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

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Radio (domestic)

Notices

Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only.

Reply
 
Thread Tools
Old 12th Oct 2017, 3:42 pm   #1
cernem1alt
Triode
 
cernem1alt's Avatar
 
Join Date: Sep 2017
Location: Dorchester, Dorset, UK.
Posts: 16
Default Bush DAC90A goes quiet

Work done so far usual Caps changed new bulbs, perished wiring replaced checked my soldering all ok

Now after a while the set goes quiet where should I look? I am thinking resistors

However quick flick of the waveband switch jumps it back for a while


Mike M1ALT
"Live Chassis precautions observed "
cernem1alt is offline   Reply With Quote
Old 12th Oct 2017, 4:15 pm   #2
kalee20
Dekatron
 
Join Date: Feb 2007
Location: Lynton, N. Devon, UK.
Posts: 4,028
Default Re: Bush DAC90A goes quiet

What about a slow flick of the waveband switch?

A quick flick could shock something elsewhere on the chassis which is dodgy, into recovering its contact. A slow flick (if that's not a contradiction in terms!) is unlikely to do so, except the contacts of the switch itself.

Does this happen when left on LW and on MW, or just one waveband (which?)?
kalee20 is offline   Reply With Quote
Old 12th Oct 2017, 4:43 pm   #3
cernem1alt
Triode
 
cernem1alt's Avatar
 
Join Date: Sep 2017
Location: Dorchester, Dorset, UK.
Posts: 16
Default Re: Bush DAC90A goes quiet

Slow flick or quick flick makes no difference, jumps it back, it is on LW where this happens.
__________________
"Live Chassis precautions observed "
cernem1alt is offline   Reply With Quote
Old 12th Oct 2017, 4:49 pm   #4
ukcol
Dekatron
 
ukcol's Avatar
 
Join Date: May 2003
Location: Harlaxton, Lincolnshire, UK.
Posts: 3,152
Default Re: Bush DAC90A goes quiet

The 110pF capacitors in the IF transformers can give this symptom. I have had it with a DAC10 and heard reports of it with the DAC90A.
__________________
Best Regards, Colin McLaughlin
BVWS Member
ukcol is offline   Reply With Quote
Old 12th Oct 2017, 5:45 pm   #5
Boater Sam
Nonode
 
Boater Sam's Avatar
 
Join Date: Dec 2013
Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
Posts: 2,006
Default Re: Bush DAC90A goes quiet

Is there any screened lead around the volume control or top cap connectors that is perished inside and breaking down? Had this recently with a Murphy 104, same symptoms.
__________________
Boater Sam.
BVWS Member
Boater Sam is offline   Reply With Quote
Old 12th Oct 2017, 7:33 pm   #6
cernem1alt
Triode
 
cernem1alt's Avatar
 
Join Date: Sep 2017
Location: Dorchester, Dorset, UK.
Posts: 16
Default Re: Bush DAC90A goes quiet

Re wired C17 tone cap and C22 replaced wires with better screened now has case off sat on bench behaving itself listening to Radio 4 LW so we shall see.......
__________________
"Live Chassis precautions observed "
cernem1alt is offline   Reply With Quote
Old 12th Oct 2017, 9:00 pm   #7
cernem1alt
Triode
 
cernem1alt's Avatar
 
Join Date: Sep 2017
Location: Dorchester, Dorset, UK.
Posts: 16
Default Re: Bush DAC90A goes quiet

Problem solved Me thinks ......a dry solder joint that is going open circuit as the set warms up and then remakes again once the set has cooled down
__________________
"Live Chassis precautions observed "
cernem1alt is offline   Reply With Quote
Reply

Thread Tools



All times are GMT. The time now is 3:17 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 - 2017, vBulletin Solutions, Inc.
Copyright ©2002 - 2017, Paul Stenning.