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-   -   Ekco U332 (https://www.vintage-radio.net/forum/showthread.php?t=182635)

Dorian27 8th Aug 2021 3:54 pm

Ekco U332
 
The above radio on switch on for about 3 to 4 min the volume is high as normal but after 3 to 4min it just goes right down low in one go not slowly but immediately. Can any one help? Don't know where to look. I have changed the coupling capacitor. But still drops as I said not gradually but immediately. Any one now what it might be? The volume when it goes down is still audible but if you want more there is none.

Station X 8th Aug 2021 4:09 pm

Re: Ekco U332
 
Have you monitored the HT voltage during warm up?

Dorian27 8th Aug 2021 5:45 pm

Re: Ekco U332
 
No i havent not sure how to do that

Dorian27 8th Aug 2021 7:41 pm

Re: Ekco U332
 
Can any one tell me how to check the ht voltage if it goes down please

ms660 8th Aug 2021 8:27 pm

Re: Ekco U332
 
Between the +ve of C27 and chassis and between the +ve of C26 and chassis.

Approx. 160 Volts DC and approx. 94 Volts DC respectively according to the service info when supplied with 240 Volts mains.

Lawrence.

Dorian27 9th Aug 2021 11:04 am

Re: Ekco U332
 
Hi i have taken HT readings go steady as follows C27 is 196/7v and C26 is 90/91v

ms660 9th Aug 2021 11:18 am

Re: Ekco U332
 
Output valve voltages?

Lawrence.

Dorian27 9th Aug 2021 4:10 pm

Re: Ekco U332
 
Pin 9 is 44v Pin6 is 198v

ms660 9th Aug 2021 4:21 pm

Re: Ekco U332
 
Output valve voltages?

Lawrence.

Dorian27 9th Aug 2021 4:26 pm

Re: Ekco U332
 
Not sure what you mean by value voltage

ms660 9th Aug 2021 4:30 pm

Re: Ekco U332
 
Quote:

Originally Posted by Dorian27 (Post 1396985)
Not sure what you mean by value voltage

Neither do I because I didn't say "value"

Try valve electrode voltages.

Lawrence.

Station X 9th Aug 2021 4:32 pm

Re: Ekco U332
 
1 Attachment(s)
Lawrence said output valve voltages.

The output valve is V3B, the pentode section of a UCL82.

Pin 6 Anode.
Pin 7 Screen Grid.
Pin 2 Cathode.
Pin 3. Control grid.

Valve pins number clockwise from the gap or spigot when seen from under the chassis.

The DC voltages should be measured with respect to (WRT) chassis.

All this is in the manufacturer's service sheet, which is where I got it from.

EDIT. Posts crossed.

ms660 9th Aug 2021 4:35 pm

Re: Ekco U332
 
By output valve I mean the UCL82 as a whole....how hard can it be to measure the electrode voltages.....

Lawrence.

Station X 9th Aug 2021 4:52 pm

Re: Ekco U332
 
Very difficult I'd say. It seems to be the very last thing some repairers and restorers want to do. Far easier just to change components in case they're faulty.

I'm an old school dinosaur who adopts a logical approach to fault finding. Meter before soldering iron!


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