Re: draining filter caps

As far as I can tell, my response was to Mike Schway, and I
wasn't dissing anyone besides that prissy RS ***, who
copped attitude over a perfectly good answer. Besides -
everyone knows I kiss ass to get business, right? Must
be true, Blumb the Dumb sez so...and I don't give a ***. ;-)
So consider your ass kissed. No hard feelings. ;-)

Lord Valve
Expert (sorry, still no ***. I'm workin' on it, prolly stay up all
night...)

This is Top Post #20,003. Baboon Squad, please obsess.
Toadies, set your Secret Decoder Rings to 7581ASS for
tomorrow's marching orders.

And so forth...



Christopher J. Keklak wrote:

You're not the *only* one Willie. Just so happens some customers are
so damn picky they want those ABradley CC's, which I do not like
except in certain positions of the AB763 circuit, such as 100K 1W
plate load resistors, input jacks, and others. I was going to mention
equalizing the voltage between the two B+ filter caps in series so
that one cap doesn't *see* more voltage than the other, but just plain
forgot to mention it. Thank God I am not perfect all the time like
you. I wish you wouldn't shoot the messenger who buys great tubes from
you unless it is a serious matter. But, of course, who gives a ***
about customers, right? :^)
"Lord Valve" <detritus@xxxxxxxxxxxxx> wrote in message
news:4610F9B5.7470E475@xxxxxxxxxxxxxxxx


Mike Schway wrote:

In article <oKQPh.20491$uo3.737@xxxxxxxxxxxxxxxxxxxxxxxxxx>,
"Christopher J. Keklak" <keklakoh@xxxxxxxxxxxxx> wrote:

In a fender SR, TR, e.g., take the cap can off. The first two
filter
caps on the left (B+) each has a 200K/220K resistor installed in
parallel with each cap. I like to use 2 watter carbon comps,
measuring
with my Fluke just to ensure correct values. You want the
resistors to
be the exact same value. We won't go into that further.

You can either piggyback each resistor to the cap leads, or more
commonly one uses existing eyelets in the case of the SR and TR
(I
install them on DR's since they're not there). Take a look at a
Super
Reverb AB763 schematic and you will see them alongside the "B+"
caps.
Piece of cake.

These resistors were originally intended not to bleed off voltage,
but
to insure that each first-stage cap (in series) see the same
voltage.
BTW, I like to use metal oxide...less value drift over time.
Matching is
important.

Holy ***!

Well, *someone*on this thread knows his ***. (Besides me.)
And I *always* change those to MO types. Folks'd be surprised
how much noise those nasty old CCs make, even as dividers
in the HV supply.

Not all Fenders from the BF/SF era used these resistors. You can't
just
assume that since it's a Fender you can just dive in there. A
particular "surprise" to me was the first time I worked on a
Vibrolux
Reverb. OUCH! ;-)

That's what discharge probes are for.

I've been using my 1K/3W probe for over 20 years.
Changed the wire and the heatshrink tubing a
couple of times, but it's still the same resistor.
Of course, *everyone* knows a 1K/3W resistor
will go up in smoke if you put more than 55 volts
across it.

Right?

Right.

So that's why I dont give a ***. Fancy that...


Lord Valve
Expert (still not giving a Mile-High *** in Denver)






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