Anyone recognise this ancient CRO? - Page 2

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
Re: Anyone recognise this ancient CRO?
On 7/07/2013 01:14 Phil Allison wrote:
Quoted text here. Click to load it

It looks like the CRT cathode + one side of the 6.3V heater supply (CRT  
pin 2) connects back to the bottom end of the Intensity pot. I was  
starting to wonder how it could work...



Re: Anyone recognise this ancient CRO?

"Bob Parker"
Quoted text here. Click to load it


** Despite being a 1.5MB jpeg, that scan has low resolution so the existence  
of dots is ambiguous.

BTW:

I once paid $25 for a service manual ( a B&W booklet ) with multiple  
schematics that lacked  ANY  dots  -  when the manual was prepared somehow  
they all failed to print.

The manual was for the EV " 2.0kW"  power amplifier featuring dual SMPSs and  
an unusually high component count.

It was real fun trying to work out where the dots should be and put them  
in....


....   Phil








Re: Anyone recognise this ancient CRO?
On 7/07/2013 12:03 Phil Allison wrote:
Quoted text here. Click to load it

The mid-1970s Yamaha service manual circuit diagrams had random dots and  
errors galore in them. Whoever drew them didn't have the slightest  
knowledge of electronics. I'd often waste more time trying to work out  
what was really connected to what, than finding the cause of the fault.



Re: Anyone recognise this ancient CRO?
On 05-Jul-13 1:11 PM, Bob Parker wrote:
Quoted text here. Click to load it

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

Cheers Don...


--  
Don McKenzie

$30 for an Olinuxino Linux PC:
We've slightly trimmed the long signature. Click to see the full one.
Re: Anyone recognise this ancient CRO?
On 7/07/2013 11:56 Don McKenzie wrote:

Quoted text here. Click to load it


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

I've gotta say that Jim Rowe is one incredibly knowledgeable bloke and  
he's still going >50 years later.


Bob


Re: Anyone recognise this ancient CRO?

"Bob Parker"
Quoted text here. Click to load it


** 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  



Re: Anyone recognise this ancient CRO?
On 7/07/2013 17:43 Phil Allison wrote:

Quoted text here. Click to load it

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


Bob



Re: Anyone recognise this ancient CRO?

"Bob Parker"
 Phil Allison wrote:
Quoted text here. Click to load 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



Re: Anyone recognise this ancient CRO?
On 7/07/2013 18:43 Phil Allison wrote:
Quoted text here. Click to load it


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


Re: Anyone recognise this ancient CRO?

"Bob Parker"
Quoted text here. Click to load it

** 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  



Re: Anyone recognise this ancient CRO?
On 8/07/2013 14:06 Phil Allison wrote:

Quoted text here. Click to load it

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



Re: Anyone recognise this ancient CRO?

"Bob Parker"
Quoted text here. Click to load it


** 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 ?


Quoted text here. Click to load it

** 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





Re: Anyone recognise this ancient CRO?
On 8/07/2013 16:54 Phil Allison wrote:
Quoted text here. Click to load it

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



Re: Anyone recognise this ancient CRO?

"Bob Parker"
 Phil Allison wrote:

Quoted text here. Click to load it

** Went there several times a week from 1973 till the finish of business in  
the late 80s. I even worked behind the counter for one day in 1973 and  
topped the sales list  -  Julie did the adding up at the end of each day and  
came over to tell me personally. There and then, Norm offered me a permanent  
job and was quite forceful about it. Since I was working for his son Bill at  
the time (Edge Electrix)  I foolishly declined.

Quoted text here. Click to load it

** I recall the conversation, Norm had added my invoice ( plus 27.5% sales  
tax ) and it came to $19.44.

Me: " 1944, ah that was a good year " .

Norm: " Don't say that -  1944 was a terrible year  !!

       I was in the Army driving bloody tanks back then   ".



Quoted text here. Click to load it

** Sorry, chucked all my yellow invoices decades ago.



...    Phil  



Re: Anyone recognise this ancient CRO?
On 08-Jul-13 10:03 AM, Bob Parker wrote:

Quoted text here. Click to load it

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:
We've slightly trimmed the long signature. Click to see the full one.
Re: Anyone recognise this ancient CRO?
On 8/07/2013 14:17 Don McKenzie wrote:
Quoted text here. Click to load it

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


Re: Anyone recognise this ancient CRO?

Quoted text here. Click to load it

I assume you mean RDS on Broadway near Harris St.
The pub on the corner (Agincourt) had a nice curry restaurant called
The Sri Lanka Room, I often had lunch there after going to RDS.






Re: Anyone recognise this ancient CRO?

"Bob Parker

Quoted text here. Click to load 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






Re: Anyone recognise this ancient CRO?

Quoted text here. Click to load it

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

Re: Anyone recognise this ancient CRO?

"Bob Parker"
Quoted text here. Click to load it


** 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





Site Timeline