Fender reissue deluxe reverb PSU caps

[Brian Roth]

While geeetar <g> amps are not my main line of work, I've serviced many in the ....ahhh....two or three years <LOL> of my professional life. 

This Reissue Deluxe came in Ye Olde Shoppe recently, looking all Minty Fresh, yet with a screaming amount of mains hum:

ampwares.com/schematics/65_Deluxe_Reverb_RI.pdf

Page 7 of the PDF has the schemo.  Finding around 150 VAC RMS on top of low B+ at the Standby switch,  some quick checks revealed that C32 (47 uF at 500 VDC) was open circuited....a 0 uF cap.

My quandry ...  I have certainly seen series connected "stacked" lytics in various higher voltage applications.  But, they were always equal value lytics in series,  with equal value resistors in parallel with each cap.

This bugger puzzles me, since none of the ancient Deluxe schemos ever used anything like this.  Why?

Anyway, I'll toss in a new cap and move on.  Oh yes...the lytics are Illinois brand, which I have always associated with crap/junk.  Checking online sources and other info, I THINK I will use a F&T brand replacement unless someone warns me otherwise.

Thanks!

Bri

 

[PRR]

Illinois caps have been very good to me for many decades. And it IS a geetar amp, not a broadcast console.

Wow. Musta been a supply problem the day they compiled the BOM.

And it's only a lousy 396V.

And oddly they have 22uFd 500V further down. Why not two 22u500V parallel?

Me, if 35-40uFd 450V was not at hand, I'd do it right with two 80uFd 300V caps series. Use two 100K 1W resistors with that.

 

[mjrippe]

Hi Brian,

I've got a Hot Rod Deluxe in with a similar problem.  It has three "ic" (Illinois?) brand caps and one Sprague Atom.  I just ordered all four F&T axials to be on the safe side ;-)

Mike