RCA P60928 convergence

[John-Del]

On Wednesday, July 19, 2017 at 2:57:18 PM UTC-4, Ian Field wrote:

"John-Del" <ohger1s@gmail.com> wrote in message
news:2d56773a-a266-426f-984d-2fdededa3e4a@googlegroups.com...
On Tuesday, July 18, 2017 at 1:37:35 PM UTC-4, Ian Field wrote:
jurb6006@gmail.com> wrote in message
news:c90a37ab-d11a-4c41-84d3-6edb39f6a0f9@googlegroups.com...
On Monday, July 17, 2017 at 2:25:37 PM UTC-5, Ian Field wrote:
jamesgmail.com> wrote in message
news:1a527a6f-6b49-454e-8fa1-dd1f71088fc4googlegroups.com...
I need help

If its that bad - you probably need to sort out the purity first.

I didn't think RCA PIL tubes still had those.

What is a PIL tube ?

May have been a copyright dodge to avoid the Trinitron.



Perhaps, but I think most of Sony's engineering efforts were to avoid
everyone else's patents. Their 70s power supply designs are a Rube
Goldberg's nightmare wrapped in a chain saw wielding mass murderer's warm
embrace. They weren't notably efficient or particularly well regulating,
so my guess is that they were building a unique design with no patents
(and really, who would patent such an abortion?).

I remember when NYC was reducing power during the 70s in an "energy
saving" attempt. Well Sony power supplies committed harakiri at not much
less than 100VAC, and lots of Trinitrons were blowing up during the
brown-outs.

As far as in-line tubes, I remember seeing mid 60s GE Portacolor TVs use
in-lines although I believe they were of delta configuration.

Its one or the other - delta is a bundle of guns and inline is exactly what
it says.

Yep, misspoke. The porta-color used an inline gun but retained the round RCA style shadow mask. When viewed up close, the round phoshpors looked a lot like the earlier delta. Later in-lines (including the Trini) used the rectangular slots that were quite obvious even when the TV was off.

 

On Wednesday, July 19, 2017 at 4:53:41 PM UTC-5, John-Del wrote:

On Wednesday, July 19, 2017 at 2:57:18 PM UTC-4, Ian Field wrote:
"John-Del" <ohger1s@gmail.com> wrote in message
news:2d56773a-a266-426f-984d-2fdededa3e4a@googlegroups.com...
On Tuesday, July 18, 2017 at 1:37:35 PM UTC-4, Ian Field wrote:
jurbmail.com> wrote in message
news:c90a37ab-d11a-4c41-84d3-6edb39f6a0f9@googlegroups.com...
On Monday, July 17, 2017 at 2:25:37 PM UTC-5, Ian Field wrote:
jamesgmail.com> wrote in message
news:1a527a6f-6b49-454e-8fa1-dd1f71088fc4googlegroups.com...
I need help

If its that bad - you probably need to sort out the purity first.

I didn't think RCA PIL tubes still had those.

What is a PIL tube ?

May have been a copyright dodge to avoid the Trinitron.



Perhaps, but I think most of Sony's engineering efforts were to avoid
everyone else's patents. Their 70s power supply designs are a Rube
Goldberg's nightmare wrapped in a chain saw wielding mass murderer's warm
embrace. They weren't notably efficient or particularly well regulating,
so my guess is that they were building a unique design with no patents
(and really, who would patent such an abortion?).

I remember when NYC was reducing power during the 70s in an "energy
saving" attempt. Well Sony power supplies committed harakiri at not much
less than 100VAC, and lots of Trinitrons were blowing up during the
brown-outs.

As far as in-line tubes, I remember seeing mid 60s GE Portacolor TVs use
in-lines although I believe they were of delta configuration.

Its one or the other - delta is a bundle of guns and inline is exactly what
it says.

Yep, misspoke. The porta-color used an inline gun but retained the round RCA style shadow mask. When viewed up close, the round phoshpors looked a lot like the earlier delta. Later in-lines (including the Trini) used the rectangular slots that were quite obvious even when the TV was off.

It is totally possible to use inline guns with a triad type shadow mask. In fact it holds its shape better than the slit type mask. Plus, with such poor resolution (screen pitch) it looked better.

Those GEs with the AA and AB chassis' were not something I was in love with to say the least. Had to resolder all those feedthroughs. Plus they used a wafer tuner which is harder to clean properly.

I did make some money fixing them but you can't charge that much on those elcheapo sets.

Actually though, it was very rare that I had to replace any parts in them.

 

[Ian Field]

<jurb6006@gmail.com> wrote in message
news:7c8415df-7758-4f20-b069-41496e88de4f@googlegroups.com...

On Wednesday, July 19, 2017 at 4:53:41 PM UTC-5, John-Del wrote:
On Wednesday, July 19, 2017 at 2:57:18 PM UTC-4, Ian Field wrote:
"John-Del" <ohger1s@gmail.com> wrote in message
news:2d56773a-a266-426f-984d-2fdededa3e4a@googlegroups.com...
On Tuesday, July 18, 2017 at 1:37:35 PM UTC-4, Ian Field wrote:
jurbmail.com> wrote in message
news:c90a37ab-d11a-4c41-84d3-6edb39f6a0f9@googlegroups.com...
On Monday, July 17, 2017 at 2:25:37 PM UTC-5, Ian Field wrote:
jamesgmail.com> wrote in message
news:1a527a6f-6b49-454e-8fa1-dd1f71088fc4googlegroups.com...
I need help

If its that bad - you probably need to sort out the purity first.

I didn't think RCA PIL tubes still had those.

What is a PIL tube ?

May have been a copyright dodge to avoid the Trinitron.



Perhaps, but I think most of Sony's engineering efforts were to avoid
everyone else's patents. Their 70s power supply designs are a Rube
Goldberg's nightmare wrapped in a chain saw wielding mass murderer's
warm
embrace. They weren't notably efficient or particularly well
regulating,
so my guess is that they were building a unique design with no
patents
(and really, who would patent such an abortion?).

I remember when NYC was reducing power during the 70s in an "energy
saving" attempt. Well Sony power supplies committed harakiri at not
much
less than 100VAC, and lots of Trinitrons were blowing up during the
brown-outs.

As far as in-line tubes, I remember seeing mid 60s GE Portacolor TVs
use
in-lines although I believe they were of delta configuration.

Its one or the other - delta is a bundle of guns and inline is exactly
what
it says.

Yep, misspoke. The porta-color used an inline gun but retained the round
RCA style shadow mask. When viewed up close, the round phoshpors looked a
lot like the earlier delta. Later in-lines (including the Trini) used
the rectangular slots that were quite obvious even when the TV was off.

It is totally possible to use inline guns with a triad type shadow mask.
In fact it holds its shape better than the slit type mask. Plus, with such
poor resolution (screen pitch) it looked better.

Those GEs with the AA and AB chassis' were not something I was in love
with to say the least. Had to resolder all those feedthroughs. Plus they
used a wafer tuner which is harder to clean properly.

I did make some money fixing them but you can't charge that much on those
elcheapo sets.

Actually though, it was very rare that I had to replace any parts in them.

Never seen an RCA TV in the UK, and I think the GE ones were co produced
with Hitachi.

Thorn Consumer Electronics standardised on RCA PIL tubes for a while. There
was a lot of re badging about - so hard to keep track.

One of the setups with RCA tubes used a low voltage flyback system - it was
hard to get transistors that could handle the current.

 

"Never seen an RCA TV in the UK, and I think the GE ones were co produced
with Hitachi. "

Here, Hitachi and RCA had quite the relationship. They built bigscreens for each other. You could open up an RCA and find a Hitachi or open up a Hitachi and find an RCA. The last two it seems were Mitsubishi and Sony if you actually wanted their product, everyone else eventually would just buy whatever and have it rebadged.

"One of the setups with RCA tubes used a low voltage flyback system - it was
hard to get transistors that could handle the current. "

Did not run into that problem. I did have some small Emersons that were hard to get a damper diode for because it was such high current. But not an RCA. But you said RCA tubes, that is not the fault of the tubes. It is the fault of the engineers.

 

On Tuesday, 18 July 2017 21:42:52 UTC+1, John-Del wrote:

On Tuesday, July 18, 2017 at 1:37:35 PM UTC-4, Ian Field wrote:
jurb6006@gmail.com> wrote in message
news:c90a37ab-d11a-4c41-84d3-6edb39f6a0f9@googlegroups.com...
On Monday, July 17, 2017 at 2:25:37 PM UTC-5, Ian Field wrote:
jamesgmail.com> wrote in message
news:1a527a6f-6b49-454e-8fa1-dd1f71088fc4googlegroups.com...

What is a PIL tube ?

May have been a copyright dodge to avoid the Trinitron.

Perhaps, but I think most of Sony's engineering efforts were to avoid everyone else's patents. Their 70s power supply designs are a Rube Goldberg's nightmare wrapped in a chain saw wielding mass murderer's warm embrace. They weren't notably efficient or particularly well regulating, so my guess is that they were building a unique design with no patents (and really, who would patent such an abortion?).

I remember when NYC was reducing power during the 70s in an "energy saving" attempt. Well Sony power supplies committed harakiri at not much less than 100VAC, and lots of Trinitrons were blowing up during the brown-outs.

The Trinitron when it worked right produced some fabulous images, but I think the tube was very finicky and required far more stringent manufacturing tolerances than the typical tube, hence the cost. Give it a small nudge and the shadow mask would shift or one of the wires would snap. Early tubes had the coaxial second anode connector and those tubes would short internally.

Don't miss those days. (much)

I remember the PSU boards in 70s trinitron sets. Talk about unnecessarily complex. As an experiment I once replaced the PSU board with a lightbulb as a dropper. (I forget how I provided filament power.) It worked, though voltage instability caused picture height instability.

I liked those sets as they were well valued but CRT emission tended to go. No-one else had worked out how to get the emission back, I did.


NT

 

[Ian Field]

<jurb6006@gmail.com> wrote in message
news:ffa9306f-11b2-4f30-9947-6b3eb5501f49@googlegroups.com...

"Never seen an RCA TV in the UK, and I think the GE ones were co produced
with Hitachi. "

Here, Hitachi and RCA had quite the relationship. They built bigscreens
for each other. You could open up an RCA and find a Hitachi or open up a
Hitachi and find an RCA. The last two it seems were Mitsubishi and Sony if
you actually wanted their product, everyone else eventually would just buy
whatever and have it rebadged.

"One of the setups with RCA tubes used a low voltage flyback system - it
was
hard to get transistors that could handle the current. "

Did not run into that problem. I did have some small Emersons that were
hard to get a damper diode for because it was such high current. But not
an RCA. But you said RCA tubes, that is not the fault of the tubes. It is
the fault of the engineers.

I only ever encountered the low voltage flyback system with certain RCA
tubes - and it was largely dictated by the design of the bonded on scan
yoke.

 

[Ian Field]

<tabbypurr@gmail.com> wrote in message
news:098a8905-0b92-4ef4-af0d-908b30257a14@googlegroups.com...

On Tuesday, 18 July 2017 21:42:52 UTC+1, John-Del wrote:
On Tuesday, July 18, 2017 at 1:37:35 PM UTC-4, Ian Field wrote:
jurb6006@gmail.com> wrote in message
news:c90a37ab-d11a-4c41-84d3-6edb39f6a0f9@googlegroups.com...
On Monday, July 17, 2017 at 2:25:37 PM UTC-5, Ian Field wrote:
jamesgmail.com> wrote in message
news:1a527a6f-6b49-454e-8fa1-dd1f71088fc4googlegroups.com...

What is a PIL tube ?

May have been a copyright dodge to avoid the Trinitron.

Perhaps, but I think most of Sony's engineering efforts were to avoid
everyone else's patents. Their 70s power supply designs are a Rube
Goldberg's nightmare wrapped in a chain saw wielding mass murderer's warm
embrace. They weren't notably efficient or particularly well regulating,
so my guess is that they were building a unique design with no patents
(and really, who would patent such an abortion?).

I remember when NYC was reducing power during the 70s in an "energy
saving" attempt. Well Sony power supplies committed harakiri at not much
less than 100VAC, and lots of Trinitrons were blowing up during the
brown-outs.

The Trinitron when it worked right produced some fabulous images, but I
think the tube was very finicky and required far more stringent
manufacturing tolerances than the typical tube, hence the cost. Give it
a small nudge and the shadow mask would shift or one of the wires would
snap. Early tubes had the coaxial second anode connector and those tubes
would short internally.

Don't miss those days. (much)

I remember the PSU boards in 70s trinitron sets. Talk about unnecessarily
complex. As an experiment I once replaced the PSU board with a lightbulb
as a dropper. (I forget how I provided filament power.) It worked, though
voltage instability caused picture height instability.

I liked those sets as they were well valued but CRT emission tended to go.
No-one else had worked out how to get the emission back, I did.

With monitors - I discovered that some 'genius' at Philips had published a
bulletin stated that stable SMPSUs meant CRT heaters only needed 6.15V. Most
manufacturers fell for it, and most CRTs ended up with poisoned cathodes.

There was plenty of evidence that some engineers were just turning the wick
up in the PSU. My solution was to fit a Shottky-barrier heater rectifier,
that needed an added snubber to prevent the flyback peaks killing the
rectifier, and improvements to the filter circuit. Some already had Sb
rectifier, so there wasn't much I could do.