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dec-93.txt



  Date: 12-01-93  00:01
  From: Dave Lyle       
    To: Richard Quick      
  Subj: 1,000,000Kva Tesla Coil
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RQ>coil "converts" the base current into a voltage at the other
RQ>end. Since this voltage rises as you go higher and higher up
RQ>the coil, and reaches it's peak at the top; Tesla was able to
RQ>determine the voltage at the top of the coil is the first 1/4
RQ>wave voltage peak of the RF current fed into the bottom.

Richard, GREAT series of articles here.  Just a quick question
here.  First, I understand what is happening as far as the 1/4
wave length is concerned. I relate this to transmission line
theory, where the VSWR is approaching infinity.  My question
though, is..how does the coil excite at other odd multiples of
1/4 wave, i.e. 3/4, 5/4 wave?  I suspect it would be more lossy,
but what, if any, benefits might be derived by operating at the
higher frequency?   Dave

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  Date: 06 Dec 93  13:12:00
  From: Richard Quick                                
    To: Dave Lyle                                    
  Subj: 10KVA Tesla Coil
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 DL> Richard,
 DL> GREAT series of articles here.  

Thanks! Another vote of confidence!

 DL> Just a quick question here. First, I understand what is      
 DL> happening as far as the 1/4 wave length is concerned. I      
 DL> relate this to transmission line theory, where the VSWR is
 DL> approaching infinity. 

You are correct in this relation. Transmission line theory does
apply to Tesla secondaries.

 DL> My question though, is.. how does the coil excite at other   
 DL> odd multiples of 1/4 wave, i.e. 3/4, 5/4 wave? I suspect it  
 DL> would be more lossy., but what, if any, benefits might be    
 DL> derived by operating at the higher frequency?

Coils that are excited or driven to higher harmonics (over 1/4
wave) break down prior to the top turns. For instance a coil
driven to 3/4 wave resonance would still break down at the 1/4
wave point of the winding. This problem is commonly seen on coils
that are overdriven or overcoupled, and I cannot imagine any way
to insulate against this breakdown. Higher harmonics CAN be
reached by using two or more coils driven from the same tank
circuit or by placing the primary in the center of a single coil.
For instance a 1/2 wave system could be built using two coils, or
driving one coil from the center producing two 1/4 wave peaks,
one at either end.

The trick to efficiency is to excite at a LOWER harmonic (below
1/4 wave), ie: 1/8th wave, 1/16 wave, or 1/32 wave. These lower
harmonics are high in current, and lower in voltage. Loss is
reduced because the lower voltage leaks less, and the energy of
the wave is a product of both current and voltage. The 1/8th wave 
harmonic appears to be the most efficient.

Now remember that we have not changed the frequency. The system
frequency may remain the same, we are simply tapping the energy
further back in the wave form. Tesla was able to force the
secondary into these lower harmonics by the addition of the extra
coil to the system, then reducing the number of turns in the
secondary until it was 1/8th wave resonate. Current and voltage
were then fed to the base of the extra coil resonator.

The advantages of using the extra coil, and tapping the secondary
energy at a lower harmonic are many: Coupling between primary and
secondary may be tightened up considerably, driving more energy
through the system; the 1/8th wave output of the secondary
contains 70% of the wave energy as opposed to the 50% obtained in
1/4 wave output; there is much less voltage stress on the
secondary which reduces the incident of breakdown and "splitting"
(parasitic 1/4 wave peaks); current is removed from the secondary
by transmission line to the extra coil, unloading the secondary
for more input (allows higher break rates in the gap = greater
throughput) and placing the main system VSWR in the uncoupled end
resonator (extra coil); impedance, resistance, and distributed
capacitance are also reduced with proper design and construction.

This production of a lower harmonic from the secondary by adding
the extra coil to the system is a true breakthrough in Tesla
power processing. This is the three coil Tesla Magnifier as Tesla
developed to industrial proportions in Colorado Springs, and may
be scaled back for very efficient "basement" systems. I have seen
Magnifiers producing 100"+ arcs at 4100 watts input power, and
have myself hit 72" with inputs around 2500 watts. I see a real
gain of 40% in spark length for input power with this system.

Thank you for your input on transmission line theory and your
question. I hope I have given a reasonable and satisfactory
response. If you have any other questions or comments I would be
more than happy to reply to them.

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  Date: 06 Dec 93  11:17:00
  From: Richard Quick                                
    To: Joseph Freivald                              
  Subj: 10KVA Tesla Coil
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 JF> For those of us who are wanna bees, What's a Tesla coil, and 
 JF> why does it get at least 10 posts per day?

A Tesla Coil is an air core, RF resonate, transformer. It is a
very efficient source of very high voltage RF energy. If it
weren't for the problem I am having with my ASCII character set I
would give you a wiring diagram.

Basically you take a high voltage pulse discharging capacitor and
connect it to a large heavy coil. The cap is charged with a high
voltage power supply (neon sign xfrmr, potential xfrmr, or power
distribution xfrmr run backwards). The circuit consisting of the
cap and coil is excited by discharging the cap through a spark
gap. This way current of hundreds of amps at thousands of volts 
oscillate through the coil. Frequency of oscillation is dependant
on the number of turns in the coil and the size of the cap.
This is the basis of the Tesla Tank circuit.

The secondary coil or "Tesla coil" is a hollow form with several
hundred turns of wire. This coil has a natural RF resonate
frequency based primarily on the length of wire used in the
winding. The tank circuit frequency is made to match the
secondary natural frequency by tuning, changing the number of
turns in the heavy primary coil or changing the value of the
pulse discharging capacitor. When the tank circuit frequency is
matched to the secondary frequency, and the coils are placed in
close proximity, energy is exchanged and transformed.

RF voltages in the megavolts can be achieved with very high
efficiency. The tank circuit literally converts line current into
a series of rapid pulse discharges with peak powers in the
megawatt range. A simple coil setup is capable of producing more
or less continuous spark discharges several feet in length, or
longer. 

I cannot say why there are so many posts on the subject, except
that the topic is interesting and I have had more than a few
requests for information on these systems. I have sent out a few
video tapes with some of the work I have done, and it has greatly
accelerated the interest. My video features a coil system I built
operating with 10,000 watts input power, generating peak powers
of 22 megawatts, with a discharge voltage of between 3-5
megavolts (or more). The system is able to produce arcs of
synthetic lightning that strike out up to 15 feet.

I hope this answers your question. If you need any additional
information, or have other questions, please feel free to post on
this topic.

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  Date: 06 Dec 93  11:33:00
  From: Richard Quick                                
    To: Dave Halliday                                
  Subj: 10KVA Tesla Coil
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 RQ>A tank circuit with a small capacitor, and a large primary
   >inductance, will reach down to the lower frequencies of       
   >operation. A tank circuit of this design will use less power, 
   >and therefore require a smaller step up xfrmr. The capacitor  
   >will be smaller, which further reduces the cost of the        
   >system.

 DH> Makes a lot of sense!  

Efficiency, efficiency... Put every watt into the discharge!
 
 RQ>So to give some advice to my friend Dave Halliday, who is
   >building a 6" secondary coil sometime in the near future,
   >plan on winding a primary coil from a conductor material that 
   >I have listed above, and use a conductor length of around 75  
   >feet. Your primary should end up about as wide as, or wider,  
   >than your secondary is tall.

 DH> Got it!  I was thinking of using some 3/8ths refrigeration   
   >tubing but since the surface area is important, I'll probably 
   >get a reel of 3/4ths or 1/2" tubing ( gotta check on pricing  
   >first )

With a 6" secondary coil that is 24" high, 3/8" soft copper water
pipe is perfect. My big coil uses 1/2" pipe and only gets
slightly warm on the first and second turns after a five minute
full power run. Balance the diameter of the pipe to the length of
the primary conductor. 50' conductor use 1/4" pipe, 75' conductor
use 3/8" pipe, 100' conductor use 1/2" pipe. When in doubt use
the next size up.

 DH> Trade some videos / photos once I get something to show.

COOL!

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  Date: 06 Dec 93  12:45:00
  From: Richard Quick                                
    To: Dave Halliday                                
  Subj: 10KVA Tesla Coil
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 DH> There is a local park that is situated on Lake Washington    
 DH> near where I live, I have been toying with the idea of
 DH> firing the coil off there, maybe out on one of the boat      
 DH> docks. Drop a bunch of Aluminum flashing over into the water 
 DH> for the ground.

 DH> Could be kind of fun!

I have fired and grounded off of water grounds exactly as you are
thinking. They work great!

Good Luck! I hope to see a spark shot or two soon. Bring the
camcorder, and a 35 mm, and a few friends.

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  Date: 06 Dec 93  13:11:00
  From: Richard Quick                                
    To: All                                          
  Subj: 10KVA Tesla Coil
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OK, People who are interested in the TESLA VIDEO have not, are
not, and will not be disappointed.

I will send a full 2 hour SP recorded, one off master, VHS tape
with sections showing my big coil literally burning up the back
driveway and striking everything within 11 feet (arcs as big
around as my leg on some strikes).

You must send $10.00, a self addressed postage pre-paid return
mailer, and a blank, high quality VHS tape.

                    Richard T. Quick II
                    10028 Manchester Rd.
                    Suite 253
                    Glendale, MO  63122  USA

Tapes are sent out within 48 hours from receipt of your package,
there is no monkey business. The video is instructive: it shows
several coil systems in operation, details on the power control
cabinet, wiring, tuning and firing as well as sections on spark
gaps, RF filter chokes, etc. I also fire my "pole pig" utility
power distribution transformer in a Jacob's Ladder at 8000 watts
with 20,000 volts across the rails.

This tape is my cutting edge 1/4 wave Tesla work, and involves
lots of high voltage set ups and demonstrations. Due to the
nature of the work covered on the video: I CANNOT BE RESPONSIBLE
FOR THE SAFETY OF ANYONE ATTEMPTING TO REPRODUCE ANY OF THE
SYSTEMS OR EXPERIMENTS FEATURED ON THE VIDEO!!!!

I am more than happy to answer any questions or respond to
comments in this area on anything covered on the video.
I will also trade tapes even with people who are engaged in
similar or other work of interest: Tesla coils or other high
voltage equipment in action, rail guns, laser setups, taser guns,
particle accelerators, capacitive discharge machines, etc.

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  Date: 12-10-93  23:51
  From: Dave Lyle                    
    To: Richard Quick                    
  Subj: 10Kva Tesla Coil
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RQ> I have a normal Tesla secondary that resonates at about 200
RQ> kHz with a discharge terminal. When this coil is placed in a
RQ> primary and critically coupled, it will fire when the tank
RQ> circuit is tuned to 200 kHz. No problems here, this is a 
RQ> normal 1/4 wave system. The tank circuit oscillates at 200
RQ> kHz, the secondary coil with discharger resonates at 200 kHz,
RQ> and the output from the system is the 1/4 wave peak of a 200
RQ> kHz signal.

RQ> Now we remove the secondary from the primary and replace the
RQ> secondary with a coil that is 1/4 wave resonate at 400 kHz.

Hi Richard,

I was actually wondering what would be the effect of going the
opposite way.

What if you removed the _primary_ and replaced it with one that
resonated at 600 Khz.  Now the secondary would be resonate
at 3/4 wave, and the voltage/current distribution would be:

At the base.........................Current peak, Voltage null
At the 1/4 wave point
   (1/3 of the way up the coil).....Voltage peak, Current null
At the 1/2 wave point
   (2/3 of the way up the coil).....Current peak, Voltage null
At the 3/4 wave point
    (Top of coil)...................Voltage peak, Current null

I suppose you would have trouble preventing a breakdown at the
1/4 wave (1/3 of coil) point, but would there be any advantages
to the higher frequency operation?

 414-476-8468 (1:154/100)

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  Date: 12-12-93  12:12
  From: Robert Taylor               
    To: Richard Quick               
  Subj: Re: 10KVA Tesla Coil
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Wanted to drop you a line & see if you got my post about a month
ago on the book that Barnes&Noble has out called *The Inventions,
Research, and Writings of Nikola Tesla*.

Got a new catalog from them the other day & saw that their price
had gone down to about $10.  Good book w/ a lot of the heavier
technical stuff (including original schematics).

Definitely worth a look.

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  Date: 14 Dec 93  12:19:00
  From: Richard Quick                                
    To: Dave Lyle                                    
  Subj: 10Kva Tesla Coil
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 RQ>Now we remove the secondary from the primary and replace the
 RQ>secondary with a coil that is 1/4 wave resonate at 400 kHz.

 DL> I was actually wondering what would be the effect of going   
 DL> the opposite way.

 DL> What if you removed the _primary_ and replaced it with one   
 DL> that resonated at 600 Khz.  Now the secondary would be       
 DL> resonate at 3/4 wave, and the voltage/current distribution   
 DL> would be:

> At the base.........................Current peak, Voltage null
> At the 1/4 wave point
> (1/3 of the way up the coil).....Voltage peak, Current null
> At the 1/2 wave point
> (2/3 of the way up the coil).....Current peak, Voltage null
> At the 3/4 wave point
> (Top of coil)...................Voltage peak, Current null

 DL> I suppose you would have trouble preventing a breakdown at   
 DL> the 1/4 wave (1/3 of coil) point,

Trouble would be a mild word for it. The 1/4 wave voltage peak
appearing in the windings would destroy the coil in short order.
RF voltages in these frequencies just don't understand what
"insulation" is. I have not found any practical material or
construction technique that would contain the voltage of a solid
1/4 wave voltage peak that appears in the coil windings. Plate
glass, 1/4" thick polyethylene, etc. are invisible to this
discharge, and the energy passes right through it virtually
unimpeded. Mineral oil is the best insulator for this particular
energy, but there is insufficient space between turns on the coil
for sufficient breakdown protection. Even if there was enough
room between turns, then you have problems with the coil form
breaking down.

I have done experiments with coils in which the same basic end
result was achieved by bottom feeding an extra coil with current
that resulted in higher harmonic resonances of the extra coil
(such as the 3/4 wave harmonic you charted above). When the coil
was fired, sparks and corona came flying out of about a dozen
turns in the coil. Those turns where spark and corona appeared,
corresponded to the 1/4 wave peak. But there was no way to
contain it. The sparks broke down the windings, scored, then
carbonized the coil form . The coil suffered irreparable damage
and had to be scrapped. Similar incidents with other systems
where energy densities were high resulted with the spark from 1/4
wave peaks in the winding blowing holes through the coil form.
Again the coil was a complete loss and had to be scrapped.

In addition to the breakdown, the remaining turns further up the
coil had no energy at all to speak of. Why? All the energy in the
system was lost to spark and corona leakage at the 1/4 wave
breakdown point, insufficient energy remained in the coil
windings above the breakdown to do anything.

 DL> would there be any advantages to the higher frequency        
 DL> operation?

None that I can think of. This model represents a very high loss
situation. 1/4 wave voltage peaks represent the final output
point in a coil system. There is no way to process the energy in
wire to any point above 1/4 wave in a single coil without
tremendous losses.

However when you go to two or more coils, where you are working
with more than one output terminal, it is possible to achieve 3/4
wave signal processing. This requires a pair of 1/8 wave driver
coils, two primaries run in series off the same tank circuit, and
two extra coils. Your outputs from the extra coils are still 1/4
wave with the peaks on the terminals, but taken as a whole the
system does efficiently process a 3/4 wave signal. This system
would be adding up lower harmonics (two 1/8th wave outputs, with
two 1/4 wave outputs) to get to efficient 3/4 wave signal
processing. This system would be unique in that it may not
require a ground, as the two tuned sets of coils could "beat" off
of each other; in other words the nul voltage current output from
the base of one 1/8 wave driver coil could be fed into the base
wire of the second driver. This system would require that the
series run primaries, and the drivers and extra coils be wound in
opposite directions to achieve phase differential. The base wire
current output of one coil becomes added input to the base of
another. 

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  Date: 14 Dec 93  12:33:00
  From: Richard Quick                                
    To: Robert Taylor                                
  Subj: Re: 10KVA Tesla Coil
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 -=> SEZ  Robert Taylor to Richard Quick <=-

 RT> Wanted to drop you a line & see if you got my post about a   
 RT> month ago on the  book that Barnes&Noble has out called *The 
 RT> Inventions, Research, and Writings  of Nikola Tesla*.

Yes I did. I take it then you missed my reply.

I own a copy, and a copy of nearly everything else worthy of note
on the subject. I have posted a bibliography for source material
on his more advanced work.

The book you mention is drawn from his public lectures and other
"public domain" material. Things really start getting good when
you access sources of material he produced that were never
intended to become public. This private material, when combined
with his patents and patent applications, reveals much larger
plans.

Thank for checking up, and the book does make very interesting
reading. It covers some of his early work in good detail.

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  Date: 12-14-93  14:23
  From: Dave Halliday                           
    To: Richard Quick                           
  Subj: 10KVA Tesla Coil
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RQ>Look forward to seeing some video/photos of your coiling work
  >soon. BTW did you really decide to lengthen the 6" coil form   
  >from 24" to 30" in height? I would think this would require    
  >more than the 1500' of magnet wire you had earmarked for this  
  >project.

I was thinking of 30" all along.  That stays within the 1:5
aspect ratio limit.  The thickness of the wire that I got will
allow for 940 or so turns in 30" of length which works out right
at 1500' feet of wire.

RQ>Also, I am seeing posts that you have quoted from others, but  
  >I am not seeing the original posts here....

RQ>This looks to be a network problem, unless these people are
  >posting to you locally.... I wonder what is going on.

I had been using another BBS for the FIDO messages and they were
having some problems with missing messages.  I will be using
SLUG-BBS from now on until I get my Planet Connect dish up and
running.  It is sitting in the store right now but I need to get
on the roof and cut a hole through the ceiling for the feed-
through and of course ( being Seattle ) it is raining pretty much
continuously...  Maybe August if I am lucky  <grin>

Anyway, when the dish gets set up, I will start my own FIDO feed
to my BBS.

RQ>I sent you a post last week mentioning that I saw you had made 
  >a local logon here to the SLUG BBS, we narrowly missed a chat. 
  >How long have you been calling locally? If you get the chance  
  >since it appears you have a high speed modem you can grab the  
  >thread here if you have any network problems. This board has   
  >nearly all of my original posts in this conference still       
  >available.

I already grabbed them - I had called a few times from home but
the modem I am using there is an older one and it sometimes
hangs.  I will be calling from the store now.

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  Date: 12-14-93  14:30
  From: Dave Halliday                       
    To: Brian Carling                        
  Subj: 10KVA Tesla Coil
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BC>thanks for the info. I am going to see what I can find at the
  >local library also.

Although I have not really researched Tesla's life all that much,
from what I gather, he kept critical stuff from his patent
applications because he had been screwed by Marconi and others. 
You need to read between the lines.

DH> You could scale down the design but I feel that the amount of
DH> time and money involved would be about the same regardless of
DH> what size coil you are building so why not go for a bigger
DH> one.

BC> No, I want to build the BIG one!

How big?

DH> The one I am building is 6" diameter, 30" tall and is powered
DH> by a bank of four neon sign transformers.

BC> That doesn't sound too huge to construct...

It struck me as a nice size - large enough to produce nice 5'
arcs but small enough as not to overwhelm my workshop or my
budget.

BC> Do you connect the neon sign transformers in series or what?

A combination - the transformers are 12kV at 30mA so I will get
24kV at 60mA by using four of them.

DH> Down the road, I would like to experiment with a "pocket" 
DH> coil or a tabletop model but you do need a very very good 
DH> ground regardless of the size so this isn't something that
DH> you could take somewhere and casually set it up and expect to
DH> get good results.

BC> Why can't the one you describe be a "table-top" model?
  > 6" around by 30" tall would fit on most tables!

Yeah but I was thinking about one that was maybe 3" dia and 12"
tall.

That would be impressive if it threw out foot-long arcs and from
what all of the other designs of this type do, the arcs are
several times longer than the length of the primary.

Imagine something sitting on the table, a foot tall and two feet
or so in diameter ( the flat primary coil ) throwing off two foot
long arcs!

DH> Anyway, keep tuned to this conference and I will be letting
DH> people know how things are progressing!

BC> I'll watch eagerly!

Hey - start planing something!  Get some neon transformers, some
stuff to make the capacitors and a bunch of magnet wire and start
building!

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  Date: 12-15-93  11:04
  From: Richard Quick                   
    To: Dave Halliday                      
  Subj: 10KVA Tesla Coil
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 RQ>Good Luck! I hope to see a spark shot or two soon. Bring the
   >camcorder, and a 35 mm, and a few friends.

 DH> I am going out of town for fifteen days over the holidays
 DH> but I should have something in a month or so after that.
 DH> Have a lot of the raw materials - stuff for the capacitor.
 DH> Need to get the neon transformers and actually wind the coil
 DH> and build the base to hold the primary. Things have been
 DH> extremely busy at the store so I haven't had too much
 DH> "spare time" but January has always been pretty slow.

Great, then at least you are in the planning stage and are
organizing yourself for the various constructions.

 DH> Anyway, I am now getting the feed directly from SLUG-BBS so
 DH> there should be no missing messages.

And no delay!!!

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
  Date: 12-15-93  12:11
  From: Richard Quick                     
    To: Dave Halliday                      
  Subj: 10KVA Tesla Coil
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
 -=> SEZ  Dave Halliday to Richard Quick <=-

 RQ>Thank you Dave for sending the magazine with the article on
   >the spark gap transmitters. It was interesting, but full of
   >miscrediting. The author chose in many instances to detail
   >the worst systems of the era.

 DH> I thought you would get a kick out of it.  I had intended
 DH> you to keep the magazine - that was why there was just the
 DH> return mailer for the disk.  If you want, I can pop it in
 DH> the mail again.

No need. I copied everything that I wanted.

 DH> Anyway - I figured you would have some fun with the article.
 DH> I have not made any major study of Tesla's life but what I
 DH> have seen ( Man out of Time by Cheney (sp?) plus a couple
 DH> other articles ) makes me realize that he is very much an
 DH> un-sung hero of electronics.

He was THE electrical genius of his time.

 >I just find it galling that he would go through such efforts in
 >accuracy this area and would only mention Tesla's name once.

 DH> Yeah - it is like he is just copying the "party line" of the
 DH> people who claimed to "develop" the equipment without doing
 DH> any research on his part...

Exactly. Tesla developed and experimented with every type system
mentioned in the article before the people credited for these
systems.

 >The gaps would not quench well at these power levels, and the
 >short primary conductor does not provide sharp tune, good
 >coupling coefficients or energy transfers. Tesla's systems of
 >this era were much much more advanced.

 DH> The three turn primary also caught my eye.  Plus the
 DH> capacitance was probably huge and lossy - oil filled wooden
 DH> boxes...

Yeah, the signal generated by this system would have been highly
erratic. The pulses would have been very intense due to the
capacitor size, but the output had to be a far cry from being a
"smooth" powerful signal. Tesla on the other hand was using a
tiny capacitance in a "balanced" tank circuit with very close
coupling, and extremely fast quenching, ultra high speed gaps.

He processed only 250 kVA (50 kVA less input power than the large
Marconi xmittr) in Colorado Springs, but his output was CW,
frequency stable, beat free, RF signal. His power processing
efficiency was over 70% from the supply line to the antenna mast.
His antenna current was a modest 1100 rms amps, with a peak power
in excess of 10 gigawatts. Not bad for a guy in 1900 with a
shoestring budget and salt water/glass caps.

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
  Date: 12-15-93  13:28
  From: Richard Quick                  
    To: Dave Halliday          
  Subj: 10KVA Tesla Coil
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
 -=> SEZ  Dave Halliday to Brian Carling <=-

 BC>Do you connect the neon sign transformers in series or what?

 DH> A combination - the transformers are 12kV at 30mA so I will
 DH> get 24kV at 60mA by using four of them.

Nope, won't work. Each secondary coil in the neon xfrmr is
grounded to the core. This setup will not allow the secondaries
to be placed in series. Other type xfrmrs may be placed in
series, such as plate, potential, and pig xfrmrs, but not neons.

The secondaries may be placed in parallel for higher currents,
but you are voltage limited. This is OK really because you will
have trouble making or finding caps that will hold up to 24
kvac pulse.

The primaries on neons are not grounded. The primaries may be
run in parallel, so you may gang up as many as you want at 120
volts as long as your circuit will stand up to the load (which
may be surprisingly high if you don't use pfc capacitance).

However for anything larger than 1.5 kVA you will most likely be
looking hard at 240 volt operation to reduce the current load. In
this case you may take two neons of the same rating, place the
primaries in series, and throw 240 across the two units. The
secondaries are all parallel wired to the high voltage buss,
regardless of the arrangement of the primaries. This way really
large power supplies may be built up slowly, by simply adding
pairs of neons to the bank. I have run up to 12 neons (6 pairs
wired for 240 volt operation) for power supplies in excess of 4
kVA for medium sized coil systems.

Phasing is important in running banks of neons. Not all neons are
wired in the same direction. If the primary or secondary coils
are reverse wired on some units, they will cancel out other
units. A little time may be required to make sure that all of the
neons are wired in phase. Nothing special is required to do this,
just identify the out of phase unit, and reverse the line power
connections, or reverse the secondary connection to the HV buss.

You should also make sure to run any HV power supply off a
variable autotransformer (variac). This way output voltage to the
experiment may be controlled smoothly.

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ 
  Date: 16 Dec 93  17:35:00
  From: Richard Quick                                
    To: Dave Halliday                                
  Subj: 10KVA Tesla Coil
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Again referring to Tesla:

 DH> Yeah - I heard that he was sitting on a bench somewhere and  
 DH> the motor came into his head completely formed.  Just        
 DH> sitting there in his imagination, running smoothly...

This is apparently true, Tesla told the story on more than one
occasion. Many other notables of genius status have said their
greatest ideas came in similar fashion, or in dreams; but few
were as prolific as Tesla.

It seems that ideas like this came to him very frequently over a
number of years. He complained more than once that it was simply
impossible for him to act on all of them. Tesla read Edison's
quip that invention was "1% inspiration and 99% perspiration" and
remarked that the inverse was in fact the truth. He stated that
he was able to operate sophisticated mechanical and electrical
devices in his head to determine feasibility prior to drawing or
constructing the actual device. He followed this statement up by
saying that he never built a device that did not operate as
anticipated.

In his later years, after failing to fund the Wardenclyff
transmitter to completion, he was unable to maintain a
laboratory. He did not stop inventing however. He set his MIND to
work building, testing, and operating equipment. The result of
his purely mental efforts were designs for such devices as
particle beam weapons. This mental work came into tangible
existence in the form of drawings for such components as the open
ended vacuum tube (one end open to STP) for generating high
energy particle beams. 

It is one of the true crimes against humanity that he was so
misunderstood that even a small lab could not be furnished to
allow him practical creative outlets, though much blame may be
laid to him for his ignorance of financial affairs, and his
refusal to retain a business manager to see to those affairs.
He spent money like water, money having no real value to him. He
allowed people to purchase valuable patents outright instead of
insisting on long term royalty agreements in addition to the lump
sum payments, which would have insured some future income. Had he
been monetarily wiser, he would not have died penniless, and many
more ideas could have seen commercial application; even if the
final marketing was done by others.

Have a good vacation, I look forward to hearing from you upon
your return.

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
  Date: 12-19-93  11:08
  From: Robert Taylor                
    To: Richard Quick                  
  Subj: Re: 10KVA Tesla Coil
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
 -=> Quoting Richard Quick to Robert Taylor <=-

 RQ> Yes I did. I take it then you missed my reply.

Looks like you're right.  I think the BBS that I picked you up on
was having some problems around that time, so end of mystery.

 RQ> I own a copy, and a copy of nearly everything else worthy of 
 RQ> note on the subject. 

Guess I shoulda known better on that one!  You must have one
heckuva Tesla library.

 RQ> intended to become public. This private material, when       
 RQ> combined with his patents and patent applications, reveals   
 RQ> much larger plans.

I can only imagine how interesting some of this material must be. 
I was aware of some Hungarian translation of his private papers
was out there, but have never seen a copy of same.

Just out of curiosity, are you familiar with anything regarding
Tesla's connection with the "project invisibility" & the U.S.S.
Eldridge?  Ran across something that connected him with the
project, but everything that I've seen is vague.  An impression
was left that he may have had something to do with the building
of the alleged field-generator.

BTW--did catch your reply on my post about Ken Strickfadden.  His
work always amazed me.  Seasons Greetings & Happy Holidays.

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
  Date: 12-21-93  14:03
  From: Richard Quick                            
    To: Robert Taylor                            
  Subj: 10KVA Tesla Coil
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Regarding: The Inventions, Writing, and Research of Nickola Tesla
available from Barnes & Noble Booksellers

 RQ> I own a copy, and a copy of nearly everything else worthy of
 RQ> note on the subject.

 RT> Guess I shoulda known better on that one!  You must have one
 RT> heckuva Tesla library.

Over 200 separate covers at this time. A lot of the material I
have read two, three, even four times looking for clues.

 RT> I can only imagine how interesting some of this material
 RT> must be. I was aware of some Hungarian translation of his
 RT> private papers was out there, but have never seen a copy of
 RT> same.

I believe the book you are referring to is the Colorado Springs
Notes, which were hand written in English in 1899-1900. These
papers and many others were processed by the Office of Alien
Affairs at the time of Tesla's death (though he was a full
citizen...). Tesla had no relatives in this country. Before his
death the Yugoslavian government had declared him a national hero
(while we were busy starving him). When the Yugoslavs found that
he was completely destitute, they set up a trust fund to see that
he received a monthly check to cover his food and rent. It was
all he had when he died. Since the Yugoslavian government was
taking responsibility for his care, the U.S. government declared
Yugoslavia the next of kin. The personal effects found in his
hotel room were pilfered (many valuable items were stolen), and
what remained were sent to Belgrade where they were placed in a
museum.

In the mid 1970's the curator of the Tesla Museum in Belgrade
cataloged all of the papers written by Tesla in Colorado Springs.
About this time "pilgrims" such as Robert Golka began showing up
at the museum to read the originals. The curator decided to
publish through NOLIT of Belgrade, and copies were made available
in the U.S. for around $45.00 for a beautiful gold leaf, leather
bound edition. Today my copy is worth over $100.00. The book has
reprints of most of the surviving photos Tesla took of the lab,
it's contents, and some of the experiments performed there.

It should be noted that Tesla was very proud of his U.S.
Citizenship. He spoke five languages fluently, but English was
his mother tongue. All of his patents, articles, and interviews
were conducted in English, and all of his notes were in English.

 RT> Just out of curiosity, are you familiar with anything
 RT> regarding Tesla's connection with the "project invisibility"
 RT> & the U.S.S. Eldridge?  Ran across something that connected
 RT> him with the project, but everything that I've seen is
 RT> vague. An impression was left that he may have had something
 RT> to do with the building of the alleged field-generator.

This area would most definitely fall under the protection of
National Security interests, and as such would be highly
classified if the project did in fact take place. I have never
seen any concrete proof of this project or Tesla's involvement.

But that does not stop the stories and conspiracy theories. I
have heard more than a few. I cannot say if any of this is worthy
of believing or not, as I base my information on facts not hear-
say. Nobody to my knowledge has presented verifiable facts on
this.

But it is a fact that to this day the U.S. government has a Top
Secret classified archive in Washington D.C. which contains the
bulk of papers Tesla wrote in his later years. Some of these
papers are believed to have originated from his hotel room, but
the bulk of these papers (many boxes) were removed by the Office
of Alien Affairs from his rented storage room. They were not
turned over to the Yugoslavian government because they were not
considered to be "personal effects". It is my understanding that
these papers concern Tesla's particle beam weapon plans, and more
likely than not the field generator plans if they do exist.

As I have stated, the existence of the archive has been
established, as well as the fact that many unpublished documents
written by Tesla reside there. The exact catalog of documents is
a mystery. It is interesting to note that 50 years after Tesla's
death, the U.S. government still considers these documents to be
of the gravest concern to national security.

Related filings under the Freedom of Information act has revealed
clues on some of these documents. It is a known fact that the
powerhead design for a coil driven particle beam weapon resides
there. This powerhead was a vacuum tube open to the air at one
end. Vacuum was maintained at one end of the tube by using a
vortex of compressed air, so the tube geometries are similar to
an aspirator pump. The tube contained a standard capacitive
discharge rail gun at the low pressure end which produced and
accelerated metal plasma. The main system energy was given to the
plasma from a large Magnifier system (believed) which provided
voltage to further accelerate the plasma to near light speeds
over a very short distance. I have seen reproductions of original
unpublished sketches that Tesla made of this powerhead that were
included with his papers sent to Belgrade, and brought to light
by one of the "pilgrims" returning in the late 1970's. I have no
doubt as to the authenticity of the information I saw, as
there was a representative of the museum in attendance when the
sketches were viewed and discussed, and the reproduction bore the
identical museum authenticity stamp that my published copy
of the Colorado Springs Notes bears.

Back to your subject of "project invisibility", I have heard
nothing but rumors. I heard a guy a couple of years back who
claimed to have seen Tesla at White Sands early in the war
working on a classified military project. This story could not be
verified, and the teller offered no proof. Good story though.

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
  Date: 08-18-93  20:50
  From: Richard Quick                             
    To: Terry Smith                                               
  Subj: Tesla Coils
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
High power lighthouse triodes are available from Vacuum Tube
Industries, Inc. 506 North Warren Ave., P.O. Box 2009, Brockton,
Massachusetts 02405-2009, U.S.A, tel 1-800-528-5014 outside MA.
New and reconditioned (I believe they can recondition most any
power tube). Xformers, water cooling recirculators, thyratron
SCR & sat. reactor control units, the works...

Prices are a little high, but if the builder were so inclined a
tube and supply xformer for a few hundred could be had, and the
rest can be matched and scrapped together for some mean tube
coilin.

If you fry a filament or puncture a plate they can patch'er right
up. Coils built from these type tubes tend to run about 400-450
khz, so the spark length is not much over three feet (only
three!), but the current in the discharge would be awesome.

Any thoughts?

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
  Date: 28 Dec 93  12:51:00
  From: Richard Quick                                
    To: All                                          
  Subj: 10KVA Tesla Coil
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Well I hope everyone had a happy holiday. I am now recovered
enough to post some more specific info on Magnifier construction
and operation. I have covered some general material on this
revolutionary Tesla coil system, but will now endeavor to throw
out some specific pointers for those of you who have an interest
in this much more efficient RF power processor.

As I have mentioned the Magnifier is a three coil system. The
primary is excited from a Tesla tank circuit, the secondary coil
is inductively coupled to the primary, and the extra coil is top
loaded on the secondary in such a fashion as to be uncoupled
completely from the primary/secondary "driver" coils. The extra
coil is base fed by transmission line, which can be anything from
Litz wire, copper pipe, or heavy DC transmission wire.

The keys to getting an efficient Magnifier setup in operation can
be listed fairly easily: Close coupling between primary and
secondary, good gap quenching, and proper impedances in the
secondary driver and the extra coil.

Coupling in Tesla magnifiers must be tight. Classic style
vertical helix primaries are very practical for use in Magnifier
systems, but heavy insulation between the coils must be used to
prevent flashover. The close coupling reduces somewhat the VSWR
in the driver secondary, and the 1/8th wave output contains
substantially less voltage than a normal 1/4 wave Tesla system,
but the close physical proximity between coils means flashover 
will be a problem. Use several layers of polyethylene plastic
around the secondary, and insulate the top primary turns with
heavy vinyl hose. It has come to my attention that tapping the
primary coil from the bottom turns, and heavily insulating the
top turns, reduces flashover. (now gee, why didn't I think of
that?)

Good gap quenching is a must. Because the coupling is so much
tighter in Magnifier systems, more strain is put on the main
system spark gap. If ever there was a need for exotic spark gap
systems this is it. Quench times must be low, low, low, in order
to trap the maximum energy into the secondary driver. An un-
quenched (closed) gap will allow energy in the secondary back
into the primary/tank circuit. This must be prevented. In
Colorado Springs, Tesla used a pair of air blast gaps in series
with a massive rotary. He kept pushing his line frequency higher
(he had a massive, variable speed alternator in the lab),
increased his break rate (up to 50,000 bps) and kept the energy
delivered per pulse down to a minimum. The reason he strove to
keep the energy per break down was to prevent overloading his
gaps. As energy per break (voltage * current) increases, quench
times decrease and efficiency in the Magnifier drop off. The
increase in the number of breaks per second allowed the total
energy processed to climb to unheard of levels, with unheard of
performance and efficiency.

The next key point to building and operating a small to medium
Tesla Magnifier is proper coil impedances in the secondary driver
and extra coil. The extra coil must have a higher impedance than
the secondary driver. The extra coil must be lower in resonate
frequency.

I have mentioned here that the 1/8th harmonic output of the
secondary driver coil matching the natural 1/4 wave resonate
frequency of the extra coil is the most efficient mode of
Magnifier operation. This is true, but don't get bogged down with
it. This system will work and fire (within reasonable limits)
with any extra coil that has a higher impedance and inductance
that the driver secondary. Let me give some tips.

I have found that most high performance 1/4 wave secondary coils
make lousy driver secondary coils in the Tesla Magnifier. The
reason is the impedance and inductance are too high, and the 1/4
wave coil is not designed or constructed to handle high current
outputs. 1/4 wave coils built per my instructions (posted here
several times) are designed to produce excellent 1/4 wave voltage
peaks, not 1/8th wave current. Your best bet is to wind a special
coil for use as a driver. With this in mind what type of coil
design would work best? Well my first decent driver coil was
built for use as a 1/4 wave resonator, but it dropped into the
role of a Magnifier driver without complaint; it had a nice low
aspect ratio, and it was wound with heavy stranded wire...

A good general purpose Magnifier secondary has a very low aspect
ratio for good tight coupling over the entire winding length (say
about 1.5:1). It is wound with heavy stranded insulated wire (say
#18 or larger) to help carry heavy RF currents with lower losses.
The frequency of the coil should not be too low, say in the area
of 400 kHz for most medium systems.

For the extra coil you want to pack a lot of inductance into a
small unit volume, but not too much. You will end up with an
amazingly short resonating coil if this is done properly. Use a
6" or 8" coil form with an aspect ratio a little over 2:1. For
winding the coil use say #20 -#24 double Formvar magnet wire. The
extra coil must be heavily top loaded with toroid discharger in
order to produce really killer performance, as is the case when
pumping a lot of energy through any magnet wire coil. The
impedance in the bare extra coil must be higher than the driver
coil by some margin, and the frequency of the extra coil should
be brought down around 200 kHz by top loading the coil with
discharger. The impedance of the driver must be low (heavy
stranded wire spaced by insulation) while the impedance of the
extra coil must be high (thin magnet wire, close wound turns)

The tank circuit of the Magnifier must be tuned to the same
frequency as the extra coil with discharger. Set the driver
secondary inside the primary and run a transmission line some 6-
8' to the extra coil. The extra coil must be away from any
field damping effects such as ground, large metal objects, other
coils etc. It must be allowed to resonate as freely as possible.

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
  Date: 12-23-93  06:38
  From: Brian Carling                              
    To: Joe Hayes                                                 
  Subj: Tubes
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
JH>Does anyone know a good source for buying 6KD6 tubes?
JH>The old horizontal output tubes.

Sources of Vacuum tubes ("valves") in the U.S.

Antique Audio                 (512) 467-0304
5555 N. Lamar, Bldg. H-105
Austin, TX 78751              Tubes, parts, books, kits

Antique Electronic Supply Co. (602) 820-5411
6221 S. Maple Avenue
Tempe, AZ 85283               (Tubes & other components)

Antique Radio Classified      (508) 371-0512   Write for free
sample.
P.O. Box 802                  Magazine. You'll find almost
ANYTHING here
Carlisle, MA 01741            for older radios, obscure parts,
tubes etc.

C & N Electronics             (800) 421-9397 / (612) 429-9397
6104 Egg Lake Road            FAX # (612) 429-0292
Hugo, MN 55038                Buy & sell tubes

CeCo Communications           (212) 646-6300
2115 Avenue X
Brooklyn, NY 11235            (Vacuum tubes)

Daily Electronics             (206) 896-8856 / (800) 346-6667
10914 N.E. 39th Street        Fax # (206) 896-5476
Vancouver, WA 98682           Tubes, all types.
                              (CW paddles, keyers etc.)

DH Distributors               (316) 684-0050
P.O. Box 48623
Wichita, KS 67201             Tubes, radio, TV, industrial

Electron Tube Enterprises     (802) 879-0611
Box 311
Essex, VT 05451               Tubes

Fair Radio Sales              (419) 227-6573
1016 E. Eureka                (419) 223-2196  FAX: (419) 227-1313
Box 1105                      Parts, transformers, power
supplies,
Lima, OH 45802                Surplus and gov't surplus radios

Fala Electronics              (No number listed) send s.a.s.e.
P.O. Box 1376-1
Milwaukee, WI 53201           Vacuum tubes

Kirby                         No number listed
298 W. Carmel Drive
Carmel, IN 46032              Tubes, new up to 90% off

New Sensor Corp.              (212) 529-0466  FAX: (212) 529-0486
133 Fifth Avenue              (800) 633-5477
New York, NY 10003            Vacuum tubes galore!

P.E.M. Tubes                  (916) 383-9107
7392 French Road
Sacramento, CA 95828          Tubes, radio, TV, transmitting, CRT

Lawrence Rauchwerger          (217) 352-6195
1610 1/2, W. Union St
Champaign, IL 61821           Tubes. S.A.S.E. list

RF Parts                      (619) 744-0700 (0728)
1320 Grand Avenue             (800) RF-PARTS or (800) 854-1927 to
order.
San Marcos, CA 92069          (RF power transistors & tubes)

Steinmetz Electronics         (219) 931-9316
7519 Maplewood Avenue
Hammond, IN 46324             Tubes

Tucker Surplus Sales          (214) 340-0631
1717 Reserve St.
Garland TX  75042
+1-800-527-4642 extension 135
Surplus radio & test equipment

Turner Electronics            No number listed
16701 Main Street Suite 121
Hesperia, CA 92345            Tubes, capacitors, S.A.S.E. list

Unity Electronics
P.O. Box 213
Elizabeth, NJ 07206           Vacuum tubes

Vacuum Tube Industries Inc.   (800) 528-5014 Ext. 74
P.O. Box 2009                 (508) 584-4500  FAX: (508) 584-0096
Brockton, MA 02405            Rebuilt power amplifier tubes etc.