UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Telephony and Telecomms

Notices

Vintage Telephony and Telecomms Vintage Telephones, Telephony and Telecomms Equipment

Closed Thread
 
Thread Tools
Old 21st Mar 2018, 12:19 pm   #1
boombox
Pentode
 
Join Date: Mar 2012
Location: Rotherham, South Yorkshire, UK.
Posts: 152
Default 4T receiver

Just looking into getting a new 4T receiver, seen on Telephone Lines he does a modern replacement - but the connections are different. Will this mean replacing the spade terminals on the wires in the handset with a female connector?

Thanks!
boombox is offline  
Old 21st Mar 2018, 12:39 pm   #2
G6Tanuki
Dekatron
 
G6Tanuki's Avatar
 
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,953
Default Re: 4T receiver

The one in thta link looks to have 'mini blade' connectors so yes you'll need to replace the spades you already have.
G6Tanuki is offline  
Old 21st Mar 2018, 12:44 pm   #3
Nickthedentist
Dekatron
 
Nickthedentist's Avatar
 
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,820
Default Re: 4T receiver

I suspect those were out of a Statesman or similar.

If you're adept with an iron (and lucky!), you might be able to tack the right style of push-on connector onto the existing tags, then cover everything with heatshrink.

The tinsel wire in curly handset cords are nightmare to re-terminate so I'd try to preserve the spade terminals rather than chop them off.

Alternatively, have you tried requesting a normal 4T here? There are loads about, I'm sure.

Nick.
Nickthedentist is online now  
Old 21st Mar 2018, 7:39 pm   #4
Sparks
Heptode
 
Join Date: Oct 2006
Location: Leeds, West Yorkshire, UK.
Posts: 593
Default Re: 4T receiver

Unless I'm mistaken, these 'other' 4T inserts look to have an impedance of 600 ohms. I don't know if that is significant technically.
Sparks is offline  
Old 21st Mar 2018, 7:57 pm   #5
G6Tanuki
Dekatron
 
G6Tanuki's Avatar
 
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,953
Default Re: 4T receiver

"Mini blade" push-on connectors are available easily: your local Halfords will have them. In your situation I'd get a set of mini-blades, then cut the actual spade-part off your eisting tags, leaving the crimp-part of the old spades still attached to the cable [so preserving the existing contact with the 'tinsel']

This is essentially using the crimped part of the old spades as a 'bootlace ferrule' to fit into the mini-blade connectors where the cable would usually go. Then push the crimped-part of the old spade-tags-on-the-ends-of-the-wires into the mini-blade, and crimp. Job done!
G6Tanuki is offline  
Old 21st Mar 2018, 8:56 pm   #6
Nickthedentist
Dekatron
 
Nickthedentist's Avatar
 
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,820
Default Re: 4T receiver

I like that idea, G6T.
Nickthedentist is online now  
Old 21st Mar 2018, 10:22 pm   #7
russell_w_b
Dekatron
 
russell_w_b's Avatar
 
Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
Posts: 3,684
Default Re: 4T receiver

Quote:
Originally Posted by Sparks View Post
'...these 'other' 4T inserts look to have an impedance of 600 ohms. I don't know if that is significant technically.'
I tried a 'new' plastic 4T from a BT Ambassador against a 'traditional' 4T as used in a 700 series instrument.

* Old receiver: 61.6 Ohms Z @ 1kHz.
* New receiver: 462 Ohms Z @ 1kHz.

The sound of the newer receiver is faint compared to the original in a 746 instrument, where the impedances of the sidetone network are optimised for the original 4T impedance, but is still audible.
__________________
Regds,

Russell W. B.
G4YLI.
russell_w_b is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 11:30 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.