--- In ham_amplifiers@..., "Peter Voelpel" <df3kv@...>
wrote:
one reason I use bigger material for the coils and strips
0,5" tubing for 50A RF current, 0,75" flat strip for the same
current. 1" tubing for 100A or 1,5" flat copper strips
if I am space limited I blow air through smaller tubing
#### partially agreed. There is no way .5" tubing is going to
handle 50 A.... maybe 36 A. Depends whether RTTY/SSB... and
also what Freq. Skin depth at 1.8 mhz = .05mm Skin depth at
30 mhz = .01 mm ....... a 5:1 ratio !

### 3 A of plate curent x Q of 10 is gonna result in aprx 30-
36 A of circulating current in the pi-net.

### 1.5+ " wide flat strap is easy to wind for 10m... than
1" tubing coil. 3/4" tubing is about the upper limit for
practical tubing winding....esp with an aprx 3" ID for 10m.


### with too high a Q on a tuned input... we could actually get
the 5/32 " solid copper 4uh coil good and warm on the high
bands 20-17-15m.

Very true, in high impedance output networks you are obliged to
run high Q
as the minum plate C is too high for >lower Q
I guess the 5/32" coil is at the cathode?

#### Either insert .6 uh b4 the main PI-NET [or pi-L] or
just tap into the .6uh point... with the vac tune cap. Then..
u can transform the plate load Z DOWN to something lower... the
PI/PI-L can handle. Yes, the 5/32" solid CU coil IS the 4.0
uh tuned input coil.



### I'd say we may well be arguing semantics here.... but I'd
say it's just one more advantage of GG amps.... better apparent
eff... and slightly lower plate diss.

No, not in the same class of operation, like AB1 in GC and AB2 in
GG.
Unless you are running class B in the GG amp and AB1 in grounded
cathode
when you compare efficiency, it will be >the same.
Efficiency is much higher in class B
### Class B in any GG amp is NOT linear. Class B implies a
180 deg conduction angle.... IE bias set so idle current is
exactly zero ma..... which would result in lousy TX imd.

### A SB-220.. with a 5.0 v zener for bias, has a 210 deg
conduction angle idles at, I think 180 ma.

## Myself and others... bitched to Eimac about the Class B
nonsense in all of Eimac's older literature... it finally got
corrected..... GG linears.... drawing as little as 1 ma... are
actually AB-2.

### I concur with everything else though. I posdted a few more
pix as well.

later... Jim VE7RF
73
Peter
Re: Tank eff......WAS 3 - phase HV supply

FRANCIS CARCIA
 

Danger that toroid must be getting to the curie temperature not a good thing when it changes forever..gfz

GGLL wrote:

PA3DUV escribi:
> > ## A few months back.... I bought a Fluke "Mini 62" IR point and
> > shoot thermonter.... comes with a built in laser pointer.... and can
> > be switched from C to F as well. Works slick.... and will
> > give instant readings onto one LCD display
>
> 2 weeks ago I checked out my twin GU84B tetrode amp with that.
>
> Running 6 kW on 7 MHz into the R&S dummyload I found the following hot
> spots:
>
> The connection between tubular wound 20 meter coil and the lead to the
> toroidal 40/80/160 meter coil

How are these connections made?. Mechanically wrapped and then soldered?,
with maybe siver solder?.

Best regards
Guillermo - LU8EYW.

P.S.: curious to know how one do at those power levels.
>
> The coil section on the INSIDE of the toroid
>
> The connection from the coil to the bandswitch
>
> The hottest point was the coil section INSIDE the toroid, 200C + was
> measured
>
> The DC blocking caps (2 in parallel) remained remarkable cool, no
> significabt temperature rise.
>
> The anode coolers went up to 95C
>
> The 10-20-30 meter tank coil section went up to 130C
>
> I'll post some pictures of the actual measurement when I'm back home.
>
> Cheers from YMM, Alberta,
> Dick, PA3DUV
>
>
>
>
> ----- Original Message -----
> *From:* pentalab jim.thomson@telus.com>
> *To:* ham_amplifiers@yahoogroups.com
> ham_amplifiers@yahoogroups.com>
> *Sent:* Thursday, October 05, 2006 10:45 PM
> *Subject:* [ham_amplifiers] Re: Tank eff......WAS 3 - phase HV supply
>
> --- In ham_amplifiers@yahoogroups.com
> ham_amplifiers@yahoogroups.com>, "PA3DUV" wrote:
> >
> > Hey guys,
> >
> > don't make a fuss about the last killowatt :-))))))))))))))))
> >
> > Cheers, Dick
> > PA3DUV
> >
> >
> > ----- Original Message -----
> > From: Peter Voelpel
> > To: ham_amplifiers@yahoogroups.com
> ham_amplifiers@yahoogroups.com>
> > Sent: Wednesday, October 04, 2006 10:29 PM
> > Subject: RE: [ham_amplifiers] Re: 3 - phase HV supply
> >
> >
> > Sorry,
> >
> >
> > Indeed, for 25KW out one needs 45KVA, but only in class B.
> > 67% efficiency is a bit high in class AB, it will be around 63%
> minus loss in the pi-network.
> > Some of the output in a GG amp is coming from the driver, so
> efficiency is NOT= output*100%/input power...
>
> ### How come all the tetrode fellows always say that ?? We
> carefully measured the eff on this latest 6000A7 linear... and
> got 67%. Now granted... the wattmeter slug could be a little
> high... the plate current + HV meter's could be a little low...
> skewing the results.
>
> ### Figure maybe 1% loss in the tank circuit... from the coil.
> And more like almost 2% on 10m.[ 1-2% of the power output]
> The kicker is.... on 10m...all that tank coil heat is being dumped
> into just 2 x turns..... vs less heat being dumped into the
> ENTIRE coil (or a portion of it)... on the lower bands.
>
> ### In various tests I have done... one would think that on say a
> 20-10m coil.... that when on say 15m.... that the adjacent
> unused portion of the coil would heatsink the used portion......
> it sorta does... poorly. It ends up the used portion will get
> hot... the unused portion [next turn over] runs barely warm... go
> figure.
>
> ### BTW.... most Vac caps have an unloaded Q of around 5000....
> compared to a typ tank coil of 100-300. IMO... most of the tank
> losses are going to be in the tank coil... interconnecting
> straps.... bandswitch contacts, etc.
>
> ### You need very very few watts to heat up a tank coil....esp
> hollow tubing. With solid material... like say 8 ga wire
> [used on the L4B 2 x 3-500Z] used on 80/40m.. or say solid 6
> ga wire used on some 20m coils.... it just takes longer to heat
> up..... the flipside is... with any solid material.... it takes a
> helluva lot longer to cool down.... cuz of the the stored up heat
> inside a bigger thermal mass.
>
> ### On a related subject.... if I remember correctly, in
> Eimac's .. "care and feeding" for thermal properties... copper
> was ... '1.0' and aluminium was '.57' IE: aluminium
> doesn't conduct heat worth banana's... compared to copper !
> Steel, and stainless steel is a LOT worse......... just
> something to keep in mind.
>
> ## A few months back.... I bought a Fluke "Mini 62" IR point and
> shoot thermonter.... comes with a built in laser pointer.... and can
> be switched from C to F as well. Works slick.... and will
> give instant readings onto one LCD display ... and a 2nd
> display will always hold the peak highest temp. [both backlit to
> boot] By holding the trigger down solid... and moving the
> laser pointer about slowly... or quickly.... you can find hot
> spots all over the place ! You can see quickly where you are
> leaking heat from the outside of a home.... measure exhaust
> manifold temps, xfmr's... tank coils... find where ur attic is
> not insulated properly [heat radiating down from a ceiling... in
> just one spot], and doz's of other uses..... like measuring
> exhaust air temp from a linear... Air conditioning problems in the
> home or car. This Fluke 62 goes from below freezing
> [instant temp readings of ur fridge/deep freezer] to something
> like 900 deg F. It will easily differentiate between one part of
> a tank coil.... and another portion... just a few mm away. A
> great bargain for around $100.00 Shop around.
>
> ### IMO.... since a huge portion of the drive power on a GG linear
> [ in this case, 640w of the 800 w of drive used] appears in the
> output.... I'd consider that ... "free extra eff".
>
> ### In any event... anode dissipation is REDUCED... if apparent
> eff is UP.
>
> ## DC plate input - power out = anode diss. What am I
> supposed to do.... subtract the drive power... from the power
> output 1st.... THEN calculate plate diss ??? Nobody is about
> to do that.... so why bother subtracting the drive power from the
> output, to cal eff ?
>
> ### I tried several experiments by varying the loaded tank Q on
> various bands... and also varying the loaded tank Q on the tuned
> input network. Now Rauch will tell you tank Q makes no diff..
> and is not important.... and a loaded Q of "22" is just fine.....
> fact is loaded Q on a tank circuit DOES make a big
> difference. A loaded Q of around 3.3 for a tuned input is fine
> [this would equate to Q =2 doing it Rich's way]. A loaded Q
> of 10-12 [new method] [ 8-10 old method] is ample for the high
> power PI output. You start running a Q of 12-22 [new
> method].... you can easily see, and measure effects asap. The
> circulating currents skyrocket... tank coils + bandswitch / roller
> inductor conacts heat up.... eff DROPS, amp tuning becomes narrow
> banded... requiring more frequent tune ups, when u qsy etc.
>
> ### On a tuned input.... I tried a Q of 5.... eff drops..esp on
> the higher bands. We used bird line sections on both the
> input/output of the tuned input circuit [consisted of 2 x
> broadcast variables + a tapped 4 uh coilt] output through the 2nd
> line section... then into a 50 ohm load was 150-160w . By
> INcreasing the small coil's uh tap... just a tiny bit.....
> lowering the Q.... and power out of the tuned input... shot up to
> 195 w.
>
> ### with too high a Q on a tuned input... we could actually get
> the 5/32 " solid copper 4uh coil good and warm on the high
> bands 20-17-15m.
>
> ### IF the tuned input is NOT done correctly..... it will kill
> ur eff.. real fast. Locating the C2 tuned input variable cap
> closer to the tube socket/ and/or installing a small 100 pf NPO
> doorknob next to the socket..[ in effect moving a portion of C2
> closer to the socket] will improve the eff on the higher bands.
>
> ### I'd say we may well be arguing semantics here.... but I'd
> say it's just one more advantage of GG amps.... better apparent
> eff... and slightly lower plate diss.
>
> Later... Jim VE7RF
>
> > 73
> > Peter
> >
>
>

Re: Tank eff......WAS 3 - phase HV supply

GGLL
 

PA3DUV escribi:
> ## A few months back.... I bought a Fluke "Mini 62" IR point and
> shoot thermonter.... comes with a built in laser pointer.... and can
> be switched from C to F as well. Works slick.... and will give instant readings onto one LCD display
2 weeks ago I checked out my twin GU84B tetrode amp with that.
Running 6 kW on 7 MHz into the R&S dummyload I found the following hot spots:
The connection between tubular wound 20 meter coil and the lead to the toroidal 40/80/160 meter coil
How are these connections made?. Mechanically wrapped and then soldered?, with maybe siver solder?.

Best regards
Guillermo - LU8EYW.

P.S.: curious to know how one do at those power levels.
The coil section on the INSIDE of the toroid
The connection from the coil to the bandswitch
The hottest point was the coil section INSIDE the toroid, 200C + was measured
The DC blocking caps (2 in parallel) remained remarkable cool, no significabt temperature rise.
The anode coolers went up to 95C
The 10-20-30 meter tank coil section went up to 130C
I'll post some pictures of the actual measurement when I'm back home.
Cheers from YMM, Alberta,
Dick, PA3DUV
----- Original Message -----
*From:* pentalab <mailto:jim.thomson@...>
*To:* ham_amplifiers@...
<mailto:ham_amplifiers@...>
*Sent:* Thursday, October 05, 2006 10:45 PM
*Subject:* [ham_amplifiers] Re: Tank eff......WAS 3 - phase HV supply
--- In ham_amplifiers@...
<mailto:ham_amplifiers@...>, "PA3DUV" <pa3duv@...> wrote:
>
> Hey guys,
>
> don't make a fuss about the last killowatt :-))))))))))))))))
>
> Cheers, Dick
> PA3DUV
>
>
> ----- Original Message -----
> From: Peter Voelpel
> To: ham_amplifiers@...
<mailto:ham_amplifiers@...>
> Sent: Wednesday, October 04, 2006 10:29 PM
> Subject: RE: [ham_amplifiers] Re: 3 - phase HV supply
>
>
> Sorry,
>
>
> Indeed, for 25KW out one needs 45KVA, but only in class B.
> 67% efficiency is a bit high in class AB, it will be around 63%
minus loss in the pi-network.
> Some of the output in a GG amp is coming from the driver, so
efficiency is NOT= output*100%/input power...
### How come all the tetrode fellows always say that ?? We
carefully measured the eff on this latest 6000A7 linear... and
got 67%. Now granted... the wattmeter slug could be a little
high... the plate current + HV meter's could be a little low...
skewing the results.
### Figure maybe 1% loss in the tank circuit... from the coil.
And more like almost 2% on 10m.[ 1-2% of the power output]
The kicker is.... on 10m...all that tank coil heat is being dumped
into just 2 x turns..... vs less heat being dumped into the
ENTIRE coil (or a portion of it)... on the lower bands.
### In various tests I have done... one would think that on say a
20-10m coil.... that when on say 15m.... that the adjacent
unused portion of the coil would heatsink the used portion......
it sorta does... poorly. It ends up the used portion will get
hot... the unused portion [next turn over] runs barely warm... go
figure.
### BTW.... most Vac caps have an unloaded Q of around 5000....
compared to a typ tank coil of 100-300. IMO... most of the tank
losses are going to be in the tank coil... interconnecting
straps.... bandswitch contacts, etc.
### You need very very few watts to heat up a tank coil....esp
hollow tubing. With solid material... like say 8 ga wire
[used on the L4B 2 x 3-500Z] used on 80/40m.. or say solid 6
ga wire used on some 20m coils.... it just takes longer to heat
up..... the flipside is... with any solid material.... it takes a
helluva lot longer to cool down.... cuz of the the stored up heat
inside a bigger thermal mass.
### On a related subject.... if I remember correctly, in
Eimac's .. "care and feeding" for thermal properties... copper
was ... '1.0' and aluminium was '.57' IE: aluminium
doesn't conduct heat worth banana's... compared to copper !
Steel, and stainless steel is a LOT worse......... just
something to keep in mind.
## A few months back.... I bought a Fluke "Mini 62" IR point and
shoot thermonter.... comes with a built in laser pointer.... and can
be switched from C to F as well. Works slick.... and will
give instant readings onto one LCD display ... and a 2nd
display will always hold the peak highest temp. [both backlit to
boot] By holding the trigger down solid... and moving the
laser pointer about slowly... or quickly.... you can find hot
spots all over the place ! You can see quickly where you are
leaking heat from the outside of a home.... measure exhaust
manifold temps, xfmr's... tank coils... find where ur attic is
not insulated properly [heat radiating down from a ceiling... in
just one spot], and doz's of other uses..... like measuring
exhaust air temp from a linear... Air conditioning problems in the
home or car. This Fluke 62 goes from below freezing
[instant temp readings of ur fridge/deep freezer] to something
like 900 deg F. It will easily differentiate between one part of
a tank coil.... and another portion... just a few mm away. A
great bargain for around $100.00 Shop around.
### IMO.... since a huge portion of the drive power on a GG linear
[ in this case, 640w of the 800 w of drive used] appears in the
output.... I'd consider that ... "free extra eff".
### In any event... anode dissipation is REDUCED... if apparent
eff is UP.
## DC plate input - power out = anode diss. What am I
supposed to do.... subtract the drive power... from the power
output 1st.... THEN calculate plate diss ??? Nobody is about
to do that.... so why bother subtracting the drive power from the
output, to cal eff ?
### I tried several experiments by varying the loaded tank Q on
various bands... and also varying the loaded tank Q on the tuned
input network. Now Rauch will tell you tank Q makes no diff..
and is not important.... and a loaded Q of "22" is just fine.....
fact is loaded Q on a tank circuit DOES make a big
difference. A loaded Q of around 3.3 for a tuned input is fine
[this would equate to Q =2 doing it Rich's way]. A loaded Q
of 10-12 [new method] [ 8-10 old method] is ample for the high
power PI output. You start running a Q of 12-22 [new
method].... you can easily see, and measure effects asap. The
circulating currents skyrocket... tank coils + bandswitch / roller
inductor conacts heat up.... eff DROPS, amp tuning becomes narrow
banded... requiring more frequent tune ups, when u qsy etc.
### On a tuned input.... I tried a Q of 5.... eff drops..esp on
the higher bands. We used bird line sections on both the
input/output of the tuned input circuit [consisted of 2 x
broadcast variables + a tapped 4 uh coilt] output through the 2nd
line section... then into a 50 ohm load was 150-160w . By
INcreasing the small coil's uh tap... just a tiny bit.....
lowering the Q.... and power out of the tuned input... shot up to
195 w.
### with too high a Q on a tuned input... we could actually get
the 5/32 " solid copper 4uh coil good and warm on the high
bands 20-17-15m.
### IF the tuned input is NOT done correctly..... it will kill
ur eff.. real fast. Locating the C2 tuned input variable cap
closer to the tube socket/ and/or installing a small 100 pf NPO
doorknob next to the socket..[ in effect moving a portion of C2
closer to the socket] will improve the eff on the higher bands.
### I'd say we may well be arguing semantics here.... but I'd
say it's just one more advantage of GG amps.... better apparent
eff... and slightly lower plate diss.
Later... Jim VE7RF

> 73
> Peter
>
Re: Tank eff......WAS 3 - phase HV supply

Peter Voelpel
 

Hi Dick,

200° on a iron powder toroid is pretty high.
That will raise your circuit L at least by 4%.
I replaced many low band toroidsin Command amps...

I wonder what the temperature of your 10m coil is at that 6KW

73
Peter

________________________________

From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of PA3DUV

The hottest point was the coil section INSIDE the toroid, 200C + was
measured

The 10-20-30 meter tank coil section went up to 130C
Re: Tank eff......WAS 3 - phase HV supply

Peter Voelpel
 

________________________________

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

Some of the output in a GG amp is coming from the driver, so
efficiency is NOT= output*100%/input power...

### How come all the tetrode fellows always say that ?? We
carefully measured the eff on this latest 6000A7 linear... and
got 67%. Now granted... the wattmeter slug could be a little
high... the plate current + HV meter's could be a little low...
skewing the results.

lets assume you drive the 3CX6000 with 1KW.
63% of this drive power is on the output.
the driving power is from a different power supply.
when you calculate efficieny you have to deduct 630W from what is shown on
your wattmeter


### Figure maybe 1% loss in the tank circuit... from the coil.
And more like almost 2% on 10m.[ 1-2% of the power output]
The kicker is.... on 10m...all that tank coil heat is being dumped
into just 2 x turns..... vs less heat being dumped into the
ENTIRE coil (or a portion of it)... on the lower bands.

### In various tests I have done... one would think that on say a
20-10m coil.... that when on say 15m.... that the adjacent
unused portion of the coil would heatsink the used portion......
it sorta does... poorly. It ends up the used portion will get
hot... the unused portion [next turn over] runs barely warm... go
figure.

shure, it must be
there is no rf current flowing in the unused part
### You need very very few watts to heat up a tank coil....esp
hollow tubing. With solid material... like say 8 ga wire
[used on the L4B 2 x 3-500Z] used on 80/40m.. or say solid 6
ga wire used on some 20m coils.... it just takes longer to heat
up..... the flipside is... with any solid material.... it takes a
helluva lot longer to cool down.... cuz of the the stored up heat
inside a bigger thermal mass.

one reason I use bigger material for the coils and strips
0,5" tubing for 50A RF current, 0,75" flat strip for the same current.
1" tubing for 100A or 1,5" flat copper strips
if I am space limited I blow air through smaller tubing
### IMO.... since a huge portion of the drive power on a GG linear
[ in this case, 640w of the 800 w of drive used] appears in the
output.... I'd consider that ... "free extra eff".

Not really, you have to pay the bill for it...
### In any event... anode dissipation is REDUCED... if apparent
eff is UP.

No, that part of the efficiency is dissipated in the driver
## DC plate input - power out = anode diss. What am I
supposed to do.... subtract the drive power... from the power
output 1st.... THEN calculate plate diss ??? Nobody is about
to do that.... so why bother subtracting the drive power from the
output, to cal eff ?

not to cheat yourself

### with too high a Q on a tuned input... we could actually get
the 5/32 " solid copper 4uh coil good and warm on the high
bands 20-17-15m.

Very true, in high impedance output networks you are obliged to run high Q
as the minum plate C is too high for >lower Q
I guess the 5/32" coil is at the cathode?
### IF the tuned input is NOT done correctly..... it will kill
ur eff.. real fast. Locating the C2 tuned input variable cap
closer to the tube socket/ and/or installing a small 100 pf NPO
doorknob next to the socket..[ in effect moving a portion of C2
closer to the socket] will improve the eff on the higher bands.

yes, you must avoid long leads there
### I'd say we may well be arguing semantics here.... but I'd
say it's just one more advantage of GG amps.... better apparent
eff... and slightly lower plate diss.

No, not in the same class of operation, like AB1 in GC and AB2 in GG.
Unless you are running class B in the GG amp and AB1 in grounded cathode
when you compare efficiency, it will be >the same.
Efficiency is much higher in class B
73
Peter
Re: Tank eff......WAS 3 - phase HV supply

PA3DUV
 

开云体育

> ## A few months back.... I? bought a Fluke? "Mini 62"?? IR point and
> shoot thermonter.... comes with a built in laser pointer.... and can
> be? switched? from C? to F as well.??? Works slick.... and will?
> give? instant readings onto? one LCD? display
?
2 weeks ago I checked out? my twin GU84B tetrode amp with that.
?
Running 6 kW on 7 MHz into the R&S dummyload I found the following hot spots:
?
The connection between tubular wound 20 meter coil and the lead to the toroidal 40/80/160 meter coil
?
The coil section on the INSIDE of the toroid
?
The connection from the coil to the bandswitch
?
The hottest point was the coil section INSIDE the toroid, 200C + was measured
?
The DC blocking caps (2 in parallel) remained remarkable cool, no significabt temperature rise.
?
The anode coolers went up to 95C
?
The 10-20-30 meter tank coil section went up to 130C
?
I'll post some pictures of the actual measurement when I'm back home.
?
Cheers from YMM, Alberta,
Dick, PA3DUV
?
?
?

----- Original Message -----
From: pentalab
Sent: Thursday, October 05, 2006 10:45 PM
Subject: [ham_amplifiers] Re: Tank eff......WAS 3 - phase HV supply

--- In ham_amplifiers@yahoogroups.com, "PA3DUV" wrote:
>
> Hey guys,
>
> don't make a fuss about the last killowatt :-))))))))))))))))
>
> Cheers, Dick
> PA3DUV
>
>
> ----- Original Message -----
> From: Peter Voelpel
> To: ham_amplifiers@yahoogroups.com
> Sent: Wednesday, October 04, 2006 10:29 PM
> Subject: RE: [ham_amplifiers] Re: 3 - phase HV supply
>
>
> Sorry,
>
>
> Indeed, for 25KW out one needs 45KVA, but only in class B.
> 67% efficiency is a bit high in class AB, it will be around 63%
minus loss in the pi-network.
> Some of the output in a GG amp is coming from the driver, so
efficiency is NOT= output*100%/input power...

### How come all the tetrode fellows always say that ?? We
carefully measured the eff on this latest 6000A7 linear... and
got 67%. Now granted... the wattmeter slug could be a little
high... the plate current + HV meter's could be a little low...
skewing the results.

### Figure maybe 1% loss in the tank circuit... from the coil.
And more like almost 2% on 10m.[ 1-2% of the power output]
The kicker is.... on 10m...all that tank coil heat is being dumped
into just 2 x turns..... vs less heat being dumped into the
ENTIRE coil (or a portion of it)... on the lower bands.

### In various tests I have done... one would think that on say a
20-10m coil.... that when on say 15m.... that the adjacent
unused portion of the coil would heatsink the used portion......
it sorta does... poorly. It ends up the used portion will get
hot... the unused portion [next turn over] runs barely warm... go
figure.

### BTW.... most Vac caps have an unloaded Q of around 5000....
compared to a typ tank coil of 100-300. IMO... most of the tank
losses are going to be in the tank coil... interconnecting
straps.... bandswitch contacts, etc.

### You need very very few watts to heat up a tank coil....esp
hollow tubing. With solid material... like say 8 ga wire
[used on the L4B 2 x 3-500Z] used on 80/40m.. or say solid 6
ga wire used on some 20m coils.... it just takes longer to heat
up..... the flipside is... with any solid material.... it takes a
helluva lot longer to cool down.... cuz of the the stored up heat
inside a bigger thermal mass.

### On a related subject.... if I remember correctly, in
Eimac's .. "care and feeding" for thermal properties... copper
was ... '1.0' and aluminium was '.57' IE: aluminium
doesn't conduct heat worth banana's... compared to copper !
Steel, and stainless steel is a LOT worse......... just
something to keep in mind.

## A few months back.... I bought a Fluke "Mini 62" IR point and
shoot thermonter.... comes with a built in laser pointer.... and can
be switched from C to F as well. Works slick.... and will
give instant readings onto one LCD display ... and a 2nd
display will always hold the peak highest temp. [both backlit to
boot] By holding the trigger down solid... and moving the
laser pointer about slowly... or quickly.... you can find hot
spots all over the place ! You can see quickly where you are
leaking heat from the outside of a home.... measure exhaust
manifold temps, xfmr's... tank coils... find where ur attic is
not insulated properly [heat radiating down from a ceiling... in
just one spot], and doz's of other uses..... like measuring
exhaust air temp from a linear... Air conditioning problems in the
home or car. This Fluke 62 goes from below freezing
[instant temp readings of ur fridge/deep freezer] to something
like 900 deg F. It will easily differentiate between one part of
a tank coil.... and another portion... just a few mm away. A
great bargain for around $100.00 Shop around.

### IMO.... since a huge portion of the drive power on a GG linear
[ in this case, 640w of the 800 w of drive used] appears in the
output.... I'd consider that ... "free extra eff".

### In any event... anode dissipation is REDUCED... if apparent
eff is UP.

## DC plate input - power out = anode diss. What am I
supposed to do.... subtract the drive power... from the power
output 1st.... THEN calculate plate diss ??? Nobody is about
to do that.... so why bother subtracting the drive power from the
output, to cal eff ?

### I tried several experiments by varying the loaded tank Q on
various bands... and also varying the loaded tank Q on the tuned
input network. Now Rauch will tell you tank Q makes no diff..
and is not important.... and a loaded Q of "22" is just fine.....
fact is loaded Q on a tank circuit DOES make a big
difference. A loaded Q of around 3.3 for a tuned input is fine
[this would equate to Q =2 doing it Rich's way]. A loaded Q
of 10-12 [new method] [ 8-10 old method] is ample for the high
power PI output. You start running a Q of 12-22 [new
method].... you can easily see, and measure effects asap. The
circulating currents skyrocket... tank coils + bandswitch / roller
inductor conacts heat up.... eff DROPS, amp tuning becomes narrow
banded... requiring more frequent tune ups, when u qsy etc.

### On a tuned input.... I tried a Q of 5.... eff drops..esp on
the higher bands. We used bird line sections on both the
input/output of the tuned input circuit [consisted of 2 x
broadcast variables + a tapped 4 uh coilt] output through the 2nd
line section... then into a 50 ohm load was 150-160w . By
INcreasing the small coil's uh tap... just a tiny bit.....
lowering the Q.... and power out of the tuned input... shot up to
195 w.

### with too high a Q on a tuned input... we could actually get
the 5/32 " solid copper 4uh coil good and warm on the high
bands 20-17-15m.

### IF the tuned input is NOT done correctly..... it will kill
ur eff.. real fast. Locating the C2 tuned input variable cap
closer to the tube socket/ and/or installing a small 100 pf NPO
doorknob next to the socket..[ in effect moving a portion of C2
closer to the socket] will improve the eff on the higher bands.

### I'd say we may well be arguing semantics here.... but I'd
say it's just one more advantage of GG amps.... better apparent
eff... and slightly lower plate diss.

Later... Jim VE7RF

> 73
> Peter
>

Help - Need Alpha 99 PS/xfmr info - revisited

Tony King - W4ZT
 

Hi Group,

I am still looking for the schematic and hookup info for the Alpha 99 HV
transformer. If you have that information that you would be willing to share, please contact me. There were exactly ZERO responses to my last request.

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
Re: Tank eff......WAS 3 - phase HV supply

pentalab
 

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

Hey guys,

don't make a fuss about the last killowatt :-))))))))))))))))

Cheers, Dick
PA3DUV


----- Original Message -----
From: Peter Voelpel
To: ham_amplifiers@...
Sent: Wednesday, October 04, 2006 10:29 PM
Subject: RE: [ham_amplifiers] Re: 3 - phase HV supply


Sorry,


Indeed, for 25KW out one needs 45KVA, but only in class B.
67% efficiency is a bit high in class AB, it will be around 63%
minus loss in the pi-network.
Some of the output in a GG amp is coming from the driver, so
efficiency is NOT= output*100%/input power...

### How come all the tetrode fellows always say that ?? We
carefully measured the eff on this latest 6000A7 linear... and
got 67%. Now granted... the wattmeter slug could be a little
high... the plate current + HV meter's could be a little low...
skewing the results.

### Figure maybe 1% loss in the tank circuit... from the coil.
And more like almost 2% on 10m.[ 1-2% of the power output]
The kicker is.... on 10m...all that tank coil heat is being dumped
into just 2 x turns..... vs less heat being dumped into the
ENTIRE coil (or a portion of it)... on the lower bands.

### In various tests I have done... one would think that on say a
20-10m coil.... that when on say 15m.... that the adjacent
unused portion of the coil would heatsink the used portion......
it sorta does... poorly. It ends up the used portion will get
hot... the unused portion [next turn over] runs barely warm... go
figure.

### BTW.... most Vac caps have an unloaded Q of around 5000....
compared to a typ tank coil of 100-300. IMO... most of the tank
losses are going to be in the tank coil... interconnecting
straps.... bandswitch contacts, etc.

### You need very very few watts to heat up a tank coil....esp
hollow tubing. With solid material... like say 8 ga wire
[used on the L4B 2 x 3-500Z] used on 80/40m.. or say solid 6
ga wire used on some 20m coils.... it just takes longer to heat
up..... the flipside is... with any solid material.... it takes a
helluva lot longer to cool down.... cuz of the the stored up heat
inside a bigger thermal mass.

### On a related subject.... if I remember correctly, in
Eimac's .. "care and feeding" for thermal properties... copper
was ... '1.0' and aluminium was '.57' IE: aluminium
doesn't conduct heat worth banana's... compared to copper !
Steel, and stainless steel is a LOT worse......... just
something to keep in mind.

## A few months back.... I bought a Fluke "Mini 62" IR point and
shoot thermonter.... comes with a built in laser pointer.... and can
be switched from C to F as well. Works slick.... and will
give instant readings onto one LCD display ... and a 2nd
display will always hold the peak highest temp. [both backlit to
boot] By holding the trigger down solid... and moving the
laser pointer about slowly... or quickly.... you can find hot
spots all over the place ! You can see quickly where you are
leaking heat from the outside of a home.... measure exhaust
manifold temps, xfmr's... tank coils... find where ur attic is
not insulated properly [heat radiating down from a ceiling... in
just one spot], and doz's of other uses..... like measuring
exhaust air temp from a linear... Air conditioning problems in the
home or car. This Fluke 62 goes from below freezing
[instant temp readings of ur fridge/deep freezer] to something
like 900 deg F. It will easily differentiate between one part of
a tank coil.... and another portion... just a few mm away. A
great bargain for around $100.00 Shop around.



### IMO.... since a huge portion of the drive power on a GG linear
[ in this case, 640w of the 800 w of drive used] appears in the
output.... I'd consider that ... "free extra eff".

### In any event... anode dissipation is REDUCED... if apparent
eff is UP.

## DC plate input - power out = anode diss. What am I
supposed to do.... subtract the drive power... from the power
output 1st.... THEN calculate plate diss ??? Nobody is about
to do that.... so why bother subtracting the drive power from the
output, to cal eff ?

### I tried several experiments by varying the loaded tank Q on
various bands... and also varying the loaded tank Q on the tuned
input network. Now Rauch will tell you tank Q makes no diff..
and is not important.... and a loaded Q of "22" is just fine.....
fact is loaded Q on a tank circuit DOES make a big
difference. A loaded Q of around 3.3 for a tuned input is fine
[this would equate to Q =2 doing it Rich's way]. A loaded Q
of 10-12 [new method] [ 8-10 old method] is ample for the high
power PI output. You start running a Q of 12-22 [new
method].... you can easily see, and measure effects asap. The
circulating currents skyrocket... tank coils + bandswitch / roller
inductor conacts heat up.... eff DROPS, amp tuning becomes narrow
banded... requiring more frequent tune ups, when u qsy etc.

### On a tuned input.... I tried a Q of 5.... eff drops..esp on
the higher bands. We used bird line sections on both the
input/output of the tuned input circuit [consisted of 2 x
broadcast variables + a tapped 4 uh coilt] output through the 2nd
line section... then into a 50 ohm load was 150-160w . By
INcreasing the small coil's uh tap... just a tiny bit.....
lowering the Q.... and power out of the tuned input... shot up to
195 w.

### with too high a Q on a tuned input... we could actually get
the 5/32 " solid copper 4uh coil good and warm on the high
bands 20-17-15m.

### IF the tuned input is NOT done correctly..... it will kill
ur eff.. real fast. Locating the C2 tuned input variable cap
closer to the tube socket/ and/or installing a small 100 pf NPO
doorknob next to the socket..[ in effect moving a portion of C2
closer to the socket] will improve the eff on the higher bands.

### I'd say we may well be arguing semantics here.... but I'd
say it's just one more advantage of GG amps.... better apparent
eff... and slightly lower plate diss.

Later... Jim VE7RF

73
Peter
[Fwd: Re: [Amps] Boycott New Chinese linear Amplifier]

pentalab
 

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

This AMPS list admin sure is getting paranoid,
needs to see a shrink maybe.

73 Jim SM2EKM
### agreed.... or he could just get... "free" advice here. I'm
suggesting 500 mg of Prozac 3 x times a day... + a shot of
whiskey.... stay away from computer's, "the internet".... and
perhaps he could perform self electro shock therapy... with
just a variac and HV supply.....EG: He could hi-pot test
himself..... to say 60 ma. After all that... he then needs
to get a life.

73 Jim VE7RF



I told you morons to stop this thread. Nothing techinical here.
Am I going to have to throw you all out of here. The list founder
told me to clean up this mess and I will.

-----------------------------------------------------------
Sign up and get your 30GB webmail at www.30gigs.com now!
_______________________________________________
Amps mailing list
Amps@...
Re: Hi-pot tester

GGLL
 

It was, in fact I used a variable frequency generator to see what the optimum fqcy. could be, but had no great success. Again, I have yet to experiment a bit more.

Best regards
Guillermo - LU8EYW.

Hsu escribi:

Hi,Guillermo,
I think your square wave generator's freqence is too high?the ignition automotive coils's is iron not ferrite, the frequence
must below kilo hertz
73! Hsu
u may be in the good direction; I did not tried with TV flyback transformers, but did once some experiments with old ignition automotive coils, excited with a square wave generator and a darlington transistor amplifier. I could never get more than 400 volts pk-pk. With 13.8V supply.
The circuit was not optimized also due to lack of time for another tasks, but I think one could get better results.
More experimentation is in order here.
Best regards
Guillermo - LU8EYW.
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Re: Chortle of the Week

 

On Oct 4, 2006, at 8:07 PM, Tony King - W4ZT wrote:

Looks like it never made it to their archives.
It seems that ham_amps is becoming the Administrator Bypass Bulletin Board for AMPS

Tony W4ZT

Phil Clements wrote:
A post on the AMPS reflector that got by the censor today was from
Bob, W6TR; the thread was about the copying of the AL-811 amp in China.

"Isn't it time to bring the curtain down on this thread? Copying an
Ameritron amplifier is like trying to perform a hemorrhoid transplant."

Bob W6TR

This made my day!

(((73)))
Phil, K5PC


Yahoo! Groups Links










R L Measures, AG6K, 805.386.3734
r@..., , rlm@..., www.somis.org
Re: O.T. The "other" list ...aka .... Tom R @%&H

 

Maybe its for a friend, hmmm....maybe "the administrator"?

73 Jim SM2EKM / Sri I couldnt resist
----------------------------------------------------------------

pentalab wrote:

### Go to Tom's website sometime. His AL-1500 looks nice..... SO does the pix of the YC-156 10 kw+ output "medical amplifier" in his workshop... complete with taps for 160-10m !
### what's he gonna do with a HB "medical linear"..... do a little diathermy on 14.175 Mhz ? ?
later.......Jim VE7RF
Re: 3 - phase HV supply

 

Hi Dick,

PA3DUV wrote:
Sasha,

That's a joke! Most houses in the Lowlands are pre wired for 3 phase mains.
That's exactly what I've said on the phone to the lady in Eneco - it must be a joke!
They've said that I have to fill-in some request form where I should explain and
justify the need for the 3-phase for the house in the residential area and only
after they approve it I can make payment (little bit over 1000) and wait for
couple of months before they do it.
Needles to say, I considered this to be very poor service so I turned them down.
Anyway, as my house is very close to the downtown Rotterdam and I can't put up
antennae system for any serious work, I'll do my contesting from YT0A (YU1EXY)
contest location where there are no issues like this - including access to the 3-phase
and some serious aluminum in the air...
Just to stay on amplifiers topic, anyone knows source for the EBM PAPST blowers ?
I am looking for couple of G2E140 (or their equivalent - Air Control, or something similar)
for the decent price. I've found new ones for ~ 200 a piece, which is quite expensive.
It will be used for a single GU84B - one for HF and and another one for VHF.

Cheers,
Sasha YZ6X/PA

I build my house in the mid 90's and the service panel has 4 wires + ground coming in. They only need to add 2 fuses and change out the meter. The utility is Essent and they charged me 175 Euros to do it. I had to rewire everything after the meter myself and add a three phase breaker and diff switch. That was an easy job though and did not cost me near Euro 1000.- ;-))

Cheers, Dick
PA3DUV
[Fwd: Re: [Amps] Boycott New Chinese linear Amplifier]

 

This AMPS list admin sure is getting paranoid,
needs to see a shrink maybe.

73 Jim SM2EKM
Re: 3 - phase HV supply

PA3DUV
 

开云体育

Hey guys,
?
don't make a fuss about the last killowatt :-))))))))))))))))
?
Cheers, Dick
PA3DUV
?
?

----- Original Message -----
Sent: Wednesday, October 04, 2006 10:29 PM
Subject: RE: [ham_amplifiers] Re: 3 - phase HV supply

Sorry,

Power in a 3-phase supply is:

P=sqrt3*U*I*cos phi
P=1,73*400*35=24220

Indeed, for 25KW out one needs 45KVA, but only in class B.
67% efficiency is a bit high in class AB, it will be around 63% minus loss
in the pi-network.
Some of the output in a GG amp is coming from the driver, so efficiency is
NOT= output*100%/input power...

73
Peter

________________________________

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

--- In ham_amplifiers@yahoogroups.com
amplifiers%40yahoogroups.com> , "Peter Voelpel"
wrote:
>
> Hi Dick,
>
> 3x35A is a 230/400V 25KW inlet.
> For 40KW 63A fuses are to be installed, mine are 80A

### whoa. 35 A x 400 V = 14 kw per phase. x 3 phases = 42
kva.

### To get 25 kw out [assuming 67 % eff on the lower bands]
25,000/ .67 = 37,323 watts of DC input. = 37.323 x 1.21 = 45.149
Kva.

Re: Chortle of the Week

Tony King - W4ZT
 

Looks like it never made it to their archives.

Tony W4ZT

Phil Clements wrote:

A post on the AMPS reflector that got by the censor today was from Bob, W6TR; the thread was about the copying of the AL-811 amp in China.
"Isn't it time to bring the curtain down on this thread? Copying an Ameritron amplifier is like trying to perform a hemorrhoid transplant."
Bob W6TR
This made my day!
(((73)))
Phil, K5PC
40701 - 40720 of 41174