Dual CS 505-3 Restoration - UK Vintage Radio Repair and Restoration Discussion Forum

richhutch · 16th Jan 2021, 12:51 pm

Hi guys.
I’m a newbie and this is my first post. Have just bought a Dual CS 505-3 on Gumtree for a ridiculous £10. Is in very decent nick although not actually working but think that might just be a new belt. Missing one of the sub-chassis screws and unknown AT cartridge fitted. Any tips?

richhutch

PaulR · 16th Jan 2021, 1:02 pm

Can you give a bit more information? Does it do anything when switched on? Does the motor run?

Michael Maurice · 16th Jan 2021, 1:11 pm

One of the common faults is dried out grease which prevents a lever operationg the power switch.

ajgriff · 16th Jan 2021, 1:48 pm

Hello and welcome. My first step would be to do some research (Google). Find the owner's and service manuals although you might have to make do with the 505-2 service manual which should be close enough however.

The missing screw may just be a manufacturer's transit/packing fixing which will have been discarded long ago as it's not really needed. Again the manuals, which might be in German, will help clarify.

To check the belt you'll need to remove the platter. On the 505-2 this involves removing the Befestigungsscheiben or attachement plate. Be careful as it's a twist fit on the 505-2. If you try to lever it off it will break as it's plastic. The 505-3 might be different of course. Similarly the 505-2 has a second belt accessible from underneath the deck for the pitch adjustment mechanism. If it's broken (they often are) the platter won't rotate.

I wouldn't worry about the cartridge at this stage as long as it's got its stylus and isn't obviously damaged. Just get the deck working in the first instance.

Alan

Michael Maurice · 16th Jan 2021, 2:00 pm

The pitch belt wont stop the platter rotating, it will just stop you fine adjusting the speed.

ajgriff · 16th Jan 2021, 2:07 pm

Quote:

Originally Posted by Michael Maurice

The pitch belt wont stop the platter rotating, it will just stop you fine adjusting the speed.

My memory's obviously letting me down, sorry if I got that wrong.

Alan

Beobloke · 16th Jan 2021, 2:22 pm

Depending on your level of skill, it’s also worth replacing the 4 (might be 5...) components on the small PCB that runs the motor. The dropper resistor is under-rated and gives off some funny smells at it gets old and the mains suppression capacitor has a tendency to explode! The latter won’t do any damage and the deck will still work, but it’ll make you jump!

Component kits are readily available on eBay for around £10 and they only take half an hour to change if you’re handy with a soldering iron.

On the main turntable drive belt front, be wary of the replacement offered by Malvern Audio. The last one I had from them was much, much too tight. Their toothed speed belt fits perfectly, though.

ajgriff · 16th Jan 2021, 2:46 pm

There are a couple of good videos on the internet showing how to replace the belts.

Alan

richhutch · 16th Jan 2021, 7:03 pm

Thanks for all your input guys. Will be able to answer many of your questions once I get working on it, stating with platter off to see if it is a broken belt/no belt issue. Brilliant to know there might be some expert help out there.

16th Jan 2021, 12:51 pm	#1
richhutch Triode Join Date: Jan 2021 Location: Glasgow, Scotland, UK. Posts: 12	Dual CS 505-3 Restoration Hi guys. I’m a newbie and this is my first post. Have just bought a Dual CS 505-3 on Gumtree for a ridiculous £10. Is in very decent nick although not actually working but think that might just be a new belt. Missing one of the sub-chassis screws and unknown AT cartridge fitted. Any tips? richhutch

16th Jan 2021, 1:02 pm	#2
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Dual CS 505-3 Restoration Can you give a bit more information? Does it do anything when switched on? Does the motor run? __________________ Paul

16th Jan 2021, 1:11 pm	#3
Michael Maurice Moderator Join Date: Feb 2006 Location: Wembley, Middlesex Posts: 7,223	Re: Dual CS 505-3 Restoration One of the common faults is dried out grease which prevents a lever operationg the power switch. __________________ Forum Moderator http://www.michaelmauricerepairs.co.uk/

16th Jan 2021, 1:48 pm	#4
ajgriff Nonode Join Date: May 2004 Location: Halifax, West Yorkshire, UK. Posts: 2,587	Re: Dual CS 505-3 Restoration Hello and welcome. My first step would be to do some research (Google). Find the owner's and service manuals although you might have to make do with the 505-2 service manual which should be close enough however. The missing screw may just be a manufacturer's transit/packing fixing which will have been discarded long ago as it's not really needed. Again the manuals, which might be in German, will help clarify. To check the belt you'll need to remove the platter. On the 505-2 this involves removing the Befestigungsscheiben or attachement plate. Be careful as it's a twist fit on the 505-2. If you try to lever it off it will break as it's plastic. The 505-3 might be different of course. Similarly the 505-2 has a second belt accessible from underneath the deck for the pitch adjustment mechanism. If it's broken (they often are) the platter won't rotate. I wouldn't worry about the cartridge at this stage as long as it's got its stylus and isn't obviously damaged. Just get the deck working in the first instance. Alan

16th Jan 2021, 2:00 pm	#5
Michael Maurice Moderator Join Date: Feb 2006 Location: Wembley, Middlesex Posts: 7,223	Re: Dual CS 505-3 Restoration The pitch belt wont stop the platter rotating, it will just stop you fine adjusting the speed. __________________ Forum Moderator http://www.michaelmauricerepairs.co.uk/

16th Jan 2021, 2:22 pm	#7
Beobloke Heptode Join Date: Oct 2007 Location: Southampton, Hampshire, UK. Posts: 821	Re: Dual CS 505-3 Restoration Depending on your level of skill, it’s also worth replacing the 4 (might be 5...) components on the small PCB that runs the motor. The dropper resistor is under-rated and gives off some funny smells at it gets old and the mains suppression capacitor has a tendency to explode! The latter won’t do any damage and the deck will still work, but it’ll make you jump! Component kits are readily available on eBay for around £10 and they only take half an hour to change if you’re handy with a soldering iron. On the main turntable drive belt front, be wary of the replacement offered by Malvern Audio. The last one I had from them was much, much too tight. Their toothed speed belt fits perfectly, though.

16th Jan 2021, 2:46 pm	#8
ajgriff Nonode Join Date: May 2004 Location: Halifax, West Yorkshire, UK. Posts: 2,587	Re: Dual CS 505-3 Restoration There are a couple of good videos on the internet showing how to replace the belts. Alan

16th Jan 2021, 7:03 pm	#9
richhutch Triode Join Date: Jan 2021 Location: Glasgow, Scotland, UK. Posts: 12	Re: Dual CS 505-3 Restoration Thanks for all your input guys. Will be able to answer many of your questions once I get working on it, stating with platter off to see if it is a broken belt/no belt issue. Brilliant to know there might be some expert help out there.