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 28th Apr 2023, 6:40 pm   #161
FrankSinatra
Pentode
 
Join Date: Mar 2020
Location: Halesowen, West Midlands, UK.
Posts: 112
Default Re: Heirloom item help please

Seems the sound distortion issue was a simple speaker problem that seems to be corrected now so not a more complicated problem.

I finally talked myself into taking out the chassis for photographs underneath so the team here could give some advice hence the discussion now on apparent Hunts moldseals capacitors in place that everyone suggests should be replaced immediately.
FrankSinatra is offline  
Old 28th Apr 2023, 8:47 pm   #162
Lucien Nunes
Rest in Peace
 
Join Date: Apr 2008
Location: London, UK.
Posts: 2,508
Default Re: Heirloom item help please

Quote:
"it sounds great again" - you seem to have moved on to changing some of the caps. What really needs to be done to this now then?
That was my suggestion. There are exactly two Moldseals in the chassis; the coupling caps to the EL84s. Seeing as the OP has gotten so far along with this gram and is all set to start enjoying his music on it, there seems perfect sense in purging these likely troublemakers while the back is still off. I'm all in favour of leaving as much original material in situ as possible for historical reasons, but not these two, surely?
Lucien Nunes is offline  
Old 22nd May 2023, 7:07 pm   #163
FrankSinatra
Pentode
 
Join Date: Mar 2020
Location: Halesowen, West Midlands, UK.
Posts: 112
Default Re: Heirloom item help please

Just dropped it off at a helpful local members place to get them sorted and a line in thanks for your advice in this matter all.
FrankSinatra is offline  
Old 23rd May 2023, 5:55 pm   #164
Silvered_Mica
Pentode
 
Silvered_Mica's Avatar
 
Join Date: Aug 2003
Location: Halesowen, West Midlands, UK
Posts: 125
Default Re: Heirloom item help please

Thanks for bringing it round

After powering up it was found that the left channel seemed slightly weak and all the balance control was doing was changing the level of the right channel so I though there was something wrong around the balance control.
Just had the chassis out and it seems to have the most unusual balance configuration (see diagram). I've not seen it done like this before, it really grabbed my eye only seeing two connections on the balance pot. Surely that 150K resistor should be 250K or am I missing something?

I will keep you all posted.
Attached Thumbnails
Click image for larger version

Name:	IMG_6443.jpg
Views:	93
Size:	55.3 KB
ID:	278637  
__________________
Trust Me, It's a Magic Iron (∩ ͡° ͜ʖ ͡°)⊃━☆゚. * ・ 。゚, 📻📺🦔📡
Silvered_Mica is offline  
Old 4th Jun 2023, 11:50 am   #165
Silvered_Mica
Pentode
 
Silvered_Mica's Avatar
 
Join Date: Aug 2003
Location: Halesowen, West Midlands, UK
Posts: 125
Default Re: Heirloom item help please

OK all done, 4 resistors and 2 capacitors changed out.
All voltages now in there ball parks.
All valves test strong.
Auxiliary socket and ground loop isolator fitted.
Rewired the band change switch so that short-wave is now auxiliary position.
Done a few safety insulation tests and blew the dust out.
Partly re-wired for safety.
Made some speaker adapter plates and replaced speakers
(as old speaker magnets partly trapping speech coils).
Done about 5 hours of soak test with no issues.

Power transformer is running a little hot (no excessive current consumption)
so might need changing in time.
Fortunately it's a 250-0-250 with 6.3v so wouldn’t be difficult to find a suitable replacement.
__________________
Trust Me, It's a Magic Iron (∩ ͡° ͜ʖ ͡°)⊃━☆゚. * ・ 。゚, 📻📺🦔📡
Silvered_Mica is offline  
Old 4th Jun 2023, 5:41 pm   #166
FrankSinatra
Pentode
 
Join Date: Mar 2020
Location: Halesowen, West Midlands, UK.
Posts: 112
Default Re: Heirloom item help please

Great job done thanks peace of mind and sounds great.

Thanks for all advice on here to this point.
FrankSinatra is offline  
Old 4th Jun 2023, 7:44 pm   #167
Techman
Dekatron
 
Techman's Avatar
 
Join Date: Nov 2009
Location: Lincolnshire, UK.
Posts: 4,958
Default Re: Heirloom item help please

Quote:
Originally Posted by Silvered_Mica View Post
Power transformer is running a little hot (no excessive current consumption)
so might need changing in time.
I doubt that there's anything wrong with it if no additional load has been added. A lot of these mains transformers run with the laminations almost too hot to touch, it's just how they are. Even a single shorted turn takes a transformer out in no time at all and you'd soon know about it if that was the case, so if the transformer hasn't been given any significant extra stuff to supply current to, then I wouldn't worry about it, I'm sure it'll be fine.
Techman is offline  
Old 5th Jun 2023, 3:42 pm   #168
Silvered_Mica
Pentode
 
Silvered_Mica's Avatar
 
Join Date: Aug 2003
Location: Halesowen, West Midlands, UK
Posts: 125
Default Re: Heirloom item help please

It seems to be running a bit warmer than normal however it lives next door to a thermionic rectifier and one of the output pentodes so that’s probably why it seems a little warmer than it should be due to heat transfer through the chassis.

The balance control makes more sense now, it has an off-set potentiometer so when set to halfway point (12 O,clock position) this is not in the middle of the pot.
__________________
Trust Me, It's a Magic Iron (∩ ͡° ͜ʖ ͡°)⊃━☆゚. * ・ 。゚, 📻📺🦔📡
Silvered_Mica is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 12:09 pm.


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.