Jump to content

Sign in to follow this  
Tim Halse

Rola 77 MkIII

Recommended Posts

Posted (edited)

Love this thing.  Mono 1/4 inch track, all valve Aussie goodness.  Still runs beautifully after all these years.  See and hear it in action here: 

 

 

 

IMG_0235.jpg

IMG_0236.jpg

IMG_0237.jpg

Edited by Tim Halse
pic added

Share this post


Link to post
Share on other sites

Those machines can be pretty long lived. Don't know if you noticed, but the designer of these machines started a thread on them a few posts down this page. I used to come across them in my work as a Telstra Technical Officer working in Broadcasting. Going back into ancient history Telecom not only maintained the ABC's transmitter sites but also supplied technical staff at the ABC Radio studios. I have a service manual for these recorders and noticed the circuit schematic is dated 1962.

 

Like a lot of Australian made equipment from this era these have Ducon brand oil filled capacitors. While they are very reliable the oil contains PCB's (Polychlorinated Biphenyls). These are hazardous compounds that do not degrade in the environment so you need to avoid coming in contact with them such as could occur if the capacitors are leaking. At work we had a repository for PCB's where they were stored for eventual high temperature incineration. I believe this has been replaced by a process where the PCB's are exposed to an atmosphere of boiling nitric acid resulting in a harmless compound being produced. Any Ducon oil filled cap with N or S in the part number contains PCB's. We used to put a sticky label with a skull and crossbones on PCB containing equipment!

 

Keith 

Share this post


Link to post
Share on other sites

Very interesting Keith.  The caps certainly have been reliable.  The machine has been sitting dormant for a long time, but worked perfectly when I used it prior to this post.  

Share this post


Link to post
Share on other sites

Australia designed and produced some outstanding audio equipment in those days. 

It's tragic that few people know about them and that so much of our early audio history has been lost. 

 

Share this post


Link to post
Share on other sites


Yes Audiofeline.  Seems to me that Aussies are waking up very slowly to the superb quality of the gear we made a few decades ago.  I'll confess I don't mind them being oblivious to our homegrown gems.   I'll gladly pick up what they leave behind.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • Classifieds Statistics


    Currently Active Ads

    Total Sales (Since 2018)

    Total Sales Value (Last 14 Days)

    Total Ads Value (Since March 2020)
  • Recently Browsing   0 members

    No registered users viewing this page.


×
×
  • Create New...