
August 8th 07, 09:37 AM
posted to uk.rec.audio
|
|
300b/GM70 Amp
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
--
Tony Sayer
|

August 8th 07, 09:44 AM
posted to uk.rec.audio
|
|
300b/GM70 Amp
On Wed, 8 Aug 2007 10:37:35 +0100, tony sayer
wrote:
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
No, definitely the line output valve. After a few minutes the problem
was self-curing though - a slight popping noise, and there was a neat
melted hole at the top of the glass envelope.
d
--
Pearce Consulting
http://www.pearce.uk.com
|

August 8th 07, 11:18 AM
posted to uk.rec.audio
|
|
300b/GM70 Amp
"Don Pearce Posturing Pommy Turd "
tony sayer
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
No, definitely the line output valve.
** Another absolute BLOODY LIE !!
Only tubes supplied with 16 kV or more are at all involved in x-ray
generation.
.......... Phil
|

August 8th 07, 11:38 AM
posted to uk.rec.audio
|
|
300b/GM70 Amp
Phil Allison wrote:
"Don Pearce Posturing Pommy Turd "
tony sayer
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
No, definitely the line output valve.
** Another absolute BLOODY LIE !!
Only tubes supplied with 16 kV or more are at all involved in x-ray
generation.
......... Phil
I couldn't remember just what the voltage was, but I was sure its more
than 1kv.
--
Nick
|

August 8th 07, 11:50 AM
posted to uk.rec.audio
|
|
300b/GM70 Amp
On Wed, 08 Aug 2007 12:38:47 +0100, Nick Gorham
wrote:
Phil Allison wrote:
"Don Pearce Posturing Pommy Turd "
tony sayer
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
No, definitely the line output valve.
** Another absolute BLOODY LIE !!
Only tubes supplied with 16 kV or more are at all involved in x-ray
generation.
......... Phil
I couldn't remember just what the voltage was, but I was sure its more
than 1kv.
Well, this chap is aware of the phenomenon too
http://www.penders.cwc.net/otltbeht.html
Here too
http://www.r-type.org/exhib/aah0027.htm
d
--
Pearce Consulting
http://www.pearce.uk.com
|

August 8th 07, 12:12 PM
posted to uk.rec.audio
|
|
Don Pearce = Stinking LIAR
"Don Pearce = ****ing LIAR "
No, definitely the line output valve.
** Another absolute BLOODY LIE !!
Only tubes supplied with 16 kV or more are at all involved in x-ray
generation.
Well, this chap is aware of the phenomenon too
http://www.penders.cwc.net/otltbeht.html
Here too
http://www.r-type.org/exhib/aah0027.htm
** Neither backs up the idiotic LIE posted by Don Pearce
The second link is for a regulator tube rated at 25kV !!!
Don Pearce = Lying Pommy Turd.
........ Phil
|

August 8th 07, 12:29 PM
posted to uk.rec.audio
|
|
300b/GM70 Amp
Don Pearce wrote:
On Wed, 08 Aug 2007 12:38:47 +0100, Nick Gorham
wrote:
Phil Allison wrote:
"Don Pearce Posturing Pommy Turd "
tony sayer
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
No, definitely the line output valve.
** Another absolute BLOODY LIE !!
Only tubes supplied with 16 kV or more are at all involved in x-ray
generation.
......... Phil
I couldn't remember just what the voltage was, but I was sure its more
than 1kv.
Well, this chap is aware of the phenomenon too
http://www.penders.cwc.net/otltbeht.html
"The PD500 is also shielded. Not only does this valve dissipate 30 Watts
but it also emits X-Rays"
That will be the valve with its anode connected to the 25kv EHT line I
guess.
Here too
http://www.r-type.org/exhib/aah0027.htm
And that will be the valve with a max Va of 25kv
d
I am not suggesting that the valves mentioned can't produce x-rays, but
I am certain that a gm70 won't with 1kv on its anode.
--
Nick
|

August 8th 07, 12:41 PM
posted to uk.rec.audio
|
|
300b/GM70 Amp
On Wed, 08 Aug 2007 13:29:00 +0100, Nick Gorham
wrote:
Don Pearce wrote:
On Wed, 08 Aug 2007 12:38:47 +0100, Nick Gorham
wrote:
Phil Allison wrote:
"Don Pearce Posturing Pommy Turd "
tony sayer
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
No, definitely the line output valve.
** Another absolute BLOODY LIE !!
Only tubes supplied with 16 kV or more are at all involved in x-ray
generation.
......... Phil
I couldn't remember just what the voltage was, but I was sure its more
than 1kv.
Well, this chap is aware of the phenomenon too
http://www.penders.cwc.net/otltbeht.html
"The PD500 is also shielded. Not only does this valve dissipate 30 Watts
but it also emits X-Rays"
That will be the valve with its anode connected to the 25kv EHT line I
guess.
Here too
http://www.r-type.org/exhib/aah0027.htm
And that will be the valve with a max Va of 25kv
d
I am not suggesting that the valves mentioned can't produce x-rays, but
I am certain that a gm70 won't with 1kv on its anode.
Having just read that second link of mine, I find that Mullard called
the valve in question a line output valve, although it was used mainly
as an EHT stabilizer. 40 years have clearly fuddled my memory
slightly. I must ask nurse to tuck in my tartan blanket a bit tighter!
d
--
Pearce Consulting
http://www.pearce.uk.com
|

August 8th 07, 02:47 PM
posted to uk.rec.audio
|
|
300b/GM70 Amp
In article , Nick Gorham
writes
Don Pearce wrote:
On Wed, 08 Aug 2007 12:38:47 +0100, Nick Gorham
wrote:
Phil Allison wrote:
"Don Pearce Posturing Pommy Turd "
tony sayer
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
No, definitely the line output valve.
** Another absolute BLOODY LIE !!
Only tubes supplied with 16 kV or more are at all involved in x-ray
generation.
......... Phil
I couldn't remember just what the voltage was, but I was sure its more
than 1kv.
Well, this chap is aware of the phenomenon too
http://www.penders.cwc.net/otltbeht.html
"The PD500 is also shielded. Not only does this valve dissipate 30 Watts
but it also emits X-Rays"
That will be the valve with its anode connected to the 25kv EHT line I
guess.
The CRT also emitted X rays but these were very low mainly reduced by
the glass and metal shield which also contained the degauss coil...
Here too
http://www.r-type.org/exhib/aah0027.htm
And that will be the valve with a max Va of 25kv
d
I am not suggesting that the valves mentioned can't produce x-rays, but
I am certain that a gm70 won't with 1kv on its anode.
--
Tony Sayer
|

August 8th 07, 02:46 PM
posted to uk.rec.audio
|
|
300b/GM70 Amp
In article , Don Pearce
writes
On Wed, 8 Aug 2007 10:37:35 +0100, tony sayer
wrote:
In my earliest work days I designed colour TVs. We had an X-Ray
detector permanently covering the bench, because if the line output
valve got a few too many volts, and a bit too much current, its anode
would start to glow red, and X-Rays would come flooding out.
Wasn't that the shunt stabiliser that did that?.
Hence the metal can in some sets?..
No, definitely the line output valve. After a few minutes the problem
was self-curing though - a slight popping noise, and there was a neat
melted hole at the top of the glass envelope.
d
Beg to differ Don.. it was the PD 500 that was used for shunt
stabilisation in some Phillips chassis, notably the G6 and K7....
--
Tony Sayer
|
Thread Tools |
|
Display Modes |
Hybrid Mode
|
|