Anyone recognise this ancient CRO?

[Phil Allison]

"Bob Parker"

Bob,
Sean Clarke from the back shed forum, provided this link:
http://members.melbpc.org.au/~sean/Famparc/RTnH_1963_-_Fully_Calibrated_Oscilloscope.pdf

A pdf of the CRO project Jim Rowe did in 1963 in R, TV & H

Thanks, Don. I hadn't looked at that site for a while. The CRO looks like
the 1963 unit Phil built.

** Not the same one - I built the simpler May '66 version, with 2MHz
bandwidth.

More compact, case less than half the size (5 x 7.5 x 8.5 inch) and used
only 5 valves:

1x12AT7 Schmitt trigger, 2x6BL8 for horizontal sweep and 2x6GH8 for the
vertical amp.

The shift, focus and astig pots were moved to the rear.

The 1S/cm time was left out as was DC coupling, illuminated graticule,
filter choke and brightness pot.

But the Mu-Metal CRT shield was kept and it uses a custom Ferguson tranny
( with copper strap) for all voltages.

The overall DC voltage on the CRT was increased to 650V, making the trace
quite bright and sharp.

I still have it and it still works with the original CRT.

It even got a recent up-grade with a BNC socket on the front !


..... Phil

 

[Bob Parker]

On 7/07/2013 17:43 Phil Allison wrote:

** Not the same one - I built the simpler May '66 version, with 2MHz
bandwidth.

More compact, case less than half the size (5 x 7.5 x 8.5 inch) and used
only 5 valves:

1x12AT7 Schmitt trigger, 2x6BL8 for horizontal sweep and 2x6GH8 for the
vertical amp.

The shift, focus and astig pots were moved to the rear.

The 1S/cm time was left out as was DC coupling, illuminated graticule,
filter choke and brightness pot.

But the Mu-Metal CRT shield was kept and it uses a custom Ferguson tranny
( with copper strap) for all voltages.

The overall DC voltage on the CRT was increased to 650V, making the trace
quite bright and sharp.

I still have it and it still works with the original CRT.

It even got a recent up-grade with a BNC socket on the front !


.... Phil

Still quite a respectable instrument. The BNC socket makes it a
hell of a lot easier to connect a real probe to it.


Bob

 

[Phil Allison]

"Bob Parker"
Phil Allison wrote:

** Not the same one - I built the simpler May '66 version, with 2MHz
bandwidth.

More compact, case less than half the size (5 x 7.5 x 8.5 inch) and used
only 5 valves:

1x12AT7 Schmitt trigger, 2x6BL8 for horizontal sweep and 2x6GH8 for the
vertical amp.

The shift, focus and astig pots were moved to the rear.

The 1S/cm time was left out as was DC coupling, illuminated graticule,
filter choke and brightness pot.

But the Mu-Metal CRT shield was kept and it uses a custom Ferguson tranny
( with copper strap) for all voltages.

The overall DC voltage on the CRT was increased to 650V, making the trace
quite bright and sharp.

I still have it and it still works with the original CRT.

It even got a recent up-grade with a BNC socket on the front !


Still quite a respectable instrument. The BNC socket makes it a hell of
a lot easier to connect a real probe to it.

** Others have mentioned seeing green CRTs used to make home brew TVs in the
B&W days.

Well, soon as I got my new CRO working, I hooked up the vertical, horizontal
and Z inputs to the vertical, horizontal and video circuits of a HMV 17
inch, console TV set.

Got a tiny green pic and my choice of negative or positive images - cool.

Current generation geeks have no idea ....



..... Phil

 

[keithr]

On 7/07/2013 5:43 PM, Phil Allison wrote:

"Bob Parker"
Bob,
Sean Clarke from the back shed forum, provided this link:
http://members.melbpc.org.au/~sean/Famparc/RTnH_1963_-_Fully_Calibrated_Oscilloscope.pdf

A pdf of the CRO project Jim Rowe did in 1963 in R, TV & H

Thanks, Don. I hadn't looked at that site for a while. The CRO looks like
the 1963 unit Phil built.


** Not the same one - I built the simpler May '66 version, with 2MHz
bandwidth.

More compact, case less than half the size (5 x 7.5 x 8.5 inch) and used
only 5 valves:

1x12AT7 Schmitt trigger, 2x6BL8 for horizontal sweep and 2x6GH8 for the
vertical amp.

The shift, focus and astig pots were moved to the rear.

The 1S/cm time was left out as was DC coupling, illuminated graticule,
filter choke and brightness pot.

But the Mu-Metal CRT shield was kept and it uses a custom Ferguson tranny
( with copper strap) for all voltages.

One of the little games in our apprentice workshop was when somebody had
got as far as finishing the power supply and had installed the tube, was
to distract them while a small magnet was slipped inside the umetal
screen leaving the victim trying to work out why he couldn't get a dot
on the screen.

The overall DC voltage on the CRT was increased to 650V, making the trace
quite bright and sharp.

I still have it and it still works with the original CRT.

It even got a recent up-grade with a BNC socket on the front !


.... Phil

 

[keithr]

On 7/07/2013 11:52 AM, Don McKenzie wrote:

On 06-Jul-13 8:03 PM, keithr wrote:
On 6/07/2013 6:41 AM, Don McKenzie wrote:
On 5/07/2013 5:51 PM, Phil Allison wrote:

We would have definitely got a failing mark though if it looked like
that.

It starting to look like a chassis that had holes drilled-punched for
yet another project, and with the above chassis components, I would
doubt that it was a kit of any description.

Possibly home brew from just a schematic.
I remember buying my first transistor in 1959? so I figure a valve CRO
could be anywhere from about 1935 to 1965.

CRO tube could have been war surplus, maybe even an ex radar part.

When I was a kid and TVs were rare luxury items, the guy from up the
road who was a radar tech built his own. He used a
CRT from a radar display, interesting picture, bright green and the
persistence turned any moving object into a smear
across the screen.

I saw part of the 56 Olympic games in a techs shop window in Williams
road Windsor (Vic) on a 5" green ex radar tube.

Don...

This would have been the late 40s. TVs were fearfully expensive, people

would just buy an antenna to try and make the neighbours believe that
they had one.

 

[Phil Allison]

"Bob Parker

Still quite a respectable instrument. The BNC socket makes it a hell of a
lot easier to connect a real probe to it.

** Anyone for a bit of electronics nostalgia ?

All the bits for my EA, May 66 CRO were purchased at Sydney's Radio Despatch
Service.

The power tranny was made by Ferguson at Chatswood.

The filter electros and polystyrenes were made by Ducon at Villawood.

The 9 pin sockets were made by McMurdo Australasia in Melbourne.

The wafer and slide switches were made by MSP in Ashfield.

All the valves were made by AWV in Rydalmere.

5W and 2W resistors and a switch pot were made by IRH at Kingsgrove.

However, the 3 inch CRT was made by Philips in Holland and the 12 pin socket
for same was made by McMurdo in the UK. The Sato knobs came from Japan.

The steel case was made by my brother in law, a welder by trade.



..... Phil

 

[John G]

keithr brought next idea :

On 7/07/2013 11:52 AM, Don McKenzie wrote:
On 06-Jul-13 8:03 PM, keithr wrote:
On 6/07/2013 6:41 AM, Don McKenzie wrote:
On 5/07/2013 5:51 PM, Phil Allison wrote:

We would have definitely got a failing mark though if it looked like
that.

It starting to look like a chassis that had holes drilled-punched for
yet another project, and with the above chassis components, I would
doubt that it was a kit of any description.

Possibly home brew from just a schematic.
I remember buying my first transistor in 1959? so I figure a valve CRO
could be anywhere from about 1935 to 1965.

CRO tube could have been war surplus, maybe even an ex radar part.

When I was a kid and TVs were rare luxury items, the guy from up the
road who was a radar tech built his own. He used a
CRT from a radar display, interesting picture, bright green and the
persistence turned any moving object into a smear
across the screen.

I saw part of the 56 Olympic games in a techs shop window in Williams
road Windsor (Vic) on a 5" green ex radar tube.

Don...

This would have been the late 40s. TVs were fearfully expensive, people would
just buy an antenna to try and make the neighbours believe that they had one.

There may have been amature TV but Public TV did not start until 1956
in Australia.
I Helped install a Training transmitter at Melbourne Tech (RMIT) in
1952 or 3. :-Z

--
John G

 

[Don McKenzie]

On 08-Jul-13 9:11 AM, John G wrote:

There may have been amature TV but Public TV did not start until 1956 in Australia.
I Helped install a Training transmitter at Melbourne Tech (RMIT) in 1952 or 3. :-Z

I remember seeing a demo at the exhibition buildings, which would have been 52 or 53.

may have even been part of the same package.

Cheers Don...


--
Don McKenzie

$30 for an Olinuxino Linux PC:
http://www.dontronics-shop.com/olinuxino.html

The World's Cheapest Computer:
DuinoMite the PIC32 $25 Basic Computer-MicroController
http://www.dontronics-shop.com/the-maximite-computer.html
Add VGA Monitor/TV, and PS2 Keyboard, or use USB Terminal
Arduino Shield, Programmed in Basic, or C.

 

[Bob Parker]

On 7/07/2013 18:43 Phil Allison wrote:

"Bob Parker"
Phil Allison wrote:


** Not the same one - I built the simpler May '66 version, with 2MHz
bandwidth.

More compact, case less than half the size (5 x 7.5 x 8.5 inch) and used
only 5 valves:

1x12AT7 Schmitt trigger, 2x6BL8 for horizontal sweep and 2x6GH8 for the
vertical amp.

The shift, focus and astig pots were moved to the rear.

The 1S/cm time was left out as was DC coupling, illuminated graticule,
filter choke and brightness pot.

But the Mu-Metal CRT shield was kept and it uses a custom Ferguson tranny
( with copper strap) for all voltages.

The overall DC voltage on the CRT was increased to 650V, making the trace
quite bright and sharp.

I still have it and it still works with the original CRT.

It even got a recent up-grade with a BNC socket on the front !


Still quite a respectable instrument. The BNC socket makes it a hell of
a lot easier to connect a real probe to it.


** Others have mentioned seeing green CRTs used to make home brew TVs in the
B&W days.

Well, soon as I got my new CRO working, I hooked up the vertical, horizontal
and Z inputs to the vertical, horizontal and video circuits of a HMV 17
inch, console TV set.

Got a tiny green pic and my choice of negative or positive images - cool.

Current generation geeks have no idea ....



.... Phil

I tried doing the same thing in the early 1970s with a brand-name
oscilloscope back in the PMG.

My own TV back then was an Astor 17", model ESJ if I remember correctly.
I remember buying a new vertical output transformer for it from Radio
Despatch Service.... Geoff Wood served me.


Bob

 

[Bob Parker]

** Anyone for a bit of electronics nostalgia ?

All the bits for my EA, May 66 CRO were purchased at Sydney's Radio Despatch
Service.

The power tranny was made by Ferguson at Chatswood.

The filter electros and polystyrenes were made by Ducon at Villawood.

The 9 pin sockets were made by McMurdo Australasia in Melbourne.

The wafer and slide switches were made by MSP in Ashfield.

All the valves were made by AWV in Rydalmere.

5W and 2W resistors and a switch pot were made by IRH at Kingsgrove.

However, the 3 inch CRT was made by Philips in Holland and the 12 pin socket
for same was made by McMurdo in the UK. The Sato knobs came from Japan.

The steel case was made by my brother in law, a welder by trade.



.... Phil

Wow! That was back when Australia had a manufacturing industry, before
governments put a stop to that.

Sounds like you were at RDS about as regularly as I was, before Bill
Edge, Geoff Wood and probably others went and did their own thing. I
remember meeting Fred (with the glasses) working behind the counter of
an East Hills service station one night after the demise of RDS. He
looked miserable.


Bob

 

[Bob Parker]

I've just received a pile of new photos of the CRO. You can see them at
http://tinyurl.com/2inchcro

Strange that it's got a mixture of old and mostly newer components in
it. The bloke's son says he saw it working in the 1960s... maybe that's
when it was built, also using a few waxed paper caps he had in stock?

The CRT is an RCA 902, making it look more like the CRO could be a clone
of the RCA 151-2 which also uses a 902 tube.


Bob

 

[Phil Allison]

"John G"

keithr brought next idea :

This would have been the late 40s. TVs were fearfully expensive, people
would just buy an antenna to try and make the neighbours believe that
they had one.

There may have been amature TV but Public TV did not start until 1956 in
Australia.

** Keith's story relates to the UK in the late 40s.

It has no relevance to the post he put it under.

Wot an ass.


.... Phil

 

[Phil Allison]

"Bob Parker"

Phil Allison
** Others have mentioned seeing green CRTs used to make home brew TVs in
the
B&W days.

Well, soon as I got my new CRO working, I hooked up the vertical,
horizontal
and Z inputs to the vertical, horizontal and video circuits of a HMV 17
inch, console TV set.

Got a tiny green pic and my choice of negative or positive images -
cool.

Current generation geeks have no idea ....


I tried doing the same thing in the early 1970s with a brand-name
oscilloscope back in the PMG.

My own TV back then was an Astor 17", model ESJ if I remember correctly. I
remember buying a new vertical output transformer for it from Radio
Despatch Service.... Geoff Wood served me.

** Yep, Geoff Wood and Norm Edge were the main guys.

Also Arthur the pom and gorgeous Julie - the office girl who sometimes
served lucky customers.


.... Phil

 

[Don McKenzie]

On 08-Jul-13 10:03 AM, Bob Parker wrote:

My own TV back then was an Astor 17", model ESJ if I remember correctly. I remember buying a new vertical output
transformer for it from Radio Despatch Service.... Geoff Wood served me.

and I'll almost bet the Astor 17" cost 199 guineas. that's the number I remember.

Cheers Don...


--
Don McKenzie

$30 for an Olinuxino Linux PC:
http://www.dontronics-shop.com/olinuxino.html

The World's Cheapest Computer:
DuinoMite the PIC32 $25 Basic Computer-MicroController
http://www.dontronics-shop.com/the-maximite-computer.html
Add VGA Monitor/TV, and PS2 Keyboard, or use USB Terminal
Arduino Shield, Programmed in Basic, or C.

 

[keithr]

On 8/07/2013 9:11 AM, John G wrote:

keithr brought next idea :
On 7/07/2013 11:52 AM, Don McKenzie wrote:
On 06-Jul-13 8:03 PM, keithr wrote:
On 6/07/2013 6:41 AM, Don McKenzie wrote:
On 5/07/2013 5:51 PM, Phil Allison wrote:

We would have definitely got a failing mark though if it looked like
that.

It starting to look like a chassis that had holes drilled-punched for
yet another project, and with the above chassis components, I would
doubt that it was a kit of any description.

Possibly home brew from just a schematic.
I remember buying my first transistor in 1959? so I figure a valve CRO
could be anywhere from about 1935 to 1965.

CRO tube could have been war surplus, maybe even an ex radar part.

When I was a kid and TVs were rare luxury items, the guy from up the
road who was a radar tech built his own. He used a
CRT from a radar display, interesting picture, bright green and the
persistence turned any moving object into a smear
across the screen.

I saw part of the 56 Olympic games in a techs shop window in Williams
road Windsor (Vic) on a 5" green ex radar tube.

Don...

This would have been the late 40s. TVs were fearfully expensive,
people would just buy an antenna to try and make the neighbours
believe that they had one.

There may have been amature TV but Public TV did not start until 1956 in
Australia.
I Helped install a Training transmitter at Melbourne Tech (RMIT) in 1952
or 3. :-Z

As phil has so helpfully pointed out, I wasn't living in Australia at

the time.

 

[Bob Parker]

On 8/07/2013 14:17 Don McKenzie wrote:

On 08-Jul-13 10:03 AM, Bob Parker wrote:

My own TV back then was an Astor 17", model ESJ if I remember
correctly. I remember buying a new vertical output
transformer for it from Radio Despatch Service.... Geoff Wood served me.

and I'll almost bet the Astor 17" cost 199 guineas. that's the number I
remember.

Cheers Don...

It probably did, which was a fortune back then. Luckily mine was
second-hand though a bit knocked around.

 

[Bob Parker]

On 8/07/2013 14:06 Phil Allison wrote:

** Yep, Geoff Wood and Norm Edge were the main guys.

Also Arthur the pom and gorgeous Julie - the office girl who sometimes
served lucky customers.


... Phil

I can picture Arthur and the rest like it was last week. Also the yellow
"Dr To Radio Despatch Service" invoices and the cabinets full of valves.
I don't recall Julie - I must have been one of the unlucky ones.

Bob

 

[Phil Allison]

"Bob Parker"

** Anyone for a bit of electronics nostalgia ?

All the bits for my EA, May 66 CRO were purchased at Sydney's Radio
Despatch
Service.

The power tranny was made by Ferguson at Chatswood.

The filter electros and polystyrenes were made by Ducon at Villawood.

The 9 pin sockets were made by McMurdo Australasia in Melbourne.

The wafer and slide switches were made by MSP in Ashfield.

All the valves were made by AWV in Rydalmere.

5W and 2W resistors and a switch pot were made by IRH at Kingsgrove.

However, the 3 inch CRT was made by Philips in Holland and the 12 pin
socket
for same was made by McMurdo in the UK. The Sato knobs came from Japan.

The steel case was made by my brother in law, a welder by trade.



Wow! That was back when Australia had a manufacturing industry, before
governments put a stop to that.

** Australia had a decent semiconductor industry in the 1960s.

https://sites.google.com/site/transistorhistory/australian-semiconductor-manufacturers

Includes plants set up by STC, Anodeon, Ducon and Fairchild.

I still have some AY8171 and AY9171 silicon power devices in gold flashed
TO66 packs from 1973.




.... Phil

 

[Phil Allison]

"Bob Parker"

Phil Allison wrote:


** Yep, Geoff Wood and Norm Edge were the main guys.

Also Arthur the pom and gorgeous Julie - the office girl who sometimes
served lucky customers.


I can picture Arthur and the rest like it was last week.

** There was " Neville " who was a bit fruity .......

Was Fred the tall, fair haired, solidly built guy ??

And the young guitar player with curly hair - what was his name ?

I don't recall Julie - I must have been one of the unlucky ones.

** Short, dark haired and very curvy .....


BTW:

Did you know that Norm Edge drove a tank in WW2 ?

Told me about it over the counter one day.


..... Phil

 

[Bob Parker]

On 8/07/2013 16:54 Phil Allison wrote:

"Bob Parker"
Phil Allison wrote:


** Yep, Geoff Wood and Norm Edge were the main guys.

Also Arthur the pom and gorgeous Julie - the office girl who sometimes
served lucky customers.


I can picture Arthur and the rest like it was last week.


** There was " Neville " who was a bit fruity .......

Was Fred the tall, fair haired, solidly built guy ??

And the young guitar player with curly hair - what was his name ?


I don't recall Julie - I must have been one of the unlucky ones.

** Short, dark haired and very curvy .....


BTW:

Did you know that Norm Edge drove a tank in WW2 ?

Told me about it over the counter one day.


.... Phil

My memory's kinda patchy for most of those blokes. As I recall, Fred was
fairly short with wavy black but greying hair and black-rimmed glasses.

Sounds like you got to know the people behind the counter better than I
did. I remember Norm Edge well but I never knew he was a tank driver(!).

The weird thing is that I think I still remember both of RDS's phone
numbers: 211-0191 and 211-0816. Was that them?


Bob