63 Deluxe questions

[kendogg]

I have a 63 Deluxe model AA763 in serious need of some TLC, and I have some questions. The tubes have been replaced, but I still need to tension the sockets as they are all loose, which I assume is causing intermittent noise. The filter caps are also fairly new, replaced last year, and have less than 10 hrs on them.
Anyhow, I'm thinking that while I've got the thing open, I need to replace all the electrolytic caps inside. I'm only 15 minutes from Antique Electronics, so I'm hoping to get all my parts there. The 25uf 25V capacitors in the amp are combined (not sure of the term, but there are 2 caps in the cans). I'm assuming it's okay to replace these with singles, such as the sprague atoms. Also as for the others (blue ones in the pics), several sites have similar capacitance values, but higher voltages. Does the voltage make a difference as long as it is the minimum on the schematic?
I'm also going to replace the resistors on the power tubes as I read elsewhere that this was recommended.
Are there any recommendations on the caps, brand or otherwise? I've seen kits that have all the caps on the Kendrick site, but it looks like it would be cheaper to just order the stuff individually.
I'm also in need of a new speaker, since due to carelessness, I dropped the chassis, tearing out the speaker wires, managed to stop the chassis from hitting the floor though. I'm thinking Weber, but have not experience with these.
I've included pics of the chassis, it already has a 3-wire cord installed. Should I replace the cap under the ground switch, or does the new cord negate this?
Sorry for being long winded, but I'd like to get this right the first time, and would appreciate any input.

Thanks,
Ken

[jrfrond]

You can get ALL the parts you need for this, including the 25/25/25V dual caps and carbon comp resistors from Antique, though they are a bit pricey, and you CAN use single 22/25V axial caps and tie the negative sides together for common ground. I actually prefer this, because if one goes bad later, you only need to change a single, inexpensive cap.

Tube sockets, especially those sturdy old American ones used in that amp (usually either Cinch or Amphenol) are easily cleaned and retensioned. FIRST MAKE SURE YOU'VE DISCHARGED THE FILTER CAPS!!! Then, take a jeweler's screwdriver, a fine-point awl or something similar and insert it between the contact and tube socket body and force the contact spring together SLIGHTLY. It doesn't take much. Then, plug the tube in and out a couple of times when reinstalling to break up the oxide.

Please TRY TO RESIST using a residue-bearing contact cleaner or a tiny wire brush to clean the contacts. Any residue increases the chances of subsequent, latent contact carbonizing, and wirebrushing might remove what is left of the contact plating.

Usually, tube sockets can be fully rescued, but occasionally they require replacement. If you go this route, don't cheap out on these, and get ceramic replacements with gold-plated contact.

Oh yes, and cut that "Death Cap" the hell outta there!!! :O

[trem]

Wow!
What a nice, clean, original Fender. Just something to consider are the plate, grid, and screen resistors. I am painfully aware of how finicky the "collector value" of an amplifier can be. At some point (we all have to draw our own like) it just does not matter, unless the amp is a show piece and not a gigging instrument. I always change those afore mentioned resistors to 1 watt carbon film at the plates and other types at the grid and screens depending on the amp. The bias resistor is also a target for change. This can be a sore topic of debate however.
Although, I have had many experienced players plug into our amps with no complaint. Even though they are the owners of some very fine and original amps, nobody ever complained that our amps sounded flat. Nobody ever shook their head, commenting, "if it just didn't have those carbon film plate resistors". I realize that all components are "capable" of imparting some type of affect on tone. But I think the objection to change is often overstated, in knee jerk reflex.
That is a great amp you have there. I hope you enjoy it for many years to come.
Good Luck

[pdf64]

Great looking amp.
What rectifier tube is that? It looks bigger than a regular GZ34, maybe a 5U4. If so, it will reduce your power output, and make the power transformer run a little hotter, due to the 3 amp heater.
On the 4th pic, the pair of black wires from the power transformer look like the insulation has worn from rubbing on the underside of the cab. That could cause a horrible short eventually and really test that ground connection on the power cable. Best to check that out and maybe put some heat shrink sleeving over the worn section.
How about getting Weber, Orange County or someone to re-cone the speaker?
If you're replacing all the electrolytics, don't forget the bias cap on the small board by the power transformer. The original 50V spec was marginal, put a 70 or 100V replacement in.
To improve the functionality, consider the simple 1 wire mod to put reverb and trem onto both channels, which also gives you the option of using the non-bright normal channel with the reverb, which a lot of people like for overdrive pedals.
Peter.

[Dave Curtis, dB AudioTech]

"Please TRY TO RESIST using a residue-bearing contact cleaner or a tiny wire brush to clean the contacts. Any residue increases the chances of subsequent, latent contact carbonizing, and wirebrushing might remove what is left of the contact plating."


The only thing I use on tube pins/sockets (other than a non-residue cleaner and/or a burnisher) is Caig's GxL (ProGold). It's rated for the heat and works great! I've been using the pen-type applicator for years. It doesn't turn to varnish/carbon, and clears up "fizzy" sockets instantly.

I'll also advise the OP to rewire the AC switching; back then the fuse was put in the neutral line. It should be in the hot line: fuse, switch, tranny. The neutral should go directly to the other leg of the tranny primary. The now-defunct (and disconnected) polarity switch can be used to open the NFB loop for a bit more grind. Also, a great many Fenders had the AC convenience receptacle wired backwards. Check to make sure that the hot (black) wire goes to the terminal with the narrow slot (may or may not have a brass screw).

[melvin]

First stupid question, ProGold in a pen applicator? I've gotta get one of those...

Second, why do you rewire the fuse to the hot side? I was under the impression either side would work as well as the other...

Third, what if say, the club you are playing has a bad ground. Wouldn't the 'death cap' start working again? (And do you call it the 'death cap' because it can put the mains ac on the chassis?)

Of course, it wouldn't be a great reason to keep it.

And finally, what kind of safety checks do you do when finishing a repair?

[Dave Curtis, dB AudioTech]

First stupid question, ProGold in a pen applicator? I've gotta get one of those...

The last time I was in Radio Shack, I noticed they are stocking Caig products. I'm not sure if they had a ProGold pen, though. Most often, I'll just "paint" the tube pins with the stuff and work it in & out of the socket a few times; you don't need much. Very rarely the socket actually needs cleaning first (alcohol or non-residue contact cleaner & fine pipe cleaners). I got my pen about 5 years ago (about $25); every tube amp I've done gets treated, and occasionally that's fixed the problem. I also have a D5 pen that's relegated to non-heat apps; connectors, etc.

Second, why do you rewire the fuse to the hot side? I was under the impression either side would work as well as the other...

I do it to bring the amp up to current code standards. Fusing the neutral is very much a no-no nowadays, as there are certain fault conditions that won't blow the fuse and put the user or the equipment at risk (if the fuse does blow, the entire primary winding is still hot all the way to the fuseholder). The only time you're allowed to open the neutral is when the hot is opened at the same time, as in a 2 pole switch.

Third, what if say, the club you are playing has a bad ground. Wouldn't the 'death cap' start working again? (And do you call it the 'death cap' because it can put the mains ac on the chassis?)

Of course, it wouldn't be a great reason to keep it.

If that cap is leaky or shorted, you might never work again. You can replace it with an approved "safety" cap; these are made to fail in a safe manner if they do. Check out my "death cap commits suicide" thread.

And finally, what kind of safety checks do you do when finishing a repair?

The first safety check happens when I plug an amp into my bench power. More than once, a bad "polarity" cap has tripped my GFCI. They're designed to trip at about 5mA. A non-contact voltage tester is used to check the chassis for voltage; that's something I do at gigs, too. I'll also check receptacles at gigs with a plug-in tester; safety first!

DC
Master Electrician

"Being a conductor of an orchestra is good; being a conductor of electricity isnt!"