Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Not Answered
  • Locked Locked
  • Replies 17 replies
  • Subscribers 32 subscribers
  • Views 1839 views
  • Users 0 members are here
Options
You may also be interested in
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Restoration of braided flexible cable, circa 1925 (Low Voltage!)

AncientMariner
Managed to locate a pair of circa 1925 Ericsson BBC Headphones suitable for my similar age Ericsson Crystal Radio. The braided flexible cable looks a bit mucky.

I suspect that the inners are tinsel wrapped cotton similar to that used by Post Office Telephones in the days of plaited handset flexibles of the 1940s 50s. I guess there would be rubber overall insulation beneath the braid.


Question is, how to clean the cable up?  Ideas that have so far come to mind are 1) Hand hot water with some washing up liquid, or 2) electrical solvent such as Isopropyl Alcohol. I am a little wary as to be would be kinder to the rubber over insulation (If any) and the tinsel covered cotton?


Either way, or any other way, would be to afterwards jang the wet flex close to a CH radiator to dry out.


Thanks.

Clive

  • 0
    Bluetooth conversion?


    ?
  • 0
    David, re Rugby Radio, back in October 2016 I posted about the Rugby Radio 16 kHz Morse transmissions being inadvertantly picked up at the Manor Studio when Tubular Bells was being recorded. https://www.theiet.org/Forums/Forum/messageview.cfm?catid=205&threadid=83767&STARTPAGE=1&FTVAR_FORUMVIEWTMP=Linear  

    I just checked and the YouTube video is still there: https://www.youtube.com/watch?v=b1g_wJQKihc


    The centre picture at http://ancient-mariner.co.uk/ was taken at Rugby Radio a few days after the MSF 60 kHz time signal had been transferred to Anthorn. The tower on the left, I took in July 2011 on Alexanderson Day, is one of those at Grimeton/SAQ  supporting their multiple-tuned aerial on 17.2 kHz.
    https://en.wikipedia.org/wiki/File:Grimetonmasterna.jpg

    Clive
  • 0

    davezawadi:

    I am afraid that none of them look at all like the original.




    Strangely, the Twisted Electric Cable covered by Rayon solid colour fabric TM13 Brown "looks" like the lead, which is twisted 2-core, but obviously a totally different  construction and not as flexible. Additionally I would need a "Y" shape.


    Currently the removal of the Bakelite caps off the metalwork is proving a little difficult...  I am currently resisting all temptation to  use a pair of water pump pliers!!!  The liberal application of WD-40 has not made any difference, but has loosened the muck on the diaphragms which can be accessed via the 10mm centre hole.

    Clive

  • 0
    Would popping them in the freezer do any harm or loosen them up, rather than applying heat?


    Andy Betteridge
  • 0
    In a former life I used to restore 1920s thru 1950s GPO phones, and my advice with tinsel flex is if you do use a wet solvent (water as opposed to IPA)... make absolutely sure it's rinsed clean of any detergent before drying. The fine tinsel can be attacked by some detergents.


    I had great success with very dilute biological washing powder for a couple of hours, with a gentle scrubbing with a toothbrush. As always, test a small section first!


    The method of terminating by wrapping with fuse wire is authentic for sure. I still have a 3Lb reel of no.35 SWG tinned copper wire that I used to use. :)


    Bind the wrapped ends with coloured beeswax impregnated cotton for best authenticity!
  • 0

    davidwalker2:

    Glad that it was all successful, Clive.  My daughter had the same treatment a year or so ago - completely satisfactory.

    Isn't the "click" inside your head weird?

    David




    You have started something there!



    I emailed the Consultant Ophthalmologist who carried out the SLT procedure and he replied, "Not really been asked this before, don’t think I hear a click as such, but will make a point of listening next time I do one so I can update you." I will be seeing him again 17th April. I also asked my cousin who is also my Optometrist and she replied, "Patients do tell me that they hear the clicks but I never knew that it was in the head!"

    The Consultant sits as close to the equipment as the patient, so an internal audible click would likely have been heard by both patient and Consultant.

    Interesting...

    Clive


  • 0
    Well you are heating and exploding a small volume of cells to make a hole. I'd be quite surprised if that was not accompanied by a mechanical shock wave, just one scaled to the size of the bomb crater will be more of  'tick' than a bang.

      I guess this shock-wave propagates through the mounts for the eyeball, to the ear sensors without going round though the air outside The whole point is that all the energy is absorbed and turned to heat  in a very small volume, so unlike the radio detection, it will not be from effects deeper within or crystal set detection onto nerves of teeth.

    Still very glad it worked.


    (in a former life I was briefly laser safety man at a well known university and we managed to make air click at the focus of a lens in time with the rep-rate of a high power laser, an in the dark you could see the focal spot glow, even though the laser was IR.  We also blew up a lens as well, but that was a mistake..)

Community Rules & Guidelines