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 Audio (record players, hi-fi etc)

Notices

Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment.

Closed Thread
 
Thread Tools
Old 18th Jan 2020, 11:48 pm   #1
GWR1971
Triode
 
Join Date: May 2016
Location: Colchester, Essex, UK.
Posts: 22
Default Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Hi all,

I've dug my Dad's 50s-era Dansette Diploma (unused since the early-mid 60s) out of the loft, and I'm interested in coaxing it back to full health as my first proper restoration project.

Previously I've refurbed the belts and rubber parts in a 1960s open-reel tape deck, and that's the full extent of my restoration experience thus far. I have a multimeter, a very basic knowledge of electronics, and I can solder.

What would you recommend as my next step? Is there the equivalent of Dansette Repair for Dummies out there?

EDIT - apologies, I completely missed the "Reviving your record player" sticky thread. I'm reading it now!
Attached Thumbnails
Click image for larger version

Name:	diplomat.jpg
Views:	234
Size:	47.2 KB
ID:	197371  
GWR1971 is offline  
Old 19th Jan 2020, 9:37 am   #2
John10b
Nonode
 
Join Date: Nov 2016
Location: Aberaeron, Ceredigion, Wales, UK.
Posts: 2,869
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

I would suggest you down load the circuit diagram, up top right, it only costs £1.99 and is well worth having.
John
John10b is offline  
Old 19th Jan 2020, 9:48 am   #3
Viscount
Heptode
 
Join Date: Jan 2018
Location: Folkestone, Kent, UK.
Posts: 709
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Take photos of everything you do and have containers for all the parts, clean all parts as you proceed.
Viscount is offline  
Old 19th Jan 2020, 10:01 am   #4
John10b
Nonode
 
Join Date: Nov 2016
Location: Aberaeron, Ceredigion, Wales, UK.
Posts: 2,869
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Further to my post #2, it doesn’t look as if the circuit for your Dansette is on the list. However this model has been discussed on this forum before, so if you put in details in “search” you will find a link, this should prove informative.
John
John10b is offline  
Old 19th Jan 2020, 10:12 am   #5
Station X
Moderator
 
Station X's Avatar
 
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,192
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

It's been suggested in another thread that this is the circuit.

https://www.vintage-radio.net/forum/...4&d=1394320249
__________________
Graham. Forum Moderator

Reach for your meter before you reach for your soldering iron.
Station X is offline  
Old 19th Jan 2020, 12:35 pm   #6
DonaldStott
Octode
 
DonaldStott's Avatar
 
Join Date: Aug 2015
Location: Glasgow, UK.
Posts: 1,840
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

You really can't do much better than systematically working your way through the excellent Sticky by Darren-UK "Reviving your old record player"

https://www.vintage-radio.net/forum/...ad.php?t=75401

Augment this with various Google searches e.g. lots of useful YouTube videos on Dansettes, and if you come across any particular problems not already covered (unlikely!) then there is a wealth of knowledge and experience on this Forum.

All models of Dansette have a lot in common and require a variety of basic skills in electronics, mechanics and (sometimes) woodworking.

Cleaning all the different types of material (plastic, brass, Rexine etc.) is often a challenge and your Dansette Diploma looks as if it needs a lot of TLC!

My advice is to Post lots of pictures at various stages and keep detailed notes of which part goes where?
__________________
BVWS Member

Last edited by DonaldStott; 19th Jan 2020 at 12:47 pm.
DonaldStott is offline  
Old 19th Jan 2020, 1:33 pm   #7
Edward Huggins
Dekatron
 
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Your Dansette was made in 1954 using the BSR "Regent" deck. The arm on this is very heavy with little scope for tracking weight adjustment. I think I can see the on your tone arm that the original BSR TC4 mono cartridge has been removed and it's been replaced with a stereo-compatible type. To protect your LPs (of which most will be Stereo) you will need to add weight to the end of the tone arm to try to get it down to c.5 grams.
I can also confirm that the circuit in Post#5 is that same as used in your player. No belts are used, but the rubber idler wheel which drives the inner rim of the turntable may need refinishing on it's edge. The chassis is mains-isolated so safer to work on than many of this type.
__________________
Edward.
Edward Huggins is offline  
Old 20th Jan 2020, 1:15 pm   #8
GWR1971
Triode
 
Join Date: May 2016
Location: Colchester, Essex, UK.
Posts: 22
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Many thanks, all!

Just FWIW, I'm not planning to use it to play modern records, so I'm not too bothered about the tracking weight at this point.

Is refinishing the idler wheel something I can do at home, or does that require a specialist?
GWR1971 is offline  
Old 20th Jan 2020, 3:29 pm   #9
OldTechFan96
Octode
 
OldTechFan96's Avatar
 
Join Date: Jul 2017
Location: Newcastle Upon Tyne, Tyne & Wear, UK.
Posts: 1,177
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

I'd start with some cold (not plugged into the mains!) resistance checks with your DMM once the amp is on your bench:

Check that the on/off switch is working.

Check the continuity of the primary and secondary of the mains transformer.

Check the continuity of the primary and secondary of the audio output transformer.

Check the health of the rectifier using the diode check function of your DMM.

Measure the resistance across the terminals of the speaker to make sure it is not open.

The idler wheel can be resurfaced using an electric drill and some fine sandpaper.
OldTechFan96 is offline  
Old 26th Jan 2020, 4:31 pm   #10
GWR1971
Triode
 
Join Date: May 2016
Location: Colchester, Essex, UK.
Posts: 22
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Thanks all. Could someone please clarify the meaning of this, from the sticky thread?

"At this stage it's a wise idea to do a quick check on the electrical condition of the smoothing/reservoir capacitor (see post #10). Take the capacitor out of circuit (ie disconnect electrically) and switch your meter to its highest Ohms range. Connect the meter across the tags and watch the reading"

Does the bold section actually mean "desolder and remove the capacitor"?
GWR1971 is offline  
Old 26th Jan 2020, 4:36 pm   #11
dazzlevision
Dekatron
 
Join Date: Sep 2003
Location: Near Swindon, North Wiltshire, UK.
Posts: 3,595
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Quote:
Originally Posted by GWR1971 View Post
Thanks all. Could someone please clarify the meaning of this, from the sticky thread?

"At this stage it's a wise idea to do a quick check on the electrical condition of the smoothing/reservoir capacitor (see post #10). Take the capacitor out of circuit (ie disconnect electrically) and switch your meter to its highest Ohms range. Connect the meter across the tags and watch the reading"

Does the bold section actually mean "desolder and remove the capacitor"?
Just unsolder and disconnect all the wiring/component leads to it. You shouldn't need to remove it, unless it is a type directly mounted on and soldered to, the printed circuit board (PCB) - if a PCB is used.
dazzlevision is offline  
Old 26th Jan 2020, 6:04 pm   #12
Edward Huggins
Dekatron
 
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

This has a very early chassis, no PCB - it's all hard-wired.
__________________
Edward.
Edward Huggins is offline  
Old 26th Jan 2020, 10:05 pm   #13
GWR1971
Triode
 
Join Date: May 2016
Location: Colchester, Essex, UK.
Posts: 22
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

I've had the deck out just to see what's inside, and it all looks pretty clean for something that hasn't been used since the mid-60s. No obvious signs of bulging on the can or wax deposits under the transformer.

Obviously the valve is missing, and whoever was in here last left a shirt button (not pictured).

Just to confirm, is this definitely the same circuit as in post #5, even though there's no bulb or tone control on my Diploma? And does that mean that the missing valve is a UL41?
Attached Thumbnails
Click image for larger version

Name:	diploma1.jpg
Views:	131
Size:	95.4 KB
ID:	197822   Click image for larger version

Name:	diploma2.jpg
Views:	135
Size:	88.7 KB
ID:	197823  
GWR1971 is offline  
Old 26th Jan 2020, 10:13 pm   #14
TowerRadio
Hexode
 
Join Date: Mar 2008
Location: Bristol, UK.
Posts: 388
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

It looks like the original rectifier has been replaced with a silicon one,hence the RS wirewound dropper.Les.
TowerRadio is offline  
Old 26th Jan 2020, 10:17 pm   #15
GWR1971
Triode
 
Join Date: May 2016
Location: Colchester, Essex, UK.
Posts: 22
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Quote:
Originally Posted by TowerRadio View Post
It looks like the original rectifier has been replaced with a silicon one,hence the RS wirewound dropper.Les.
I'm very much a beginner to this sort of thing so... what component(s) are you referring to?
GWR1971 is offline  
Old 26th Jan 2020, 10:26 pm   #16
TowerRadio
Hexode
 
Join Date: Mar 2008
Location: Bristol, UK.
Posts: 388
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Very sorry,in the second picture the 2 items above the shiny aluminium can(the electrolytic capacitor) the grey lump with RS on it is a wire-wound resistor,the small black bit soldered to one end is a silicon rectifier.At some time the original rectifier(selenium,a pile of ali disks) failed and the 2 other bits took over the job of converting AC to DC in order to power the valve.Les
TowerRadio is offline  
Old 26th Jan 2020, 11:50 pm   #17
GWR1971
Triode
 
Join Date: May 2016
Location: Colchester, Essex, UK.
Posts: 22
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Thankyou

Is the old rectifier that thing to the right of it, that looks like a stack of thin metal discs?
GWR1971 is offline  
Old 27th Jan 2020, 12:24 am   #18
Michael Maurice
Moderator
 
Michael Maurice's Avatar
 
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,219
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Yes it is, normally when they fail, they give off a rather pungent smell.

The capacitor can is made up of three capacitors in one unit. I'm not sure about the type fitted in yours but i've had them fail in slightly later machines. I would replace them with a 32uF+32uF 500V capacitor and a single 47uF to replace he 50uF.

Also there is a capacitor which is 0.05uF, its almost certainly a paper wax type and it almost certainly requires replacement.

You can get these parts from Cricklewood Electronics.

As the deck is a single play deck, you will probably be ok with the idler wheel.
__________________
Forum Moderator

http://www.michaelmauricerepairs.co.uk/
Michael Maurice is offline  
Old 27th Jan 2020, 3:42 am   #19
GWR1971
Triode
 
Join Date: May 2016
Location: Colchester, Essex, UK.
Posts: 22
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

Quote:
Originally Posted by Michael Maurice View Post
The capacitor can is made up of three capacitors in one unit. I'm not sure about the type fitted in yours but i've had them fail in slightly later machines. I would replace them with a 32uF+32uF 500V capacitor
OK, so just discard the existing can rather than go through the process of trying to reform it?

Quote:
and a single 47uF to replace he 50uF
There's a 47uF 450V radial at Cricklewood - would that be the one?

The available sources of information point to the missing valve being a UL41. I've Googled and there seem to be plenty around, priced at about £14 plus shipping. Is that a typical price, and should I just buy one from eBay, or are there better, more highly-recommended sources?

Last edited by GWR1971; 27th Jan 2020 at 3:53 am.
GWR1971 is offline  
Old 27th Jan 2020, 9:30 am   #20
peter_sol
Octode
 
Join Date: Aug 2003
Location: Welwyn Garden City, Herts. UK.
Posts: 1,906
Default Re: Beginner wanting to restore a 1950s Dansette Diploma - where to start?

I'm not sure if that valve should be a UL41.
There is no locating skirt. How many pin holes are there and is there a gap between 2 of them?
Also measuring the heater voltage may help as it may be a UL84 or EL84.
peter_sol is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 6:21 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.