Hi Dick,
We found not much more benefit from increasing coil size beyond 40cm
diameter on 80m.
Coils sized from 25-40cm diameter were close in competition, just the wide
of the S-meter needle in difference.
Band change was done by using banana plugs right at the coils windings.
Coils were air coils wound either with 3-4mm copper wire or tubing.
Still got mine (25cm)
From our 80m mobil gang (~20 qro) in the seventies, LX1GM was the strongest
station.
He was using 5 additional alternators in his car, beside 6x100AH batteries
and the inverter.
The inverter 900V/600Hz fed 12xPL36 to 2500W out (keydown) on 80-20m.
While driving through the Luxembourg city shopping mile at night he switched
on lots of burgler alarms ;-))
73
Peter
________________________________
From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of PA3DUV
:-) Alles klar Peter. What diameter loading coil would you suggest for a
multiband centerloaded vertical with 3500 kilocycles as the lowest
frequency.
|
Hi,
Has anyone built an amplifier with a gu-84b tetrode? In the datasheet
the maximum anode voltage is 2.2kilovolt, but I've found a few websites
where they apply 3.5 to 4 kilovolt.
I wonder if this is a good idea, and if the life time of the tube is
changed with this higher voltage.
Who has experience ?
best regards,
Jan , ON6ZG
|
Re: GG Push-pull Amplifier
OK Hsu -- Rather than sending it and something happening I just uploaded it to my website and you can download it at your convenience. Go to: < amp.zip> or just go to my website at: choose Downloadable files from the menu and then the file is "400w amp.zip" There were two pages so I just zipped them both together and they're just over a meg. Good luck with your project --- I hope this helps. I hope I can catch you on the air sometime. 73, Jim - K5LAD On 11 Jan 2007 at 13:18, Hsu wrote:
Jim!
Great!I have not get the information.
please send it to my another mail box bd2rh@....
this e-mail located in China can notrecieve large file
from oversea,because of fiber problem. in Taiwan Gulf.
Thanks in advance!
73! Hsu
----- Original Message -----
From: K5LAD@...
To: ham_amplifiers@...
Sent: Thursday, January 11, 2007 12:32 PM
Subject: Re: [ham_amplifiers] GG Push-pull Amplifier
Hi Hsu --
Have you been able to find the information you
needed from the Holiday issue 1976 73 Magazine?
If not I have that issue in hand.
73,
Jim - K5LAD
On 6 Jan 2007 at 22:10, Hsu wrote:
Hi,
I have seen a diagram in Modern Electronic Circuits Reference Manual
(John Markus),origional article in 73 Magzine, Holidy Issue 1976,
P22-23.Author:B.Baird,"Build This Inexpensive 400 Watt Amplifier".It
is a GG Push-pull Amplifier useing a pair 7094, without input
matched network,I'm very interested its plate network, it without
slug coils and can work in all ahm band and need not change the
coil.I'm sad I have not full article. Could some someone can saan or
take some photos and send the article to me ?It is a very
interesting design, Although it without input Pi network, but I
think it still have a better matching than Single End amplifier. Is
that right?
73! Hsu
"It's so simple to be wise. Just think of something
stupid to say and then don't say it." -- Sam
Levenson
=======================================
My Web Page -
"It's so simple to be wise. Just think of something stupid to say and then don't say it." -- Sam Levenson ======================================= My Web Page -
|
Re: GG Push-pull Amplifier
Jim!
?Great!I have not get the
information.
please send it to my another mail box bd2rh@....
?this e-mail located in China can
not?recieve large file
from oversea?,because of fiber problem. in Taiwan
Gulf.
?? Thanks in advance!
????? 73!
Hsu?
?
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Thursday, January 11, 2007 12:32
PM
Subject: Re: [ham_amplifiers] GG Push-pull
Amplifier
Hi Hsu --
Have you been able to find the information you
needed from
the Holiday issue 1976 73 Magazine?
If not I have that issue in
hand.
73,
Jim - K5LAD
On 6 Jan 2007 at 22:10, Hsu
wrote:
> Hi,
> I have seen a diagram in Modern Electronic
Circuits Reference Manual
> (John Markus),origional article in 73
Magzine, Holidy Issue 1976,
> P22-23.Author:B.Baird,"Build
This Inexpensive 400 Watt Amplifier".It
> is a GG Push-pull Amplifier
useing a pair 7094, without input
> matched network,I'm very interested
its plate network, it without
> slug coils and can work in all ahm band
and need not change the
> coil.I'm sad I have not full article. Could
some someone can saan or
> take some photos and send the article to me
?It is a very
> interesting design, Although it without input Pi
network, but I
> think it still have a better matching than Single End
amplifier. Is
> that right?
> 73! Hsu
>
"It's so
simple to be wise. Just think of something
stupid to say and then don't say
it." -- Sam
Levenson
=======================================
My
Web Page -
|
Re: GG Push-pull Amplifier
Hi Hsu -- Have you been able to find the information you needed from the Holiday issue 1976 73 Magazine? If not I have that issue in hand. 73, Jim - K5LAD On 6 Jan 2007 at 22:10, Hsu wrote: Hi,
I have seen a diagram in Modern Electronic Circuits Reference Manual
(John Markus),origional article in 73 Magzine, Holidy Issue 1976,
P22-23.Author:B.Baird,"Build This Inexpensive 400 Watt Amplifier".It
is a GG Push-pull Amplifier useing a pair 7094, without input
matched network,I'm very interested its plate network, it without
slug coils and can work in all ahm band and need not change the
coil.I'm sad I have not full article. Could some someone can saan or
take some photos and send the article to me ?It is a very
interesting design, Although it without input Pi network, but I
think it still have a better matching than Single End amplifier. Is
that right?
73! Hsu
"It's so simple to be wise. Just think of something stupid to say and then don't say it." -- Sam Levenson ======================================= My Web Page -
|
--- In ham_amplifiers@..., "badgerscreek" <qrp73@...> wrote:
I think those Yellow Top Batteries are called Optima Batteries?
I dont know why nobody is concerned about having their brains so
close to the antenna? I mean sitting in the near field of the
antenna running 1 or more kilowatts at the higher frequencies would have me
worried. Maybe the adrenalin rush is more potent than worrying about your health, or maybe theres no danger?
Greg
I've heard of this causing some health problems for a few in those key-downs they do. Long term exposure though could be pretty bad I'd think. Yup, that's the name of those batteries, I couldn't remember it when I wrote the post.
|
Mobile power supplies revisited
Here's another thought, more geared towards the gentleman in .eu who was looking at running a bunch of 2 volt batteries in series, and home charging it.
I have done this in the past, and although it isn't the best method, since your going to use 2 volt batteries, you can still accomplish this and stay within the realm of 16 volts.
Take 2 of those 2 volt batteries and run them in series, creating 1X 4 volt cell.
Connect that in series, neg from the new bank to + on the car battery, and run your amp from the + side of the new battery bank. From vehicle ground to amplifier B+, you will see app 16 volts.
Now, the trick is here...
Take ONLY the B+ out from the ALTERNATOR (I always disconnect the vehicle CHARGE lead at the alternator, then run a dedicated lead from the alt to the battery stack), and connect it as well to the top of the battery stack (to the 16 volt side).
Since the cars electronics will all still see 12 volts, and the alternator will have to produce 18 volts to charge the 16 volt system, everything charges nicely.
I also think it is best to take and run a relay / solenoid setup to disconnect the extra 4 volt stack when not being used, to prevent overcharging. Usually 10 to 45 minutes of charging while driving around is sufficient. Just use a solenoid to disconnect the B+ from the alt to the top of the 16 volt stack to the + / - junction of the 12 and 4 volt batteries.
This works well in systems where you can't install a second alternator. Your car works fine, the amp works fine, everything charges nicely, BUT, you don't get something for nothing. Your alternator is usually running > manuf ratings, and you won't see rated Aout at 18 volts.... Expect about 20 percent less... Or even less efficiency. Still, makes it easy to run increased collector voltage cheaply.
--Toll_Free
|
Re: The real benefits of running qro.
Now this is what hamming is all about!
?
Oh, yes!
?
The knife switches with 5/16” thick
copper bars,
the contactors that go CHUNG!.
?
The smallest RF connector in your shack is
a 7/16DIN
and the stuff going out to your antenna is
1-5/8”? diameter.
?
My friend Dale runs two 4-1000A’s
modulated by two 4-1000A’s
on A-M, with reactors, no less. Push-pull!
?
He says he barely uses more than $100.00 of
electricity a month
with that puppy.
?
Can you imagine Guglielmo Marconi’s
reaction the first time
he keyed that 50KW spark station on Cape Cod? The station’s biography
says that neighbors a half-mile away could
hear the spark.
?
Thanks for the great posting.
Hal
?
toggle quoted message
Show quoted text
From: ham_amplifiers@...
[mailto:ham_amplifiers@...] On
Behalf Of Philip Leonard WV?T
Sent: Wednesday, January 10, 2007
5:23 PM
To: ham_amplifiers@...
Subject: Re: [ham_amplifiers] Re:
The real benefits of running qro.
?
pentalab
wrote:
> ### qro heats ur
home... makes u feel better, reduces stress.. u
> feel like u just beat collins/henry/harris, at their own game...
> lots of satisfaction, ur
friends are all impressed..esp wide eyed
> computer geeks, and it's fun to watch plate meter's bouncing
> up/down...ditto with wattmeter. You have the only 0-5 A plate
> meter in town. You have the only 0-1 A grid meter in town. You
> have the only 10/25 kw slug in town. Ur
plate xfmr will power 8 x
> homes in winter. Ur
girlfriend will be dully impressed. You have
> more power than the local college FM station. Ur friends with 25
> watt push pull tube audio amps are really impressed, [esp with a 2
> x4-1000 amp.. and a window, and tubes cherry red] U have more power
> than 99.99% of the hams on the planet. Ur mother would be proud.
> Pundits think you are actually a 'broadcast engineer'. 11m ops are
> really impressed. You can dim all the lights on your street. Who
> else can say they actually smoked the pole-pig in front of their
> home.... and plunged the entire street into darkness. No need for
> counselling or self medication. You are more focused, and have
> better concentration..esp around 8-10 kv. You can light up
> several 8' fluorescent tubes in your back yard... with no wires
> attached. People stay clear of you in aisle 6 of your local grocery
> store. You can casually mention stuff at the local hamfest... like
> how you set the tree's on fire.. and blew the end insulator's off ur
> dipole. You can give a real Corona
demo late at night. You once
> melted RG-17 on 10m. QST will never publish your schematic.
This is one of the funniest things I've read in a long long time! Thank
you. I'm going to print this out and hang it on the wall!!
Philip
|
Re: The real benefits of running qro.
pentalab wrote: ### qro heats ur home... makes u feel better, reduces stress.. u feel like u just beat collins/henry/harris, at their own game... lots of satisfaction, ur friends are all impressed..esp wide eyed computer geeks, and it's fun to watch plate meter's bouncing up/down...ditto with wattmeter. You have the only 0-5 A plate meter in town. You have the only 0-1 A grid meter in town. You have the only 10/25 kw slug in town. Ur plate xfmr will power 8 x homes in winter. Ur girlfriend will be dully impressed. You have more power than the local college FM station. Ur friends with 25 watt push pull tube audio amps are really impressed, [esp with a 2 x4-1000 amp.. and a window, and tubes cherry red] U have more power than 99.99% of the hams on the planet. Ur mother would be proud. Pundits think you are actually a 'broadcast engineer'. 11m ops are really impressed. You can dim all the lights on your street. Who else can say they actually smoked the pole-pig in front of their home.... and plunged the entire street into darkness. No need for counselling or self medication. You are more focused, and have better concentration..esp around 8-10 kv. You can light up several 8' fluorescent tubes in your back yard... with no wires attached. People stay clear of you in aisle 6 of your local grocery store. You can casually mention stuff at the local hamfest... like how you set the tree's on fire.. and blew the end insulator's off ur dipole. You can give a real Corona demo late at night. You once melted RG-17 on 10m. QST will never publish your schematic. This is one of the funniest things I've read in a long long time! Thank you. I'm going to print this out and hang it on the wall!! Philip
|
:-) Alles klar?Peter. What diameter loading coil would you suggest for a multiband
centerloaded vertical with 3500 kilocycles as the lowest frequency.
?
Cheers, Dick
PA3DUV
?
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Wednesday, January 10, 2007 8:50
PM
Subject: RE: [ham_amplifiers] Re: hi
power mobile
Beside, when using real loading coils and not such 5" mickey mouse
coils,
500W are all one needs to work any station heard on 80m and break
most dx
pileups easily.
73
Peter
-----Original
Message-----
From: ham_amplifiers@yahoogroups.com
[mailto:ham_amplifiers@yahoogroups.com]
On
Behalf Of 1800 Toll Free
What you need has been done, by the car stereo
crowd years ago, you just
need to do a little bit of lookin around before
you spend the hard earned
dollars :)
|
The 4 feet aerea around my 80m vertical looks the same.
To prevent grass growing near the feedpoint,
I drain the ground regularly with vineger.
73
Peter
________________________________
From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of Robert B. Bonner
Back in the 70's a couple of my club members took a tour at 830 WCCO-AM in
the Minneapolis area. They are a 50KW full time station. They noticed that
for the first 10 or more feet around the base of the tower there was NO
GRASS GROWING AT ALL, just dirt. The rest of the lawn was immaculate. Does
this tell you something also? It made a heck of an impression on those guys
back then.
|
Beside, when using real loading coils and not such 5" mickey mouse coils,
500W are all one needs to work any station heard on 80m and break most dx
pileups easily.
73
Peter
toggle quoted message
Show quoted text
-----Original Message-----
From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of 1800 Toll Free
What you need has been done, by the car stereo crowd years ago, you just
need to do a little bit of lookin around before you spend the hard earned
dollars :)
|
I worked for motorola for a couple years. We had a guy who thought nothing of climbing a tower with multiple 400 MHz rigs going. I pointed?out to him that he was in danger but blew me off. He always had a tan. Last?I heard he was still fighting brain cancer. I also don't own a microwave built to third world quality controls.
"Robert B. Bonner" wrote:
I used to work for a tower company back many years ago.? My buddy (who owned the company and a ham) finally sold out and semi-retired maybe 10 years ago now.
He told me, he had to do some work on a 50 or 100KW FM BC tower and scheduled with the engineer to have the transmitter reduced to low power for the job.? It was supposed to be brought down to like 10KW ERP. For the day.? My buddy double checked and said this absolutely HAS TO BE DONE.? He preferred it to be brought offline completely but the owner said no way? That day the engineer wasnt available to confirm he had reduced the power and my buddy went ahead with the
project.
Later he felt really sick and was in major distress for nearly a month.? Turns out dipstick engineer didnt do his job as promised and he spent half a day on the tower getting his guts cooked.
This was about 20 years ago and Hes had major problems ever since.
Were talking major power at bad frequencies
Back in the 70s a couple of my club members took a tour at 830 WCCO-AM in the Minneapolis area.? They are a 50KW full time station.? They noticed that for the first 10 or more feet around the base of the tower there was NO GRASS GROWING AT ALL, just dirt.? The rest of the lawn was immaculate.? Does this tell you something also?? It made a heck of an impression on those guys back then.
I wouldnt give a couple KW on 20 meters a second thought, however, Im thinking 100KW in a mobile install is pretty risky at 27 MHz.
BOB DD
From: ham_amplifiers@yahoogroups.com [mailto:ham_amplifiers@yahoogroups.com] On Behalf Of Harold Mandel
Sent: Wednesday, January 10, 2007 11:49 AM
To: ham_amplifiers@yahoogroups.com
Subject: RE: [ham_amplifiers] Re:hi power mobile
On the Bechtel/AWS project just before, during and after the WTC disaster we
serviced cell site antennae throughout Manhattan as well as all the other boroughs.
When going out on the roof of WTC1 it was necessary to wear a grounded RF suit with internal EME detector calibrated for alarms at less than 50 uW-to-alarm.
The stupidest work picture I ever saw were these two geniuses climbing on the Empire State Building broadcast array in the middle of the day without hard hats, without safety glasses, without gloves. The picture was taken from above, so there was a third genius on the array. The photo was
distributed by the ES&H people at Bechtel.
Hal W4HBM
From: ham_amplifiers@yahoogroups.com [mailto:ham_amplifiers@yahoogroups.com] On Behalf Of Robert B. Bonner
Sent: Wednesday, January 10, 2007 11:55 AM
To: ham_amplifiers@yahoogroups.com
Subject: RE: [ham_amplifiers] Re:hi power mobile
There is very little tissue heating at HF.
As you start passing through Vhf to UHF you have severe issues.
Some very
serious tissue effects can happen at 432. My 432 amp can generate 2KW out.
With big antennas at those frequencies ERP's in the mega watt range are
possible at ham power levels.
The original microwave ovens ran around 900MHz well there's another ham band
too.
You have more problems stopping pacemakers at HF. I wonder if there could
be any liability at a stop sign if the person in the car next to you keeled
over because you were trying to work the 7Alpha on 20 meters from the car?
At the old WB0DRL VHF/UHF contest station they tuned the amps with microwave
leakage detectors, you know the tool for testing ovens. All the stations
had them. The shack was RF tight, however when the door was opened the
detectors would all start banging off the pegs to the CW. Everybody would
scream "Shut that door"
I declare Ham Radio is completely safe. What? (Battle Cry heard from the LT
as you charge the enemy with only a
knife in your teeth) YOU WANT TO LIVE
FOREVER?
BOB DD
-----Original Message-----
From: ham_amplifiers@yahoogroups.com [mailto:ham_amplifiers@yahoogroups.com]
On Behalf Of badgerscreek
Sent: Wednesday, January 10, 2007 5:34 AM
To: ham_amplifiers@yahoogroups.com
Subject: [ham_amplifiers] Re:hi power mobile
I think those Yellow Top Batteries are called Optima Batteries?
I dont know why nobody is concerned about having their brains so
close to the antenna? I mean sitting in the near field of the antenna
running 1 or more kilowatts at the higher frequencies would have me
worried. Maybe the adrenalin rush is more potent than worrying about
your health, or maybe theres no danger?
Greg
--- In ham_amplifiers@yahoogroups.com, "craxd" wrote:
>
> --- In ham_amplifiers@yahoogroups.com, "pentalab" >
> wrote:
> >
> > --- In ham_amplifiers@yahoogroups.com, 1800 Toll Free
> > > wrote:
> > >
> > > It's kind of funny watching the thread about the mobile
> amplifiers
> > and
> > > voltage requirements.
> >
> > ##### I have zero experience with it. I was just waiting for
> you
> > to come out of the wood work.... since I knew you guys had this
> down
> > pat.. and was all old news. The deep cycle communications
> > batteries work pretty good.
>
>
> Right now, they're running those yellow top batteries with the spiral
> cells. They claim these to be the best. Also, there's really no limit
> to the batteries that you parallel together to get the power required
> you need. The more batteries, the longer you can run. I've seen the
> big 24V batteries used in diesel rigs too ran in these set ups. The
> ones you want have the largest amp-hour ratings.
>
>
> >
> > ### I also read in an old QST... where they would use 2 x
> > batteries in series.... like those used in golf carts..... but one
> > was 6 V... and the other was 8 V. [didn't even know u could get
> > deep cycle batteries... big ones... in 6 + 8 V ] Then ur car
> > regulator would charge em to 14 .3 V..... then with engine OFF....
> > ur small 706-mk-2-G would last way longer. That setup was also
> > used in some Field day event's.
> >
> >
> >
> >
> > > They use a charging system consisting of a 24 volt alternator,
> and
> > run
> > > parallel / series combos of standard car batteries (or standard
> > and deep
> > > cycle, if they are smart) to have a 24 volt electric system.
> One
> > > alternator, and a pair of batteries will power quite a large
> > system, as
> >
> > ### Don't some of em use train alternator's ??? Think they
> > were split stator, dual rotor.... or split rotor, dual stator...
> > made by Neville Leece.... at 1000 A per stator ?? Or was this
> > for the tube setups ??
>
>
> They'll use like 6 of the Leece Neville alternators under the hood to
> power the big solid state amps. Some have used generators that can
> provide
115/230 Vac too ran off the belt.
>
>
> >
> > ### I still haven't seen any detailed website on this hi power
> > mobile stuff. Trying to generate the power is a huge project in
> > itself. RFI, etc... Rf decks... is another issue. You are
> > right... hams are just trying to reinvent the wheel.
>
>
> Right, not a lot has been published on this as it was all done sort
> of under the table away from the FCC.
>
>
> >
> > Later... Jim VE7RF
> >
> >
> > > --Toll_Free
> > >
> >
>
>
> Best,
>
> Will
>
Yahoo! Groups Links
|
The Touota Prius has a 200v, 250A-max Ni-MH battery. The battery recharges from the electric motor-generator that is powered by the 1500cc gas engine or from braking the already-moving vehicle. On Jan 10, 2007, at 9:07 AM, Robert B. Bonner wrote:
I have a couple alternator companies quoting a 48 volt alternator
(54V) at 100 amps for my pickup. I figure a couple 24 v truck
batteries in series in a bed mounted battery box with a custom
remote mounted amp. I’ll build up a couple 50V amplifier modules.
I think the CBer’s are right, just add an electrical system for
what you think you need… Maybe I can get away from the 750MCM
battery cables that way…..
BOB DD
From: ham_amplifiers@...
[mailto:ham_amplifiers@...] On Behalf Of PA3DUV
Sent: Wednesday, January 10, 2007 9:09 AM
To: ham_amplifiers@...
Subject: [Norton AntiSpam] Re: [ham_amplifiers] Re:hi power mobile
Will,
Thanks for the input.
After reading all the post on this subject I will finish the power
supply as follows:
8 x 2 volt 230 Ah cells feeding the amplifier stack
16 volt 3 stage charger, input voltage 230 V AC
12 VDC => 230 VAC sine wave inverter to supply a limited 230 AC for
the charger while driving
an external 230 VAC connector on my trailer hitch so I can charge
the batteries when the car is on the driveway
A better alternative would be to install a second 16 volt DC
alternator, but there is simply no space for a second alternator.
Cheers, Dick
PA3DUV
----- Original Message -----
From: craxd
To: ham_amplifiers@...
Sent: Wednesday, January 10, 2007 2:00 AM
Subject: [ham_amplifiers] Re:hi power mobile
--- In ham_amplifiers@..., "pentalab" <jim.thomson@...>
wrote:
--- In ham_amplifiers@..., 1800 Toll Free
<TollFree1800@> wrote:
It's kind of funny watching the thread about the mobile
amplifiers
and
voltage requirements. ##### I have zero experience with it. I was just waiting for you
to come out of the wood work.... since I knew you guys had this down
pat... and was all old news. The deep cycle communications
batteries work pretty good. Right now, they're running those yellow top batteries with the spiral
cells. They claim these to be the best. Also, there's really no limit
to the batteries that you parallel together to get the power required
you need. The more batteries, the longer you can run. I've seen the
big 24V batteries used in diesel rigs too ran in these set ups. The
ones you want have the largest amp-hour ratings.
### I also read in an old QST... where they would use 2 x
batteries in series.... like those used in golf carts..... but one
was 6 V... and the other was 8 V. [didn't even know u could get
deep cycle batteries... big ones... in 6 + 8 V ] Then ur car
regulator would charge em to 14 .3 V..... then with engine OFF....
ur small 706-mk-2-G would last way longer. That setup was also
used in some Field day event's.
They use a charging system consisting of a 24 volt alternator,
and
run
parallel / series combos of standard car batteries (or standard and deep
cycle, if they are smart) to have a 24 volt electric system. One
alternator, and a pair of batteries will power quite a large system, as
### Don't some of em use train alternator's ??? Think they
were split stator, dual rotor.... or split rotor, dual stator...
made by Neville Leece.... at 1000 A per stator ?? Or was this
for the tube setups ??
They'll use like 6 of the Leece Neville alternators under the hood to
power the big solid state amps. Some have used generators that can
provide 115/230 Vac too ran off the belt.
### I still haven't seen any detailed website on this hi power
mobile stuff. Trying to generate the power is a huge project in
itself. RFI, etc... Rf decks... is another issue. You are
right... hams are just trying to reinvent the wheel.
Right, not a lot has been published on this as it was all done sort
of under the table away from the FCC.
Later... Jim VE7RF
--Toll_Free
Best,
Will
R. L. Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org
|
I used to work for a tower company back many years
ago.? My buddy (who owned the company and a ham) finally sold out and
semi-retired maybe 10 years ago now.
?
He told me, he had to do some work on a 50 or 100KW FM BC
tower and scheduled with the engineer to have the transmitter reduced to low
power for the job.? It was supposed to be brought down to like 10KW ERP. For
the day.? My buddy double checked and said this absolutely HAS TO BE
DONE.? He preferred it to be brought offline completely but the owner said
no way…? That day the engineer wasn’t available to confirm he
had reduced the power and my buddy went ahead with the project.
?
Later he felt really sick and was in major distress for
nearly a month.? Turns out dipstick engineer didn’t do his job as
promised and he spent half a day on the tower getting his guts cooked.
?
This was about 20 years ago and He’s had major
problems ever since.
?
We’re talking major power at bad frequencies…
?
Back in the 70’s a couple of my club members took a
tour at 830 WCCO-AM in the Minneapolis
area.? They are a 50KW full time station.? They noticed that for the
first 10 or more feet around the base of the tower there was NO GRASS GROWING
AT ALL, just dirt.? The rest of the lawn was immaculate.? Does this
tell you something also?? It made a heck of an impression on those guys
back then.
?
I wouldn’t give a couple KW on 20 meters a second
thought, however, I’m thinking 100KW in a mobile install is pretty risky at
27 MHz.
?
BOB DD
?
toggle quoted message
Show quoted text
From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Harold Mandel
Sent: Wednesday, January 10, 2007
11:49 AM
To: ham_amplifiers@...
Subject: RE: [ham_amplifiers]
Re:hi power mobile
?
On the Bechtel/AWS project just before,
during and after the WTC disaster
we serviced cell site antennae throughout Manhattan as well as all
the other
boroughs.
?
When going out on the roof of WTC1 it was
necessary to wear a grounded RF suit
with internal EME detector calibrated for
alarms at less than 50 uW-to-alarm.
?
The stupidest work picture I ever saw were
these two geniuses climbing on the
Empire State
Building broadcast array in the middle of the day
without hard hats,
without safety glasses, without gloves. The
picture was taken from above, so there was
a third genius on the array. The photo was
distributed by the ES&H people at Bechtel.
?
Hal
W4HBM
?
From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Robert B. Bonner
Sent: Wednesday, January 10, 2007
11:55 AM
To: ham_amplifiers@...
Subject: RE: [ham_amplifiers]
Re:hi power mobile
?
There is very little tissue heating at HF.
As you start passing through Vhf to UHF you have severe issues. Some very
serious tissue effects can happen at 432. My 432 amp can generate 2KW out.
With big antennas at those frequencies ERP's in the mega watt range are
possible at ham power levels.
The original microwave ovens ran around 900MHz well there's another ham band
too.
You have more problems stopping pacemakers at HF. I wonder if there could
be any liability at a stop sign if the person in the car next to you keeled
over because you were trying to work the 7Alpha on 20 meters from the car?
At the old WB0DRL VHF/UHF contest station they tuned the amps with microwave
leakage detectors, you know the tool for testing ovens. All the stations
had them. The shack was RF tight, however when the door was opened the
detectors would all start banging off the pegs to the CW. Everybody would
scream "Shut that door"
I declare Ham Radio is completely safe. What? (Battle Cry heard from the LT
as you charge the enemy with only a knife in your teeth) YOU WANT TO LIVE
FOREVER?
BOB DD
-----Original Message-----
From: ham_amplifiers@yahoogroups.com
[mailto:ham_amplifiers@yahoogroups.com]
On Behalf Of badgerscreek
Sent: Wednesday, January 10, 2007 5:34 AM
To: ham_amplifiers@yahoogroups.com
Subject: [ham_amplifiers] Re:hi power mobile
I think those Yellow Top Batteries are called Optima Batteries?
I dont know why nobody is concerned about having their brains so
close to the antenna? I mean sitting in the near field of the antenna
running 1 or more kilowatts at the higher frequencies would have me
worried. Maybe the adrenalin rush is more potent than worrying about
your health, or maybe theres no danger?
Greg
--- In ham_amplifiers@yahoogroups.com,
"craxd" wrote:
>
> --- In ham_amplifiers@yahoogroups.com,
"pentalab" >
> wrote:
> >
> > --- In ham_amplifiers@yahoogroups.com,
1800 Toll Free
> > > wrote:
> > >
> > > It's kind of funny watching the thread about the mobile
> amplifiers
> > and
> > > voltage requirements.
> >
> > ##### I have zero experience with it. I was just waiting for
> you
> > to come out of the wood work.... since I knew you guys had this
> down
> > pat.. and was all old news. The deep cycle communications
> > batteries work pretty good.
>
>
> Right now, they're running those yellow top batteries with the spiral
> cells. They claim these to be the best. Also, there's really no limit
> to the batteries that you parallel together to get the power required
> you need. The more batteries, the longer you can run. I've seen the
> big 24V batteries used in diesel rigs too ran in these set ups. The
> ones you want have the largest amp-hour ratings.
>
>
> >
> > ### I also read in an old QST... where they would use 2 x
> > batteries in series.... like those used in golf carts..... but one
> > was 6 V... and the other was 8 V. [didn't even know u could get
> > deep cycle batteries... big ones... in 6 + 8 V ] Then ur car
> > regulator would charge em to 14 .3 V..... then with engine OFF....
> > ur
small 706-mk-2-G would last way longer. That setup was also
> > used in some Field day event's.
> >
> >
> >
> >
> > > They use a charging system consisting of a 24 volt alternator,
> and
> > run
> > > parallel / series combos of standard car batteries (or standard
> > and deep
> > > cycle, if they are smart) to have a 24 volt electric system.
> One
> > > alternator, and a pair of batteries will power quite a large
> > system, as
> >
> > ### Don't some of em use train alternator's ??? Think they
> > were split stator, dual rotor.... or split rotor, dual stator...
> > made by Neville Leece.... at 1000 A per stator ?? Or was this
> > for the tube setups ??
>
>
> They'll use like 6 of the Leece Neville alternators under the hood to
> power the big solid state amps. Some have used generators that can
> provide 115/230 Vac too ran off the belt.
>
>
> >
> > ### I still haven't seen any detailed website on this hi power
> > mobile stuff. Trying to generate the power is a huge project in
> > itself. RFI, etc... Rf decks... is another issue. You are
> > right... hams are just trying to reinvent the wheel.
>
>
> Right, not a lot has been published on this as it was all done sort
> of under the table away from the FCC.
>
>
> >
> > Later... Jim VE7RF
> >
> >
> > > --Toll_Free
> > >
> >
>
>
> Best,
>
> Will
>
Yahoo! Groups Links
|
If any of you are seriously interested in QROO/mobile and need
info on battery plants, regulators, alternators and 3-phase inverters,
etc., please contact me off-list. Let me send you the pic of the
Dodge Hemi motor running 7 alternators, all in the cargo area.
Hal
W4HBM
toggle quoted message
Show quoted text
-----Original Message----- From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of 1800 Toll Free Sent: Wednesday, January 10, 2007 11:59 AM To: ham_amplifiers@... Subject: [ham_amplifiers] Re: hi power mobile Will, How does a series regulator for 300 amps look like?
The efficiency from such a regulator seems to questionable, the voltage
difference x current is obviously dissipated and turned into >heat. ([22
loaded - 16] x 300 = 1800 watt) It's all about duty cycle. Most of the motor mauls I saw or had the pleasure of fixing where about the same size as an amp of comparable power output.... ie... One that had 16 active pass devices in it would be the same size as a 16 transistor HF amp. --Toll_Free Yahoo! Groups Links
|
On the Bechtel/AWS project just before,
during and after the WTC disaster
we serviced cell site antennae throughout Manhattan as well as all
the other
boroughs.
?
When going out on the roof of WTC1 it was
necessary to wear a grounded RF suit
with internal EME detector calibrated for
alarms at less than 50 uW-to-alarm.
?
The stupidest work picture I ever saw were
these two geniuses climbing on the
Empire State
Building broadcast array in the middle of the day
without hard hats,
without safety glasses, without gloves. The
picture was taken from above, so there was
a third genius on the array. The photo was
distributed by the ES&H people at Bechtel.
?
Hal
W4HBM
?
From:
ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Robert B. Bonner
Sent: Wednesday, January 10, 2007
11:55 AM
To: ham_amplifiers@...
Subject: RE: [ham_amplifiers]
Re:hi power mobile
?
There is very little tissue heating at HF.
As you start passing through Vhf to UHF you have severe issues. Some very
serious tissue effects can happen at 432. My 432 amp can generate 2KW out.
With big antennas at those frequencies ERP's in the mega watt range are
possible at ham power levels.
The original microwave ovens ran around 900MHz well there's another ham band
too.
You have more problems stopping pacemakers at HF. I wonder if there could
be any liability at a stop sign if the person in the car next to you keeled
over because you were trying to work the 7Alpha on 20 meters from the car?
At the old WB0DRL VHF/UHF contest station they tuned the amps with microwave
leakage detectors, you know the tool for testing ovens. All the stations
had them. The shack was RF tight, however when the door was opened the
detectors would all start banging off the pegs to the CW. Everybody would
scream "Shut that door"
I declare Ham Radio is completely safe. What? (Battle Cry heard from the LT
as you charge the enemy with only a knife in your teeth) YOU WANT TO LIVE
FOREVER?
BOB DD
toggle quoted message
Show quoted text
-----Original Message-----
From: ham_amplifiers@yahoogroups.com
[mailto: ham_amplifiers@yahoogroups.com]
On Behalf Of badgerscreek
Sent: Wednesday, January 10, 2007 5:34 AM
To: ham_amplifiers@yahoogroups.com
Subject: [ham_amplifiers] Re:hi power mobile
I think those Yellow Top Batteries are called Optima Batteries?
I dont know why nobody is concerned about having their brains so
close to the antenna? I mean sitting in the near field of the antenna
running 1 or more kilowatts at the higher frequencies would have me
worried. Maybe the adrenalin rush is more potent than worrying about
your health, or maybe theres no danger?
Greg
--- In ham_amplifiers@yahoogroups.com,
"craxd" wrote:
>
> --- In ham_amplifiers@yahoogroups.com,
"pentalab" >
> wrote:
> >
> > --- In ham_amplifiers@yahoogroups.com,
1800 Toll Free
> > > wrote:
> > >
> > > It's kind of funny watching the thread about the mobile
> amplifiers
> > and
> > > voltage requirements.
> >
> > ##### I have zero experience with it. I was just waiting for
> you
> > to come out of the wood work.... since I knew you guys had this
> down
> > pat... and was all old news. The deep cycle communications
> > batteries work pretty good.
>
>
> Right now, they're running those yellow top batteries with the spiral
> cells. They claim these to be the best. Also, there's really no limit
> to the batteries that you parallel together to get the power required
> you need. The more batteries, the longer you can run. I've seen the
> big 24V batteries used in diesel rigs too ran in these set ups. The
> ones you want have the largest amp-hour ratings.
>
>
> >
> > ### I also read in an old QST... where they would use 2 x
> > batteries in series.... like those used in golf carts..... but one
> > was 6 V... and the other was 8 V. [didn't even know u could get
> > deep cycle batteries... big ones... in 6 + 8 V ] Then ur car
> > regulator would charge em to 14 .3 V..... then with engine OFF....
> > ur
small 706-mk-2-G would last way longer. That setup was also
> > used in some Field day event's.
> >
> >
> >
> >
> > > They use a charging system consisting of a 24 volt alternator,
> and
> > run
> > > parallel / series combos of standard car batteries (or standard
> > and deep
> > > cycle, if they are smart) to have a 24 volt electric system.
> One
> > > alternator, and a pair of batteries will power quite a large
> > system, as
> >
> > ### Don't some of em use train alternator's ??? Think they
> > were split stator, dual rotor.... or split rotor, dual stator...
> > made by Neville Leece.... at 1000 A per stator ?? Or was this
> > for the tube setups ??
>
>
> They'll use like 6 of the Leece Neville alternators under the hood to
> power the big solid state amps. Some have used generators that can
> provide 115/230 Vac too ran off the belt.
>
>
> >
> > ### I still haven't seen any detailed website on this hi power
> > mobile stuff. Trying to generate the power is a huge project in
> > itself. RFI, etc... Rf decks... is another issue. You are
> > right... hams are just trying to reinvent the wheel.
>
>
> Right, not a lot has been published on this as it was all done sort
> of under the table away from the FCC.
>
>
> >
> > Later... Jim VE7RF
> >
> >
> > > --Toll_Free
> > >
> >
>
>
> Best,
>
> Will
>
Yahoo! Groups Links
|
I have a couple alternator companies quoting a 48 volt
alternator (54V) at 100 amps for my pickup.? I figure a couple 24 v truck
batteries in series in a bed mounted battery box with a custom remote mounted
amp.? I’ll build up a couple 50V amplifier modules.? I think
the CBer’s are right, just add an electrical system for what you think
you need… Maybe I can get away from the 750MCM battery cables that way…..
?
BOB DD
?
toggle quoted message
Show quoted text
From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of PA3DUV
Sent: Wednesday, January 10, 2007
9:09 AM
To: ham_amplifiers@...
Subject: [Norton AntiSpam] Re:
[ham_amplifiers] Re:hi power mobile
?
After reading all the post on this subject I will finish the
power supply as follows:
8 x 2 volt 230 Ah cells feeding the amplifier stack
16 volt 3 stage charger, input voltage 230 V AC
12 VDC => 230 VAC sine wave inverter to supply a limited
230 AC?for the charger ?while driving
an external 230 VAC connector on my trailer hitch so I can
charge the batteries when the car is on the driveway
A better alternative would be to install a second 16 volt DC
alternator, but there is simply no space for a second alternator.
----- Original Message -----
Sent: Wednesday, January
10, 2007 2:00 AM
Subject: [ham_amplifiers]
Re:hi power mobile
--- In ham_amplifiers@yahoogroups.com,
"pentalab" ...>
wrote:
>
> --- In ham_amplifiers@yahoogroups.com,
1800 Toll Free
> > wrote:
> >
> > It's kind of funny watching the thread about the mobile
amplifiers
> and
> > voltage requirements.
>
> ##### I have zero experience with it. I was just waiting for
you
> to come out of the wood work.... since I knew you guys had this
down
> pat... and was all old news. The deep cycle communications
> batteries work pretty good.
Right now, they're running those yellow top batteries with the spiral
cells. They claim these to be the best. Also, there's really no limit
to the batteries that you parallel together to get the power required
you need. The more batteries, the longer you can run. I've seen the
big 24V batteries used in diesel rigs too ran in these set ups. The
ones you want have the largest amp-hour ratings.
>
> ### I also read in an old QST... where they would use 2 x
> batteries in series.... like those used in golf carts..... but one
> was 6 V... and the other was 8 V. [didn't even know u could get
> deep cycle batteries... big ones... in 6 + 8 V ] Then ur car
> regulator would charge em to 14 .3 V..... then with engine OFF....
> ur small
706-mk-2-G would last way longer. That setup was also
> used in some Field day event's.
>
>
>
>
> > They use a charging system consisting of a 24 volt alternator,
and
> run
> > parallel / series combos of standard car batteries (or standard
> and deep
> > cycle, if they are smart) to have a 24 volt electric system.
One
> > alternator, and a pair of batteries will power quite a large
> system, as
>
> ### Don't some of em use train alternator's ??? Think they
> were split stator, dual rotor.... or split rotor, dual stator...
> made by Neville Leece.... at 1000 A per stator ?? Or was this
> for the tube setups ??
They'll use like 6 of the Leece Neville alternators under the hood to
power the big solid state amps. Some have used generators that can
provide 115/230 Vac too ran off the belt.
>
> ### I still haven't seen any detailed website on this hi power
> mobile stuff. Trying to generate the power is a huge project in
> itself. RFI, etc... Rf decks... is another issue. You are
> right... hams are just trying to reinvent the wheel.
Right, not a lot has been published on this as it was all done sort
of under the table away from the FCC.
>
> Later... Jim VE7RF
>
>
> > --Toll_Free
> >
>
Best,
Will
|
Will, Thanks for the input.
After reading all the post on this subject I will finish the power
supply as follows: 8 x 2 volt 230 Ah cells feeding the amplifier stack 16 volt 3 stage charger, input voltage 230 V AC 12 VDC => 230 VAC sine wave inverter to supply a limited 230 AC for the
charger while driving an external 230 VAC connector on my trailer hitch so I can charge the
batteries when the car is on the driveway A better alternative would be to install a second 16 volt DC alternator,
but there is simply no space for a second alternator. Cheers, Dick
PA3DUV Your best bet would be to get a dual output alternator, my friend. No matter what the car, the car stereo manufacturers make a dual output high current alternator. 100 amps is easy to get... 150 amps in almost any case style alternator. 200 and 225 amps are also sizes that most of the aftermarket audio manufacturers build. You can get 250 amps out of pheonix gold alternators. 300A leece neville. Rockford Fosgate makes a big alternator that fits in our "import" cars here. What you need has been done, by the car stereo crowd years ago, you just need to do a little bit of lookin around before you spend the hard earned dollars :)
|
In the
past and maybe still, 27 MHz was used in diathermy machines.
Effect????
?
David
KC2JD
?
toggle quoted message
Show quoted text
There is very little tissue heating at HF.
As you start passing
through Vhf to UHF you have severe issues. Some very
serious tissue effects
can happen at 432. My 432 amp can generate 2KW out.
With big antennas at
those frequencies ERP's in the mega watt range are
possible at ham power
levels.
The original microwave ovens ran around 900MHz well there's
another ham band
too.
You have more problems stopping pacemakers at
HF. I wonder if there could
be any liability at a stop sign if the person
in the car next to you keeled
over because you were trying to work the
7Alpha on 20 meters from the car?
At the old WB0DRL VHF/UHF contest
station they tuned the amps with microwave
leakage detectors, you know the
tool for testing ovens. All the stations
had them. The shack was RF tight,
however when the door was opened the
detectors would all start banging off
the pegs to the CW. Everybody would
scream "Shut that door"
I
declare Ham Radio is completely safe. What? (Battle Cry heard from the
LT
as you charge the enemy with only a knife in your teeth) YOU WANT TO
LIVE
FOREVER?
BOB DD
-----Original Message-----
From: ham_amplifiers@yahoogroups.com
[mailto:ham_amplifiers@yahoogroups.com]
On
Behalf Of badgerscreek
Sent: Wednesday, January 10, 2007 5:34 AM
To: ham_amplifiers@yahoogroups.com
Subject:
[ham_amplifiers] Re:hi power mobile
I think those Yellow Top Batteries
are called Optima Batteries?
I dont know why nobody is concerned about
having their brains so
close to the antenna? I mean sitting in the near
field of the antenna
running 1 or more kilowatts at the higher frequencies
would have me
worried. Maybe the adrenalin rush is more potent than
worrying about
your health, or maybe theres no
danger?
Greg
--- In ham_amplifiers@yahoogroups.com,
"craxd" wrote:
>
> --- In ham_amplifiers@yahoogroups.com,
"pentalab" >
> wrote:
> >
> >
--- In ham_amplifiers@yahoogroups.com,
1800 Toll Free
> > > wrote:
> >
>
> > > It's kind of funny watching the thread about the mobile
> amplifiers
> > and
> > > voltage
requirements.
> >
> > ##### I have zero experience with it.
I was just waiting for
> you
> > to come out of the wood
work.... since I knew you guys had this
> down
> > pat... and
was all old news. The deep cycle communications
> > batteries work
pretty good.
>
>
> Right now, they're running those yellow
top batteries with the spiral
> cells. They claim these to be the best.
Also, there's really no limit
> to the batteries that you parallel
together to get the power required
> you need. The more batteries, the
longer you can run. I've seen the
> big 24V batteries used in diesel
rigs too ran in these set ups. The
> ones you want have the largest
amp-hour ratings.
>
>
> >
> > ### I also read
in an old QST... where they would use 2 x
> > batteries in
series.... like those used in golf carts..... but one
> > was 6 V...
and the other was 8 V. [didn't even know u could get
> > deep cycle
batteries... big ones... in 6 + 8 V ] Then ur car
> > regulator
would charge em to 14 .3 V.... then with engine OFF....
> > ur
small 706-mk-2-G would last way longer. That setup was also
> > used
in some Field day event's.
> >
> >
> >
>
>
> > > They use a charging system consisting of a 24 volt
alternator,
> and
> > run
> > > parallel /
series combos of standard car batteries (or standard
> > and deep
> > > cycle, if they are smart) to have a 24 volt electric
system.
> One
> > > alternator, and a pair of batteries
will power quite a large
> > system, as
> >
> >
### Don't some of em use train alternator's ??? Think they
> > were
split stator, dual rotor.... or split rotor, dual stator...
> > made
by Neville Leece.... at 1000 A per stator ?? Or was this
> > for the
tube setups ??
>
>
> They'll use like 6 of the Leece
Neville alternators under the hood to
> power the big solid state amps.
Some have used generators that can
> provide 115/230 Vac too ran off
the belt.
>
>
> >
> > ### I still haven't
seen any detailed website on this hi power
> > mobile stuff. Trying
to generate the power is a huge project in
> > itself. RFI, etc...
Rf decks... is another issue. You are
> > right... hams are just
trying to reinvent the wheel.
>
>
> Right, not a lot has
been published on this as it was all done sort
> of under the table
away from the FCC.
>
>
> >
> > Later... Jim
VE7RF
> >
> >
> > > --Toll_Free
> >
>
> >
>
>
> Best,
>
>
Will
>
Yahoo! Groups Links
|
