MLU FORUM  

Go Back   MLU FORUM > GENERAL WW2 TOPICS > The Wireless Forum

Notices

Reply
 
Thread Tools Display Modes
  #1  
Old 08-09-20, 03:29
James D Teel II James D Teel II is offline
Registered User
 
Join Date: Jun 2019
Location: Edmond, Oklahoma, USA
Posts: 133
Default WS-19 Crystal Calibrator Dog Bone Question

It’s my understanding that there wasn’t a crystal calibrator for the MkII WS-19, only the MkIII. Since we can all agree the MkII uses a 6pt dog bone from the PSU to the main set and MkIII uses a 12pt dog bone, then what is this, and can it be repaired to work properly? By the way, I’ve seen this one, or an eerily similar to this one, on eBay before.
Attached Thumbnails
F4F779F1-0DB0-4E86-9471-BE7482C1BAAC.jpeg   AB011C15-71EC-4161-AAF9-CA8CB581950C.jpeg  
__________________
V/R

James D. Teel II
Edmond, Oklahoma
Retired Police Sergeant/Bomb Tech
1943 Willys MB/ITM jeep
1942 SS Cars No1Mk1 LtWt trailer
Reply With Quote
  #2  
Old 08-09-20, 03:50
David Dunlop David Dunlop is offline
Registered User
 
Join Date: Feb 2006
Location: Winnipeg, MB
Posts: 3,384
Default

Hi James.

This is a regular item on eBay and was covered some time ago here on MLU.

It is what is left of a Crystal Calibrator Power Cord Assembly for use on a Mk II 19-Set. Somebody has cut off the brown ID Collar that was around the wire loom, opposite the exit side for the calibrator feed line, and the line itself. My guess would be somebody wanted a simple 6-pin Mk II dog bone and did not realize what a rare piece of kit they were hacking up.

All Crystal Calibrator kits were issued with the calibrator, a 6-Pin dog bone connector, a 12-Pin dog bone connector, and a slow motion drive and manual.

The slow motion drive was to be used on a Mk II 19-Set to replace the standard drive on the Tuning Dial. All unused parts were to be returned to Stores.

I checked with the seller of this one last year and it came into his possession in this condition.

David
Reply With Quote
  #3  
Old 08-09-20, 19:20
James D Teel II James D Teel II is offline
Registered User
 
Join Date: Jun 2019
Location: Edmond, Oklahoma, USA
Posts: 133
Default

Thanks, David. How would one go about repairing it?
__________________
V/R

James D. Teel II
Edmond, Oklahoma
Retired Police Sergeant/Bomb Tech
1943 Willys MB/ITM jeep
1942 SS Cars No1Mk1 LtWt trailer
Reply With Quote
  #4  
Old 09-09-20, 01:41
Chris Suslowicz Chris Suslowicz is offline
Junior Password Gnome
 
Join Date: May 2007
Location: England
Posts: 814
Default

You would need a suitable length of 3-core braid-screened cable (like the kind that has been cut off) and the correct 3-pin Jones connector to match the plug on the calibrator front panel.

Then it's just a (simple?) matter of making up the new flying lead and fitting it to the existing cable - making sure you get the 12V and 250V connections correct.

Best regards,
Chris.
Reply With Quote
  #5  
Old 09-09-20, 01:57
Chris Suslowicz Chris Suslowicz is offline
Junior Password Gnome
 
Join Date: May 2007
Location: England
Posts: 814
Default

Quote:
Originally Posted by David Dunlop View Post
All Crystal Calibrator kits were issued with the calibrator, a 6-Pin dog bone connector, a 12-Pin dog bone connector, and a slow motion drive and manual.
There's even a 12pt-6pt variant with the calibrator lead, for use with sets modified to run from the later (Canadian No.2, British twin dynamotor, Eicor dynamotor, or the AC Supply Unit Rectifier No.1) supply units.

Other variant power supply to set cables include the RF Amplifier No.2 control cable (with HT2 brought out to a 2-pin socket so that the amplifier control relay can be inserted in series) - which again exists in 6-6, 12-6 and 12-12 variants, and a _very_ confusing to the unwary 12-12 lookalike that has the 2-pin socket connected to the +12-volt set (valve heaters and relay) supply and ground - this was for running the Power Supply and L.F. Amplifier units (1, 2 or 3) for the WS38, 88 or 31 AFV variants in AFVs - usually in conjunction with the Canadian Supply Unit No.2 to provide 12V from a 2-wire 24 volt supply in later tanks. (If you try using that particular cable on the RF amplifier it switches the amplifier to 'Send' and it stays there - the 12V won't damage the control relay but seriously confuses the owner!)

Best regards,
Chris.
Reply With Quote
  #6  
Old 09-09-20, 09:36
Chris Suslowicz Chris Suslowicz is offline
Junior Password Gnome
 
Join Date: May 2007
Location: England
Posts: 814
Default

Quote:
Originally Posted by Chris Suslowicz View Post
You would need a suitable length of 3-core braid-screened cable (like the kind that has been cut off) and the correct 3-pin Jones connector to match the plug on the calibrator front panel.
A further thought: it's possible that you could use modern flat 'earth braid' and slide suitable 3-core cable inside it. The result is likely to look a bit 'too new', though.

On a different note, I suspect the calibrators were only issued to Net control stations (i.e. with actual signals personnel) during WW2, and the lower level users simply netted to 'Control'. Using the calibrator is not that simple, and it's just one more thing to go wrong, so may have been 'dedicated wireless trucks only' issue.

Best regards,
Chris.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
19-Set Crystal Calibrator David Dunlop The Wireless Forum 17 08-09-19 20:58
For Sale: 12 pin dog bone kevin powles For Sale Or Wanted 1 30-01-19 23:31
RCA Crystal Calibrated Wavemeter things_green The Wireless Forum 2 14-07-17 08:17
For Sale: No19 Set Crystal Calibrator B. Harris For Sale Or Wanted 0 06-08-13 00:37
Wanted: Dog bone 12 pin to 6 pin chamberlain9g For Sale Or Wanted 0 17-06-12 14:46


All times are GMT +2. The time now is 19:03.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright © Maple Leaf Up, 2003-2016