WAD 6550 new-bad warm-up noise

[Johnfromnorwich]

Originally Posted by soulminer

There is a Maplin in Llandudno, John.

Cheers

Ah yes! The worst Maplin on earth! There must be a league table for these things somewhere. Last time I went they didn't even have any RCA plugs and I bought their last two female XLRs (I needed three of course). I'm off to Leeds next weekend so I may try the one there instead - assuming I need parts.

[Greg.]

Hi John,

You do have several active forum members who live farely close to you who I know would be able to help. It would be good if they would chip in, in accordance with what historically has always been this forums generous ethos offering help to others. Have a hunt through the members list. You will find several in your area who you could 'Private Maessage' requesting help.

Likewise, John Caswell (Dr John) is a frequent poster and also moderator. You'll find his contact from a recent post or the membership list. He's a top grade valve electronics engineer and without doubt will see you right but realise his work is also his income so whilst he happily advises here or over the phone, if you post your amp to him for attention, there naturally will be a reasonable charge.

Best wishes,

Greg

[Johnfromnorwich]

Originally Posted by Greg.

Hi John,

You do have several active forum members who live farely close to you who I know would be able to help. It would be good if they would chip in accordance with what historically has always been this forums generous ethos offering help to others. Have a hunt through the members list. You will find several in your area who you could 'Private Maessage' requesting help.

Likewise, John Caswell (Dr John) is a frequent poster and also moderator. You'll find his contact from a recent post or the membership list. He's a top grade valve electronics engineer and without doubt will see you right but realise his work is also his income so whilst he happily advises here or over the phone, if you post you amp to him for attention, there naturally will be a reasonable charge.

Best wishes,

Greg

Thanks for that. I'll have a look. Actually, the guy who installed my boiler is a WAD owner and is more or less directly responsible for me buying one. I think he's a very busy man though and I'm not even sure if he posts on here.

[pre65]

Originally Posted by Johnfromnorwich

Thanks for that. I'll have a look. Actually, the guy who installed my boiler is a WAD owner and is more or less directly responsible for me buying one. I think he's a very busy man though and I'm not even sure if he posts on here.

Don't think Paul B goes that far from home "on the job"


Philip

[acorn]

John

Caps can show no sign of stress and can still be leaky. I believe they are of the printed circuit type, I will have to look them up, yes by changein them both of them will be the only way to make sure thats not the problem even a capacitor meter wont tell you the full story, capaciters can be very fikle indeed one moment fine then trouble some are even self repairing. The choke is under neath the chassis one black wire in and the other out and is fitted between the first power electrolytic and the second power electrolytic.

Acorn

[steve]

If you get over to the Liverpool area I would be happy to help. Built and modified several WAD kits and now design my own valve equipment. I had a similar problem caused by the original 5U4 rectifiers accompanied by a brief blue flash - cured by changing to a 5U4GB. (Only started to happen after about 6 months after the initial build - really frightened the wife initially). Could really do with seeing the problem though.

[steve]

John,

something else that may help assuming you don't actually have a fault with the amp is to fit a current inrush limiter between the IEC connector and the mains transformer. (Goes in series in say the live connection). Maplin used to sell them but if they have stopped you can get them from most mail order component suppliers. These devices effectively slow start the amp and prevent transformer thumps at switch on (by limiting the current flow until the device warms up fully, typically a few seconds). They are often mentioned on the forum where fuses are blowing frequently.

[Johnfromnorwich]

Originally Posted by steve

If you get over to the Liverpool area I would be happy to help. Built and modified several WAD kits and now design my own valve equipment. I had a similar problem caused by the original 5U4 rectifiers accompanied by a brief blue flash - cured by changing to a 5U4GB. (Only started to happen after about 6 months after the initial build - really frightened the wife initially). Could really do with seeing the problem though.

That's a very kind offer. Liverpool is easily 'doable' - hour and half at most. I'm away this weekend but I'm usually able to be pretty flexible. If you're happy to help, PM me a couple of possible dates and I'll try and come up with a plan. The amp actually came from Birkenhead in the first place.

Cheers

John