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Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 2:54 pm
by Paul Maybury
I've often thought about getting some t shirts done with the logo seen here;
http://www.oneillassociates.com.au/~pon ... alogue.pdf
Anyone have any ideas about how to that?
Cheers, Paul

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 3:07 pm
by The Tasmanian
Lets all pitch in for a one off TShirt for Rick for Christmas.
He can wear it under his flack jacket.

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 3:12 pm
by The Tasmanian
WOW!
Paul - that tape machine catalog pic has a 3 inch 24 track!!!!

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 3:40 pm
by Paul Maybury
http://dastshirtautomat.com/#home
These folk could do it, and their local to me.

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 3:42 pm
by Chris H
hell yes! I'm up for an Optro T shirt or three......... I'd even buy one for Rick ! ha ha!! :ar!

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 4:17 pm
by Paul Maybury
The first price break is at 5 units. Anyone else?

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 7:25 pm
by The Tasmanian
OK - I'm in,
even just to wear it near a mastering facility in Leichardt,
- or wherever the old Festival techs hang out!

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 8:41 pm
by Chris H
Here are the pics of the inductors. The board is under the other circuit board.
...... :( double post somehow?

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 8:51 pm
by Chris H
Here are the pics of the inductors. The board is under the other circuit board.

Inductors.jpg


....interesting that there is an opto cell on this board as well.

Comp_Inside.jpg

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 11:04 pm
by walding
Chris H wrote:
Paul Maybury wrote:I love my Optro gear, but I'd love it a lot more if there were some goddam schematics....


The story is they all went into the dumpster. Schematics and everything from his Clayton workshop.
A sad story really. Graham was a brilliant man whose business ventures did not bring him the economic security he deserved. With the recording equipment, accoustic design, micro processors and Sontron and Editron editing and syncro systems he covered a a lot of ground as an inovator.

Worth a read:

http://www.aesmelbourne.org.au/graham-thirkell/
click the links at the bottom for some great optro pics and info

http://www.retrotechnology.com/herbs_st ... itron.html

Press release for the comp:

ATN-Optro740-processor-3-sml.jpg


also I cant help thinking this comp, what with the EQ faders and the spectral comp section was the inspiration for the Avalon 747


Reverse smily face on the GE :x

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Thu Oct 22, 2015 11:12 pm
by Sammas
Paul Maybury wrote:The first price break is at 5 units. Anyone else?


*Waves hand*


The Tasmanian wrote:WOW!
Paul - that tape machine catalog pic has a 3 inch 24 track!!!!


MCI also prototyped a 3" 32 track tape machine. I don't think any 3" machines ever made production though.

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Fri Oct 23, 2015 11:41 am
by Paul Maybury
T shirts run at about $45 each!! Pricey.
Does anyone have any other suggestions for somewhere that will do a short for us?
Cheers, Paul

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Fri Oct 23, 2015 1:43 pm
by rick
What good can come of me optro bashing
None me thinks ? I better stop

But i can say your not quite right in the rollout call of technology cris t .


all the aussie tv stations including the abc had stacks and stacks of neve consoles
and studer tape machines
It was a total credit that optro got a look in at all little lone
With as many products as have surfaced .
If they had of hit the ball out of the park they would have made a F@#$ing fortune
And their multitrack tape machine was nothing if not an inspiration punt !

But reality is Lots of companies including neve went off the rails and bankrupt
making top quality Audio stuff , its a mugs game really

I am sure we all understand optro is home grown and graham was a genius .

I did the turtlerock tshirts at redbubble.com
Thats the simplest way to get it going
Its probably time i reran the forum tees too

But ill leave the secret society of broken optro technolgy to make their own :)

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Fri Oct 23, 2015 1:51 pm
by rick
Optro tshirt logo


Optro
" hey do you have a schematic ?"

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Fri Oct 23, 2015 2:16 pm
by walding
rick wrote:Optro tshirt logo


Optro
" hey do you have a schematic ?"



=))

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Fri Oct 23, 2015 3:25 pm
by Paul Maybury
Good one Rick. Maybe that can go on the back of the T shirt.
It is the secret handshake of the Optro Geek Club, after all.

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Fri Oct 23, 2015 9:27 pm
by EvLoutonian
Haha
I like it.
That would be enough to tip me over the edge & get one!
As long as it was available in small chap size.
(:

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Sat Oct 24, 2015 6:31 am
by Alastair Reynolds
Ah Optro and the "no docs patent" . In all my travels around little radio sites in Australia, I have only ever come across 1 Optro schematic which I will dig out and post for all to see.it is for a 50 w rms power amp. I have a 203 eq,,but no paperwork of any sort for it.

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Sat Oct 24, 2015 8:59 am
by Chris H
I have hand drawn schematics for the 7500....will dig them yo and scan them.

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Sat Oct 24, 2015 9:05 am
by EvLoutonian
Good one blokes!
Would be interesting to see what documentation is out there, even if just for the sake of piecing together some history of this company's output together..

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Sun Nov 01, 2015 5:04 pm
by Alastair Reynolds
*** STOP PRESS ***
Prepare to get harder than a cats head.
I was doing some prep work today for a big AM transmission repair job I'm doing next week and was with my colleague who has been in the Audio: radio/TV game for 50+ years at his factory unit. He's a bit of a collector/ bowerbird and while we were packing the truck I noticed next to a pair of M49s he has 2x Optro 740. I asked what the story with them was. They were ex TV station, ABC or TCN, he couldn't remember . I asked casually " I don't suppose you've got a manual or schematic for them, his reply was "should have, I used to" we went up to his library level and poked around.... No 740 manual ..... It must be in one of the other boxes I haven't put on the shelves yet.. Bugger. We'll have to look when we get back... However, on a different shelf next to the 1960 Gates catalogue... A complete manual for a Optro 306 dual band limiter with schematic., which is probably the same as the compressor stage of the 740. I will scan it and make it available to all and will advise on the forum when it is ready . The schematic is A2 size so I'll need to go to office works to scan. We will also continue looking for the full 740 manual when I get back from the TX job in a week

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Sun Nov 01, 2015 5:53 pm
by EvLoutonian
Alastair Reynolds wrote:... A complete manual for a Optro 306 dual band limiter with schematic., which is probably the same as the compressor stage of the 740. I will scan it and make it available to all and will advise on the forum when it is ready . The schematic is A2 size so I'll need to go to office works to scan. We will also continue looking for the full 740 manual when I get back from the TX job in a week


You bloomin beautayyyy!

Great work, Alastair!
Shall be interesting to see what else also surfaces from your mate's document library, too.

Cheers, and shall look forward to more updates.
(:

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Sun Nov 01, 2015 9:09 pm
by Junction
Alastair, I've got a 302 and 303 limiter-compressor, would be keen to see the schematic of the 306, could be a chance there is some similarities :)

Cheers mate

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Sun Nov 01, 2015 9:58 pm
by Alastair Reynolds
I'll put this here to prove it exists, apologies for the shadow.
resolution is crappy as I've shrunk it to 800 x 600, but I'll email it if you want it before I get back.

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Mon Nov 02, 2015 9:10 am
by Chris H
Fantastic!

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Mon Nov 02, 2015 11:13 am
by Junction
awesome Alastair :) Wenever you get around to it, would you be able to email it to me? A print of the picture is a bit fuzzy, not so easy to read the component values.

Cheers

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Mon Nov 02, 2015 6:51 pm
by rob
now i'm interested!
I've had a few optro pieces through the workshop over the years. And without any documents got them all going.
Including building a replacement module to replace one of those coloured potted modules ... without knowing the contents of the sealed module ... spooky

that schematic that Alistair has uncovered is extraordinarily interesting. Yes, it is optical gain reduction ... with a twist. Who can spot it? It is something that you'd be more likely to expect in processing audio for radio transmission so Alistair will see it. Who else?

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Tue Nov 03, 2015 10:59 am
by Junction
rob wrote:now i'm interested!
Yes, it is optical gain reduction ... with a twist. Who can spot it? It is something that you'd be more likely to expect in processing audio for radio transmission so Alistair will see it. Who else?


... is it as simple as a dual band limiter, most commonly found in radio broadcast chains in the 70's?

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Tue Nov 03, 2015 5:35 pm
by Alastair Reynolds
Correct, Dual band, I think the split is at about 300Hz, Plus the release time for the LF is longer than the HF .
I have had the advantage of reading the rest of the documentation (briefly before I left to travel north) It is a very interesting device. I hope this goes someway to helping with other Optro Compressors and I will keep on the case to find more Optro documentation and make it available.

Re: OPTRO 740 comp / EQ doc's / schemo's ? (WANTED)

PostPosted: Tue Nov 03, 2015 8:10 pm
by rob
Good work team