Hiya Keith,

Nice thing about bottle gear, easy to spot the fault and get to. Seeing R6
cooked (screen grid resistor?) why did it get mucho grid current I'm
thinking? It may be worth keeping an eye on it even if you've swapped out
the tube. But I think possibly that coupling cap was leaky giving +ve to G1
driving plate current hard and screen grid current burning R6 - Good job
Keith you've got the problem all sorted for Crimbo :-)
Cheers,

Mike

"Keith G" wrote in message
...

Well, don't know about you lot, but I've spent the day sorting out my
valve
gear before Little Santa takes all the 'homeless' (no boxes) munchkins off
for their Xmas holdays - see

http://www.apah69.dsl.pipex.com/keit...w/holidays.jpg

Having painstakingly assembled the requisite Mullies, Svets and JJs
(including a quad of EL34s that I have no use for*) from Jim Fish of
Wilson
Valves -

http://www.flashbacksales.co.uk/wils...es/wvindex.htm

(utterly recommended) and some very nice little Mazdas from ebay, I have
'Mullied out' my EARs and they are now on top song. (They drive my Dynaco
Mk
IIIs and the sound makes me wonder what the Yanks have been up to for the
last 30+ years!!)

Next, I Mazda'd, Mullied and JJ'd my little AI 400 and it is now fighting
well above its weight - at 12 or 15 wpc (no idea which) you could be
forgiven for thinking it was an 85-100 wpc SS jobbie, I promise you! ;-)

Then it was time to take a look at Johnny WAD. (This little bleeder's been
munching glass lately!)

First up, rip his guts out all over the dining table (note the ****ty
table - Swim wanted to buy one of they flash Eytie tables from JL last
year,
I said 'forget it, moi sweet'!) see

http://www.apah69.dsl.pipex.com/keit.../the%20job.JPG

T'werent hard to find the casualties - R6 and R32, see

http://www.apah69.dsl.pipex.com/keith_g/show/burn1.JPG

and http://www.apah69.dsl.pipex.com/keith_g/show/burn2.JPG

Swapped 'em out (by some miracle I had just the right two resistors spare
and no others!), slapped it back together and fired it up.

Ha bloody ha! Within a minute one of the 6550Cs (ain't paying daft money
for
KT88s if all they are going to do is tear my board up!) is glowing red up
the middle. At this stage my thoughts are along the lines of 'far king
valves, who in his right mind would bother with 'em?' Get the bottom off
again and whaddaya know? - One of the (coupling?) caps C11 is slightly
bellied! (Anyone with even half a clue about this sort of stuff would have
checked them all a damn sight more careful than I did!)

So it's the board out this time and, courtesy of a ciggie packet....

(see http://www.apah69.dsl.pipex.com/keit...w/ciggies1.jpg)

....I didn't have to break any connections. Swapped the cap - one of three
I
had as spares (my total remaining spares, I might add!) and reassembled it
certain in the knowledge I had fixed it now. (How did I know that? - Easy,
by now I had burnt myself with the fekkin' soldering iron! Always a good
sign! :-)

Been on an hour now - after a few minutes to let it settle, I swapped the
rest of the minis for my last two precious Mullies (CV4003s) and it's
sounding better than ever. (And that ain't ****e, believe you me! ;-)
Ironic ain't it? - The cost of the spares is 1 x 25p and 2 x
14p........!!!

While I'm on, here's a picture of the board

http://www.apah69.dsl.pipex.com/keith_g/show/board.JPG

to give you an idea of how bloody fiddly it is and, finally, a close-up of
my soldering which I don't think is too bad for a clueless **** like me
who
doesn't get to do nearly enough of it!

http://www.apah69.dsl.pipex.com/keit.../soldering.JPG

Why am I posting all this guff? - Well, I've enjoyed the day, the sound
I'm
getting from the kit now is entirely superb and I just thought it might be
interesting as well as encourage/put off a few people from trying The
Wonder
Of Valve Amplification! :-)


*Four EL34s that I don't need? Looks like I'll have to do summat raucous
in
the new year!


Merry Xmas one and all and I hope the New Year is a blinder for everyone
here!

;-)


PS. I'd like a couple of dozen more hits on the uk.rec.audio.* page
http://www.apah69.dsl.pipex.com/ to get us up to the 10K mark in the first
year!