Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

America: Land of the Free, Because of the Brave

"Jim Thompson" wrote in
message ...
Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)

...Jim Thompson

Did it have paper caps?

I recall taking a 5" B/W Sony VHF only television into a repair shop
and was told they didn't work on transistor sets. I took it apart only
to find that a capacitor lead needed resoldering. That was probably
1968 or so, I was 12.

Jim Thompson wrote:

Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)


I built more mean stuff when I was a kid. An amplifier with several big
horizontal flyback tubes in there etc. 900V on the plates, directly
cascaded out of 230V grounded mains, sans transformer because that would
have cost too much...

Actually I still got that amp but a typical 120V circuit is too wimpy
for it.

--
Regards, Joerg

http://www.analogconsultants.com

On Tue, 20 Mar 2007 00:34:10 GMT, Joerg
wrote:

Jim Thompson wrote:

Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)


I built more mean stuff when I was a kid. An amplifier with several big
horizontal flyback tubes in there etc. 900V on the plates, directly
cascaded out of 230V grounded mains, sans transformer because that would
have cost too much...

Actually I still got that amp but a typical 120V circuit is too wimpy
for it.

I built at least six different tube power amplifiers, starting with
6V6, then 6L6, then a variety of 6550, KT88 and similar.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

America: Land of the Free, Because of the Brave

"Joerg" wrote in message
...
Jim Thompson wrote:

Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)


I built more mean stuff when I was a kid. An amplifier with several big
horizontal flyback tubes in there etc. 900V on the plates, directly
cascaded out of 230V grounded mains, sans transformer because that would
have cost too much...

Actually I still got that amp but a typical 120V circuit is too wimpy
for it.

How could you build such an amp and not connect it to your available
230 volt 30 amp mains? It has to use less power than an electric oven!

"Joerg" wrote in message
et...
Lord Garth wrote:

"Joerg" wrote in message
...

Jim Thompson wrote:


Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)


I built more mean stuff when I was a kid. An amplifier with several big
horizontal flyback tubes in there etc. 900V on the plates, directly
cascaded out of 230V grounded mains, sans transformer because that would
have cost too much...

Actually I still got that amp but a typical 120V circuit is too wimpy
for it.


How could you build such an amp and not connect it to your available
230 volt 30 amp mains? It has to use less power than an electric oven!


That's because this amp has what we used to call a "white knuckle
supply". Three cascade stages to get to about 930 volts without a
transformer. Here in the US this doesn't work because the 240V we have
for ovens, A/C or dryers is just the two phases. Each side is 120V to
ground so you'd need a large iso transformer.


So you have 230 volts phase to phase? 3 phase 120 volt yields 208 phase to
phase.
Was your home supplied with 3 phase power?

Jim Thompson wrote:

On Tue, 20 Mar 2007 00:34:10 GMT, Joerg
wrote:


Jim Thompson wrote:


Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)


I built more mean stuff when I was a kid. An amplifier with several big
horizontal flyback tubes in there etc. 900V on the plates, directly
cascaded out of 230V grounded mains, sans transformer because that would
have cost too much...

Actually I still got that amp but a typical 120V circuit is too wimpy
for it.


I built at least six different tube power amplifiers, starting with
6V6, then 6L6, then a variety of 6550, KT88 and similar.


Mine was with PL509 tubes. Those are color TV flyback drivers rated at
30W plate dissipation. But you could push them up to 70-80W dissipation
before the plates went from cherry-red to orange.

Of course having to always watch the plates and make sure they don't go
too far into an orange glow was a hassle. So, I built the gorilla of all
amplifiers with two of these puppies:
http://datasheets.electron-tube.net/...q/QB5-1750.pdf

5kV on the plates. Those tubes can easily pack away 500W of plate
dissipation without a whiff of redness. Each.

--
Regards, Joerg

http://www.analogconsultants.com

Lord Garth wrote:

"Joerg" wrote in message
et...

Lord Garth wrote:


"Joerg" wrote in message
. net...


Jim Thompson wrote:



Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)


I built more mean stuff when I was a kid. An amplifier with several big
horizontal flyback tubes in there etc. 900V on the plates, directly
cascaded out of 230V grounded mains, sans transformer because that would
have cost too much...

Actually I still got that amp but a typical 120V circuit is too wimpy
for it.


How could you build such an amp and not connect it to your available
230 volt 30 amp mains? It has to use less power than an electric oven!


That's because this amp has what we used to call a "white knuckle
supply". Three cascade stages to get to about 930 volts without a
transformer. Here in the US this doesn't work because the 240V we have
for ovens, A/C or dryers is just the two phases. Each side is 120V to
ground so you'd need a large iso transformer.



So you have 230 volts phase to phase? 3 phase 120 volt yields 208 phase to
phase.
Was your home supplied with 3 phase power?


No, in the US we have mostly two-phase into houses, 180 degrees.
Basically a center-tapped transformer. In Europe it was real three phase
(230V to ground and 380V between phases).

BTW your newsreader sometimes drops groups from the follow-up.

--
Regards, Joerg

http://www.analogconsultants.com

"Joerg" wrote in message
et...

BTW your newsreader sometimes drops groups from the follow-up.


I cutting them out Joerg...I also jump into the middle at times.

Re the voltage, to get 120 volts from a center tapped transformer,
on one phase, each of the three phases would need to be 240 volts.
It would seem to be available but at what cost?

"Jim Thompson" wrote in
message ...
Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)

...Jim Thompson


From the PAS2 manual:

"However, stereophony introduces problems in high fidelity reproduction
which can diminish your enjoyment of your hi fi system unless these problems
are understood and corrected."

Stereophony? That's a word I've not heard.

I built a later Dynaco preamp but it was solid state (PAS3?), also an SAE
power amp from parts that my buddy got me (he worked there), and I built the
#1 Ampzilla kit (the GAS company). Those were fun times indeed. I'm afraid
those days of reaping the satisfaction and knowledge from assembling your
own stuff is long gone. Too bad for the current generation of wannabes, eh?

Thanks for the link, Jim.

Bob

On Mon, 19 Mar 2007 19:22:11 -0700, "Bob"
wrote:


"Jim Thompson" wrote in
message ...
Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)

...Jim Thompson


From the PAS2 manual:

"However, stereophony introduces problems in high fidelity reproduction
which can diminish your enjoyment of your hi fi system unless these problems
are understood and corrected."

Stereophony? That's a word I've not heard.

I built a later Dynaco preamp but it was solid state (PAS3?), also an SAE
power amp from parts that my buddy got me (he worked there), and I built the
#1 Ampzilla kit (the GAS company). Those were fun times indeed. I'm afraid
those days of reaping the satisfaction and knowledge from assembling your
own stuff is long gone. Too bad for the current generation of wannabes, eh?

Thanks for the link, Jim.

Bob


Certainly brings back fond memories!

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

America: Land of the Free, Because of the Brave

Lord Garth wrote:

"Joerg" wrote in message
...

Jim Thompson wrote:


Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)


I built more mean stuff when I was a kid. An amplifier with several big
horizontal flyback tubes in there etc. 900V on the plates, directly
cascaded out of 230V grounded mains, sans transformer because that would
have cost too much...

Actually I still got that amp but a typical 120V circuit is too wimpy
for it.


How could you build such an amp and not connect it to your available
230 volt 30 amp mains? It has to use less power than an electric oven!


That's because this amp has what we used to call a "white knuckle
supply". Three cascade stages to get to about 930 volts without a
transformer. Here in the US this doesn't work because the 240V we have
for ovens, A/C or dryers is just the two phases. Each side is 120V to
ground so you'd need a large iso transformer.

--
Regards, Joerg

http://www.analogconsultants.com

and here we have a fine group i shall dub "the mu men" or "the mu-see-ums"
;-))

solid, easy to get along with and sensible, no foolishness with p-layer
punch thru or bonding failures!

and tubes may actually be repaired too, nothing like those flimsy silicon
flakes!

:-))



"Jim Thompson" wrote in
message ...
Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

America: Land of the Free, Because of the Brave

wrote in message
t...
and here we have a fine group i shall dub "the mu men" or "the
mu-see-ums"
;-))

solid, easy to get along with and sensible, no foolishness with p-layer
punch thru or bonding failures!

and tubes may actually be repaired too, nothing like those flimsy silicon
flakes!


Haven't seen any latch up in a long while but my friend plugged in his USB
thumb drive the other day and the magic smoke came out.

Upon prying it open, a SMD coil had decided to end its little life. It
might be
possible to repair the drive.

Not quite as easy to repair as those hot electron FETs though.

On Tue, 20 Mar 2007 08:50:03 -0800, Joerg
wrote:

[snip]

In the US it is not very common to have three-phase available at the end
user. Part of our community does have a three-phase distribution at the
kilovolt level. Then they hang each transformer between two of the
phases. Pretty much in a statistical or round-robin scheme to provide a
somewhat equal load. The transformer secondary is a center tapped
120V+120V and typically feeds 3-5 houses.

Industry sometimes uses three-phase but I remember a case where a
business wanted to get that and the CEO almost fell off his chair when
he received the quote from the utility. Then they opted to buy the
diesel generators they had rented as a temporary power source. This is
what you get with monopoly situations I guess.

In the mid '60's I had a house in old-town Scottsdale (69th Place and
Oak) with 3-phase power. Makes for very efficient A/C compressors.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

America: Land of the Free, Because of the Brave

Lord Garth wrote:

"Joerg" wrote in message
et...

BTW your newsreader sometimes drops groups from the follow-up.



I cutting them out Joerg...I also jump into the middle at times.

Re the voltage, to get 120 volts from a center tapped transformer,
on one phase, each of the three phases would need to be 240 volts.
It would seem to be available but at what cost?


In the US it is not very common to have three-phase available at the end
user. Part of our community does have a three-phase distribution at the
kilovolt level. Then they hang each transformer between two of the
phases. Pretty much in a statistical or round-robin scheme to provide a
somewhat equal load. The transformer secondary is a center tapped
120V+120V and typically feeds 3-5 houses.

Industry sometimes uses three-phase but I remember a case where a
business wanted to get that and the CEO almost fell off his chair when
he received the quote from the utility. Then they opted to buy the
diesel generators they had rented as a temporary power source. This is
what you get with monopoly situations I guess.

--
Regards, Joerg

http://www.analogconsultants.com

wrote:

and here we have a fine group i shall dub "the mu men" or "the mu-see-ums"
;-))

solid, easy to get along with and sensible, no foolishness with p-layer
punch thru or bonding failures!

and tubes may actually be repaired too, nothing like those flimsy silicon
flakes!

:-))


Tubes are for real men. When they fail, they often do so in a rather
spectacular manner. Molten glass splattering about and all that.

--
Regards, Joerg

http://www.analogconsultants.com

Joerg wrote:

Tubes are for real men. When they fail, they often do so in a rather
spectacular manner. Molten glass splattering about and all that.


Real men used tubes made with Beryllium Oxide Ceramic, instead of
wimpy glass. Forced air cooling ruled! Arrh! Arrh! Arrh!


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Jim Thompson wrote:

On Tue, 20 Mar 2007 08:50:03 -0800, Joerg
wrote:

[snip]

In the US it is not very common to have three-phase available at the end
user. Part of our community does have a three-phase distribution at the
kilovolt level. Then they hang each transformer between two of the
phases. Pretty much in a statistical or round-robin scheme to provide a
somewhat equal load. The transformer secondary is a center tapped
120V+120V and typically feeds 3-5 houses.

Industry sometimes uses three-phase but I remember a case where a
business wanted to get that and the CEO almost fell off his chair when
he received the quote from the utility. Then they opted to buy the
diesel generators they had rented as a temporary power source. This is
what you get with monopoly situations I guess.


In the mid '60's I had a house in old-town Scottsdale (69th Place and
Oak) with 3-phase power. Makes for very efficient A/C compressors.


In Germany all houses except maybe some really old ones have
three-phase. So I was a bit non-plussed when we moved here and, yeah,
there is 2x200A going into the house but I can't run my welder and can't
run some other stuff either :-(

BTW did you find a chess timer? If not I had posted a few links. The
last one would probably fit quite well. Around $40 IIRC, even has a belt
clip.

--
Regards, Joerg

http://www.analogconsultants.com

On Tue, 20 Mar 2007 14:58:47 -0400, Meat Plow
wrote:

On Mon, 19 Mar 2007 16:50:35 -0700, Jim Thompson wrote:

Subject: Oh my! Nostalgia!
From: Jim Thompson
Newsgroups: alt.binaries.schematics.electronic,sci.electronics .design
Date: Mon, 19 Mar 2007 16:50:35 -0700

Oh my! Nostalgia!

Stumbled onto this site...

http://tdsl.duncanamps.com/schematics2.php?make=Dynaco

I built the FM3 and the PAS2 when I was a kid ;-)

The first true hifi I heard was a Dynaco amp and speakers. Really rocked
my world way back then.

My first high-power amplifier was a version of Williamson-Ultralinear,
but wasn't built from a kit... straight from schematic to chassis.

Of course I had an advantage... I was raised in a radio-TV repair shop
and had access to chassis punches, etc., and an account with the local
electronics wholesale house.

I only learned in recent years that my dad had instructed the
wholesale house personnel that I was to have free rein to wander the
product storage aisles and get whatever I wanted... charged to his
account ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

America: Land of the Free, Because of the Brave

Jim Thompson wrote:

..My first high-power amplifier was a version of Williamson-Ultralinear,
but wasn't built from a kit... straight from schematic to chassis.

..Of course I had an advantage... I was raised in a radio-TV repair shop
and had access to chassis punches, etc., and an account with the local
electronics wholesale house.

I only learned in recent years that my dad had instructed the
wholesale house personnel that I was to have free rein to wander the
product storage aisles and get whatever I wanted... charged to his
account ;-)


A lot of good that did you, long after the fact.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On Tue, 20 Mar 2007 20:01:31 GMT, "Michael A. Terrell"
wrote:

Jim Thompson wrote:

.My first high-power amplifier was a version of Williamson-Ultralinear,
but wasn't built from a kit... straight from schematic to chassis.

.Of course I had an advantage... I was raised in a radio-TV repair shop
and had access to chassis punches, etc., and an account with the local
electronics wholesale house.

I only learned in recent years that my dad had instructed the
wholesale house personnel that I was to have free rein to wander the
product storage aisles and get whatever I wanted... charged to his
account ;-)


A lot of good that did you, long after the fact.

No. I was just careful, because I thought I had to pay for it.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

America: Land of the Free, Because of the Brave

"Jim Thompson" wrote in
message ...
No. I was just careful, because I thought I had to pay for it.

You were under the impression -- for years -- that some day you'd be getting
this huge bill in the mail for all the parts you'd ever used? :-)

Joel Kolstad wrote:

"Jim Thompson" wrote in
message ...

No. I was just careful, because I thought I had to pay for it.


You were under the impression -- for years -- that some day you'd be getting
this huge bill in the mail for all the parts you'd ever used? :-)


Be careful. Jim's pa is alive and kicking. He has a PC, could read this
and get an idea...

--
Regards, Joerg

http://www.analogconsultants.com

On Tue, 20 Mar 2007 15:09:13 -0700, "Joel Kolstad"
wrote:

"Jim Thompson" wrote in
message ...
No. I was just careful, because I thought I had to pay for it.

You were under the impression -- for years -- that some day you'd be getting
this huge bill in the mail for all the parts you'd ever used? :-)



Knowing my father, I never knew when the shoe would drop.

Maybe this year on his 89th Birthday ?:-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

America: Land of the Free, Because of the Brave

John Larkin wrote:

On Tue, 20 Mar 2007 13:10:48 -0700, Jim Thompson
wrote:


On Tue, 20 Mar 2007 20:01:31 GMT, "Michael A. Terrell"
wrote:


Jim Thompson wrote:


.My first high-power amplifier was a version of Williamson-Ultralinear,

but wasn't built from a kit... straight from schematic to chassis.

.Of course I had an advantage... I was raised in a radio-TV repair shop

and had access to chassis punches, etc., and an account with the local
electronics wholesale house.

I only learned in recent years that my dad had instructed the
wholesale house personnel that I was to have free rein to wander the
product storage aisles and get whatever I wanted... charged to his
account ;-)


A lot of good that did you, long after the fact.

No. I was just careful, because I thought I had to pay for it.

...Jim Thompson


My uncle Sheldon had a tv repair shop, so I had an infinite supply of
old chassis and parts. Plus he had been a radio operator in WWII and,
on leaving the service, had somehow stolen a shed full of exotic
military gear. And when I was a kid, there was mountains of WWII
surplus electronics around, like a wing-pod radar for $70, or pmt's
and crt's for $1.

I don't think I ever saw Sheldon without a long-neck Dixie beer in one
hand and a cigarette in the other, and a honkey-tonk woman nearby. He
used to put a few cases of empties out on the front porch and the
Dixie truck driver, seeing them, would replace them with full ones.


The cigarettes were probably hand rolled Bull-Durhams?

--
Regards, Joerg

http://www.analogconsultants.com

On Tue, 20 Mar 2007 13:10:48 -0700, Jim Thompson
wrote:

On Tue, 20 Mar 2007 20:01:31 GMT, "Michael A. Terrell"
wrote:

Jim Thompson wrote:

.My first high-power amplifier was a version of Williamson-Ultralinear,
but wasn't built from a kit... straight from schematic to chassis.

.Of course I had an advantage... I was raised in a radio-TV repair shop
and had access to chassis punches, etc., and an account with the local
electronics wholesale house.

I only learned in recent years that my dad had instructed the
wholesale house personnel that I was to have free rein to wander the
product storage aisles and get whatever I wanted... charged to his
account ;-)


A lot of good that did you, long after the fact.

No. I was just careful, because I thought I had to pay for it.

...Jim Thompson

My uncle Sheldon had a tv repair shop, so I had an infinite supply of
old chassis and parts. Plus he had been a radio operator in WWII and,
on leaving the service, had somehow stolen a shed full of exotic
military gear. And when I was a kid, there was mountains of WWII
surplus electronics around, like a wing-pod radar for $70, or pmt's
and crt's for $1.

I don't think I ever saw Sheldon without a long-neck Dixie beer in one
hand and a cigarette in the other, and a honkey-tonk woman nearby. He
used to put a few cases of empties out on the front porch and the
Dixie truck driver, seeing them, would replace them with full ones.

John

On Wed, 21 Mar 2007 00:04:42 GMT, Joerg
wrote:

John Larkin wrote:

On Tue, 20 Mar 2007 13:10:48 -0700, Jim Thompson
wrote:


On Tue, 20 Mar 2007 20:01:31 GMT, "Michael A. Terrell"
wrote:


Jim Thompson wrote:


.My first high-power amplifier was a version of Williamson-Ultralinear,

but wasn't built from a kit... straight from schematic to chassis.

.Of course I had an advantage... I was raised in a radio-TV repair shop

and had access to chassis punches, etc., and an account with the local
electronics wholesale house.

I only learned in recent years that my dad had instructed the
wholesale house personnel that I was to have free rein to wander the
product storage aisles and get whatever I wanted... charged to his
account ;-)


A lot of good that did you, long after the fact.

No. I was just careful, because I thought I had to pay for it.

...Jim Thompson


My uncle Sheldon had a tv repair shop, so I had an infinite supply of
old chassis and parts. Plus he had been a radio operator in WWII and,
on leaving the service, had somehow stolen a shed full of exotic
military gear. And when I was a kid, there was mountains of WWII
surplus electronics around, like a wing-pod radar for $70, or pmt's
and crt's for $1.

I don't think I ever saw Sheldon without a long-neck Dixie beer in one
hand and a cigarette in the other, and a honkey-tonk woman nearby. He
used to put a few cases of empties out on the front porch and the
Dixie truck driver, seeing them, would replace them with full ones.


The cigarettes were probably hand rolled Bull-Durhams?


No, they came out of some pack. They killed him, of course.

John

John Larkin wrote:

On Wed, 21 Mar 2007 00:04:42 GMT, Joerg
wrote:


John Larkin wrote:


On Tue, 20 Mar 2007 13:10:48 -0700, Jim Thompson
wrote:



On Tue, 20 Mar 2007 20:01:31 GMT, "Michael A. Terrell"
wrote:



Jim Thompson wrote:


.My first high-power amplifier was a version of Williamson-Ultralinear,


but wasn't built from a kit... straight from schematic to chassis.

.Of course I had an advantage... I was raised in a radio-TV repair shop


and had access to chassis punches, etc., and an account with the local
electronics wholesale house.

I only learned in recent years that my dad had instructed the
wholesale house personnel that I was to have free rein to wander the
product storage aisles and get whatever I wanted... charged to his
account ;-)


A lot of good that did you, long after the fact.

No. I was just careful, because I thought I had to pay for it.

...Jim Thompson


My uncle Sheldon had a tv repair shop, so I had an infinite supply of
old chassis and parts. Plus he had been a radio operator in WWII and,
on leaving the service, had somehow stolen a shed full of exotic
military gear. And when I was a kid, there was mountains of WWII
surplus electronics around, like a wing-pod radar for $70, or pmt's
and crt's for $1.

I don't think I ever saw Sheldon without a long-neck Dixie beer in one
hand and a cigarette in the other, and a honkey-tonk woman nearby. He
used to put a few cases of empties out on the front porch and the
Dixie truck driver, seeing them, would replace them with full ones.


The cigarettes were probably hand rolled Bull-Durhams?



No, they came out of some pack. They killed him, of course.


But it sounds like he still lived a heck of a life.

--
Regards, Joerg

http://www.analogconsultants.com

Jim Thompson wrote:

No. I was just careful, because I thought I had to pay for it.


I DID have to pay for it. It wasn't very long till I had a $3000 a
month line of credit, at several wholesalers, with several offering to
raise the figure anytime I wanted to. It was VERY tempting to really
stock up parts for the shop, and the service trucks.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"Joerg" wrote in message
et...



In the US it is not very common to have three-phase available at the end
user. Part of our community does have a three-phase distribution at the
kilovolt level. Then they hang each transformer between two of the
phases. Pretty much in a statistical or round-robin scheme to provide a
somewhat equal load. The transformer secondary is a center tapped
120V+120V and typically feeds 3-5 houses.

Industry sometimes uses three-phase but I remember a case where a
business wanted to get that and the CEO almost fell off his chair when
he received the quote from the utility. Then they opted to buy the
diesel generators they had rented as a temporary power source. This is
what you get with monopoly situations I guess.


I did the network and phone wiring at a metal fabrication shop last year.
The 17 automated welders required such an amount of power that the
utility had to replan the area due to draw these machines demanded.

The company did specialized fabrication for semiconductor fabs and
other clean rooms.

I think it's impressive when you can suck down the grid!

The scary part is to see the differences between the plan and the
'as built' considering some of the chemicals inside the pipes.

"Jim Thompson" wrote in
message ...

In the mid '60's I had a house in old-town Scottsdale (69th Place and
Oak) with 3-phase power. Makes for very efficient A/C compressors.


I'll bet it did! I'll see if the irrigation pumps at the Lago Vista golf
club are
3 phase...it might help their electric bill this summer.

"Michael A. Terrell" wrote in message
...
Joerg wrote:

Tubes are for real men. When they fail, they often do so in a rather
spectacular manner. Molten glass splattering about and all that.


Real men used tubes made with Beryllium Oxide Ceramic, instead of
wimpy glass. Forced air cooling ruled! Arrh! Arrh! Arrh!


Hmm, like in the microwave oven?

Nice stuff to breathe, eh!

Lord Garth wrote:

"Michael A. Terrell" wrote in message
...
Joerg wrote:

Tubes are for real men. When they fail, they often do so in a rather
spectacular manner. Molten glass splattering about and all that.


Real men used tubes made with Beryllium Oxide Ceramic, instead of
wimpy glass. Forced air cooling ruled! Arrh! Arrh! Arrh!


Hmm, like in the microwave oven?

Nice stuff to breathe, eh!


More like 4CX250 to $CX5000.

Real men know better than to breath in Beryllium Oxide.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On Mon, 19 Mar 2007 22:47:52 -0400, hapticz wrote:

and here we have a fine group i shall dub "the mu men" or "the mu-see-ums"
;-))

solid, easy to get along with and sensible, no foolishness with p-layer
punch thru or bonding failures!

and tubes may actually be repaired too, nothing like those flimsy silicon
flakes!

I've actually seen _tubes_ repaired. They were big metal-ceramic
transmitting tubes, like 3CX15000Z. A little company in Louisiana (there
must be a lot of them, scattered about) cuts a dead tube open on a lathe
and installs a fresh cathode assembly, which includes a copper tube to
connect to the vacuum pump. They also have glassblower's lathes for
handling the old tubes, but I don't think any of those are still in
service.

"Stephen J. Rush" wrote in message
news

I've actually seen _tubes_ repaired. They were big metal-ceramic
transmitting tubes, like 3CX15000Z. A little company in Louisiana (there
must be a lot of them, scattered about) cuts a dead tube open on a lathe
and installs a fresh cathode assembly, which includes a copper tube to
connect to the vacuum pump. They also have glassblower's lathes for
handling the old tubes, but I don't think any of those are still in
service.

The radio station I worked in my high school years had their transmitting
tubes rebuilt as well. The repair wasn't possible when lightening hit the
tower however, the tubes in the final had quarter sized holes melted
through the glass!

Lord Garth wrote:

"Stephen J. Rush" wrote in message
news

I've actually seen _tubes_ repaired. They were big metal-ceramic
transmitting tubes, like 3CX15000Z. A little company in Louisiana (there
must be a lot of them, scattered about) cuts a dead tube open on a lathe
and installs a fresh cathode assembly, which includes a copper tube to
connect to the vacuum pump. They also have glassblower's lathes for
handling the old tubes, but I don't think any of those are still in
service.

The radio station I worked in my high school years had their transmitting
tubes rebuilt as well. The repair wasn't possible when lightening hit the
tower however, the tubes in the final had quarter sized holes melted
through the glass!


The water cooled 25 KW finals used in the RCA TTU-25 series used
optically aligned elements, and no one ever managed to get more than 50%
output out of a rebuilt tube which is sad, because RCA designed it to be
rebuilt. The bottom of the tube had a removable cover to get inside the
tube, through the water jacket. Most attempts at rebuilding were so bad
that you couldn't even use the tube in the aural cabinet for 12 KW. The
tube used a pair of 1000 A, 1.5 VAC heaters.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"Michael A. Terrell" wrote in message
...

The water cooled 25 KW finals used in the RCA TTU-25 series used
optically aligned elements, and no one ever managed to get more than 50%
output out of a rebuilt tube which is sad, because RCA designed it to be
rebuilt. The bottom of the tube had a removable cover to get inside the
tube, through the water jacket. Most attempts at rebuilding were so bad
that you couldn't even use the tube in the aural cabinet for 12 KW. The
tube used a pair of 1000 A, 1.5 VAC heaters.


Was there a mechanical alignment issue? The tubes I spoke of were only
pumping 5KW but the four of them were glowing cherry red. The transmitter
was only off after the station cut over to the standby transmitter about
once
a month.

Lord Garth wrote:

"Michael A. Terrell" wrote in message
...

The water cooled 25 KW finals used in the RCA TTU-25 series used
optically aligned elements, and no one ever managed to get more than 50%
output out of a rebuilt tube which is sad, because RCA designed it to be
rebuilt. The bottom of the tube had a removable cover to get inside the
tube, through the water jacket. Most attempts at rebuilding were so bad
that you couldn't even use the tube in the aural cabinet for 12 KW. The
tube used a pair of 1000 A, 1.5 VAC heaters.


Was there a mechanical alignment issue? The tubes I spoke of were only
pumping 5KW but the four of them were glowing cherry red. The transmitter
was only off after the station cut over to the standby transmitter about
once
a month.


They never figured out what the problem was. RCA had shut down the
small line that made the tubes and scrapped all production equipment,
along with the original drawings, so no one knew exactly how they were
made, or how to rebuild them.

The tubes went from $400 for new production, to $30,000 for used or
surplus tubes that still had full output. When they were in production,
they were too cheap to replace, so no one tried to rebuild them. Once
in a while a transmitter building was cleaned out or torn down and they
would find a stash of spare finals that some engineer had put away for
future use when they were cheap. A good final was worth more than the
transmitter that used it by the early '90s, when I moved and rebuilt a
TTU-25B. The tubes were made for UHF service, and the odd filament made
them useless to ham radio service so they were kind of orphans.

BTW, these tubes are in one of the early RCA Transmitting Tube
manuals. I think it was in the TT-5 printing.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On 2007-03-20, Lord Garth wrote:

"Joerg" wrote in message
et...

That's because this amp has what we used to call a "white knuckle
supply". Three cascade stages to get to about 930 volts without a
transformer. Here in the US this doesn't work because the 240V we have
for ovens, A/C or dryers is just the two phases. Each side is 120V to
ground so you'd need a large iso transformer.

So you have 230 volts phase to phase? 3 phase 120 volt yields 208 phase to
phase.
Was your home supplied with 3 phase power?

Much of the world has 230 phase to neutral.



Bye.
Jasen