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-   -   Tandberg Huldra 8 valve failure (https://www.vintage-radio.net/forum/showthread.php?t=132315)

roverp6 25th Feb 2017 4:56 am

Re: Tandberg Huldra 8 valve failure
 
I had the black probe attached to the chassis, where should i have put the black probe?

PJL 26th Feb 2017 12:14 am

Re: Tandberg Huldra 8 valve failure
 
Try measuring the EF89 heater AC voltage with the new meter.

Do the two 'security lamps' show a low resistance? Are you waiting for the replacement fuse?

roverp6 26th Feb 2017 3:21 am

Re: Tandberg Huldra 8 valve failure
 
Yes i just ordered some fuses from England, where i live i cant get anything that is close to the right fuse..............very much a backwater. i ordered slow blow 2A 500v 6.2x30mm closest i could find to the original 2000mA 5x30mm
i also have checked the 2 other fuses that look like lamps S5/S6 12v 18w Osram No 6475 they have continuity. will work on the new measurement on the EF89..........."security lamps" are you referring to sikringslampe translated to fuse lamp?

clive

roverp6 27th Feb 2017 1:47 am

Re: Tandberg Huldra 8 valve failure
 
2 Attachment(s)
all the reading from 4 valves are 6.6v on sockets 4 and 5 the only valve i didn't measure was the magic eye. the fuse S1 has blown should i change out capacitors C704 and C705?
Clive

Boater Sam 27th Feb 2017 2:32 am

Re: Tandberg Huldra 8 valve failure
 
Why would you want to? They are most unlikely to be faulty, is this a guess or just something to do?

roverp6 27th Feb 2017 3:30 am

Re: Tandberg Huldra 8 valve failure
 
i only mentioned it because i have new replacements and is connected to the blown fuse, and it was a guess.

'LIVEWIRE?' 27th Feb 2017 9:35 am

Re: Tandberg Huldra 8 valve failure
 
The fault is more likely to be the rectifier (D701), smoothing capacitors (C11), or in the transistor amplifer, which is powered from the 33vDC supply. Putting an ammeter (on AC Amps range) if your meter has one, across the S1 contacts (without a fuse in place) and measuring the current before and after disconnecting suspect components will indicate which part is the culprit, which is unlikely to be C704 or 705.

PJL 27th Feb 2017 10:01 am

Re: Tandberg Huldra 8 valve failure
 
You might blow the fuse in the meter so I would suggest you use a lamp limiter when you do this. As a fault has already been repaired in the HT PSU, I am hoping it is just the fuse that has gone.

roverp6 7th Mar 2017 5:01 pm

Re: Tandberg Huldra 8 valve failure
 
taking a time out until i get the fuses, giving the experts here a break :zzz:


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