WD88VA noise

[bob orbell]

Phil, you need to put a star washer, preferably external type, in-between the top cover and the transformer and on the under side, inside, contacting the chassis, then the earth wire with a ring terminal, and do that bolt up tight, but dont bust or strip the bolt. I know the mains transformer has it's own earth wire, but do the same here. If you use all the rear bolts you will not see the gap that the washers make.BOB

[david]

Hi Phil,
i had to connect the earth wires under the top chrome caps to stop my problem.
David

[bob orbell]

That's what the star washers are for David to make a good electrical connection. BOB

[Riggers]

hi all
Still getting the annoying tick every 4.3 seconds to be exact, (I timed it with my iphone stopwatch). I have inserted 1 star washer underneath each Tx cover and all have leads to the earth post from a mounting bolt at the base. I still think the mains Tx is the issue as continuity from on top of mains TX cover to earth post is there, but not as good as with the opTx's.

One point of difference from the mains Tx and the opTx is that the mains Tx sits on rubber/plastic grommet/washer (the opTX bolt direct to the chassis) and the earth lead inside the chassis that connects from one of the mounting bolts cannot contact the chassis where the Tx is mounted. I'm thinking of trying a second wire connecting a second bolt from the mains Tx to the chassis earth post and see how I go.
Cheers
Phil.

[Riggers]

Hi Gents (and ladies)
SUCCESS!!!!!!!!!!!!!!!!!!!!
I now how no annoying "tick" noise every few seconds. My WD88VA is now after a few test runs performing flawlessly. The last time I had it on the operating table I performed a couple of tasks: Added a second earth lead from a mounting bolt of the mainsTx to the chassis earth post; resoldered 2 of the diodes on the HT board, (I had previously measured all voltages as per spec. but I did this as these components were soldered to the centre holes on the tag boards and were originally soldered with the iron approaching from the underside- the joints looked ok visually but perhaps a ? over their effectiveness; I also replaced a couple of bolts that mounted the choke (i was short 2 bolts in the kit which matthew promptly sent over but in the meantime i had substituted 2 zinc coated bolts/nuts). i have no idea which of these minor tweaks did the trick but the end result is now beautiful music.

Thanks all for your help and consideration.
Cheers
Phil.

[bob orbell]

Glad you have got it sorted Phil, it would have been nice to say exactly what the problem was, my money goes on the mains transformer cap not earthed, hey-ho. BOB

[John Caswell]

Hi all,
Most unlikely to be the soldering of the diodes, much more likely to be the choke metalwork earthing and/or the power tx covers.
Either way glad you have it sorted Phil, well done!

John

[Riggers]

Hi All
Just a post script to my earlier issue. I have been operating my Wd88VA apparently with no problems 5-6 weeks until tonight, where the amp was running for a little over an hour when I detected all of a sudden a slight rustling noise or hiss from right channel only. From checking other posts I believe I should be looking for valve fit (corrosion on pins etc) or the dreaded poor solder joint. Does the fact that the noise only develops after an hour or so have any significance?
Cheers
Phil.

[John Caswell]

Hi Phil,
Try this. With the amp off pull each of the small valves out and replace several times, thereby cleaning the pins/sockets. Then try again. If it still persists try swapping the 5687 from side to side to see if the rustle follows. If it does - noisy 5687. If not replace the ECC83 with another if you have it, fault goes - noisy ECC83. If not do the same with the KT88.
If none of these cure the problem then you possibly have a poor solder joint on ECC83/5687 circuits or a noisy resistor ditto

John

[Riggers]

Thanks John
Will do as instructed and report back later in the week.
Otherwise I have to say this is the best sounding amp I have owned and hopefully I can sort this minor gremlin.
Phil.